1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Kernel-based Virtual Machine driver for Linux
4 *
5 * AMD SVM-SEV support
6 *
7 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
8 */
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11 #include <linux/kvm_types.h>
12 #include <linux/kvm_host.h>
13 #include <linux/kernel.h>
14 #include <linux/highmem.h>
15 #include <linux/psp.h>
16 #include <linux/psp-sev.h>
17 #include <linux/pagemap.h>
18 #include <linux/swap.h>
19 #include <linux/misc_cgroup.h>
20 #include <linux/processor.h>
21 #include <linux/trace_events.h>
22
23 #include <asm/pkru.h>
24 #include <asm/trapnr.h>
25 #include <asm/fpu/xcr.h>
26 #include <asm/debugreg.h>
27
28 #include "mmu.h"
29 #include "x86.h"
30 #include "svm.h"
31 #include "svm_ops.h"
32 #include "cpuid.h"
33 #include "trace.h"
34
35 #ifndef CONFIG_KVM_AMD_SEV
36 /*
37 * When this config is not defined, SEV feature is not supported and APIs in
38 * this file are not used but this file still gets compiled into the KVM AMD
39 * module.
40 *
41 * We will not have MISC_CG_RES_SEV and MISC_CG_RES_SEV_ES entries in the enum
42 * misc_res_type {} defined in linux/misc_cgroup.h.
43 *
44 * Below macros allow compilation to succeed.
45 */
46 #define MISC_CG_RES_SEV MISC_CG_RES_TYPES
47 #define MISC_CG_RES_SEV_ES MISC_CG_RES_TYPES
48 #endif
49
50 #ifdef CONFIG_KVM_AMD_SEV
51 /* enable/disable SEV support */
52 static bool sev_enabled = true;
53 module_param_named(sev, sev_enabled, bool, 0444);
54
55 /* enable/disable SEV-ES support */
56 static bool sev_es_enabled = true;
57 module_param_named(sev_es, sev_es_enabled, bool, 0444);
58
59 /* enable/disable SEV-ES DebugSwap support */
60 static bool sev_es_debug_swap_enabled = false;
61 module_param_named(debug_swap, sev_es_debug_swap_enabled, bool, 0444);
62 #else
63 #define sev_enabled false
64 #define sev_es_enabled false
65 #define sev_es_debug_swap_enabled false
66 #endif /* CONFIG_KVM_AMD_SEV */
67
68 static u8 sev_enc_bit;
69 static DECLARE_RWSEM(sev_deactivate_lock);
70 static DEFINE_MUTEX(sev_bitmap_lock);
71 unsigned int max_sev_asid;
72 static unsigned int min_sev_asid;
73 static unsigned long sev_me_mask;
74 static unsigned int nr_asids;
75 static unsigned long *sev_asid_bitmap;
76 static unsigned long *sev_reclaim_asid_bitmap;
77
78 struct enc_region {
79 struct list_head list;
80 unsigned long npages;
81 struct page **pages;
82 unsigned long uaddr;
83 unsigned long size;
84 };
85
86 /* Called with the sev_bitmap_lock held, or on shutdown */
sev_flush_asids(int min_asid,int max_asid)87 static int sev_flush_asids(int min_asid, int max_asid)
88 {
89 int ret, asid, error = 0;
90
91 /* Check if there are any ASIDs to reclaim before performing a flush */
92 asid = find_next_bit(sev_reclaim_asid_bitmap, nr_asids, min_asid);
93 if (asid > max_asid)
94 return -EBUSY;
95
96 /*
97 * DEACTIVATE will clear the WBINVD indicator causing DF_FLUSH to fail,
98 * so it must be guarded.
99 */
100 down_write(&sev_deactivate_lock);
101
102 wbinvd_on_all_cpus();
103 ret = sev_guest_df_flush(&error);
104
105 up_write(&sev_deactivate_lock);
106
107 if (ret)
108 pr_err("SEV: DF_FLUSH failed, ret=%d, error=%#x\n", ret, error);
109
110 return ret;
111 }
112
is_mirroring_enc_context(struct kvm * kvm)113 static inline bool is_mirroring_enc_context(struct kvm *kvm)
114 {
115 return !!to_kvm_svm(kvm)->sev_info.enc_context_owner;
116 }
117
118 /* Must be called with the sev_bitmap_lock held */
__sev_recycle_asids(int min_asid,int max_asid)119 static bool __sev_recycle_asids(int min_asid, int max_asid)
120 {
121 if (sev_flush_asids(min_asid, max_asid))
122 return false;
123
124 /* The flush process will flush all reclaimable SEV and SEV-ES ASIDs */
125 bitmap_xor(sev_asid_bitmap, sev_asid_bitmap, sev_reclaim_asid_bitmap,
126 nr_asids);
127 bitmap_zero(sev_reclaim_asid_bitmap, nr_asids);
128
129 return true;
130 }
131
sev_misc_cg_try_charge(struct kvm_sev_info * sev)132 static int sev_misc_cg_try_charge(struct kvm_sev_info *sev)
133 {
134 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV;
135 return misc_cg_try_charge(type, sev->misc_cg, 1);
136 }
137
sev_misc_cg_uncharge(struct kvm_sev_info * sev)138 static void sev_misc_cg_uncharge(struct kvm_sev_info *sev)
139 {
140 enum misc_res_type type = sev->es_active ? MISC_CG_RES_SEV_ES : MISC_CG_RES_SEV;
141 misc_cg_uncharge(type, sev->misc_cg, 1);
142 }
143
sev_asid_new(struct kvm_sev_info * sev)144 static int sev_asid_new(struct kvm_sev_info *sev)
145 {
146 int asid, min_asid, max_asid, ret;
147 bool retry = true;
148
149 WARN_ON(sev->misc_cg);
150 sev->misc_cg = get_current_misc_cg();
151 ret = sev_misc_cg_try_charge(sev);
152 if (ret) {
153 put_misc_cg(sev->misc_cg);
154 sev->misc_cg = NULL;
155 return ret;
156 }
157
158 mutex_lock(&sev_bitmap_lock);
159
160 /*
161 * SEV-enabled guests must use asid from min_sev_asid to max_sev_asid.
162 * SEV-ES-enabled guest can use from 1 to min_sev_asid - 1.
163 */
164 min_asid = sev->es_active ? 1 : min_sev_asid;
165 max_asid = sev->es_active ? min_sev_asid - 1 : max_sev_asid;
166 again:
167 asid = find_next_zero_bit(sev_asid_bitmap, max_asid + 1, min_asid);
168 if (asid > max_asid) {
169 if (retry && __sev_recycle_asids(min_asid, max_asid)) {
170 retry = false;
171 goto again;
172 }
173 mutex_unlock(&sev_bitmap_lock);
174 ret = -EBUSY;
175 goto e_uncharge;
176 }
177
178 __set_bit(asid, sev_asid_bitmap);
179
180 mutex_unlock(&sev_bitmap_lock);
181
182 return asid;
183 e_uncharge:
184 sev_misc_cg_uncharge(sev);
185 put_misc_cg(sev->misc_cg);
186 sev->misc_cg = NULL;
187 return ret;
188 }
189
sev_get_asid(struct kvm * kvm)190 static int sev_get_asid(struct kvm *kvm)
191 {
192 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
193
194 return sev->asid;
195 }
196
sev_asid_free(struct kvm_sev_info * sev)197 static void sev_asid_free(struct kvm_sev_info *sev)
198 {
199 struct svm_cpu_data *sd;
200 int cpu;
201
202 mutex_lock(&sev_bitmap_lock);
203
204 __set_bit(sev->asid, sev_reclaim_asid_bitmap);
205
206 for_each_possible_cpu(cpu) {
207 sd = per_cpu_ptr(&svm_data, cpu);
208 sd->sev_vmcbs[sev->asid] = NULL;
209 }
210
211 mutex_unlock(&sev_bitmap_lock);
212
213 sev_misc_cg_uncharge(sev);
214 put_misc_cg(sev->misc_cg);
215 sev->misc_cg = NULL;
216 }
217
sev_decommission(unsigned int handle)218 static void sev_decommission(unsigned int handle)
219 {
220 struct sev_data_decommission decommission;
221
222 if (!handle)
223 return;
224
225 decommission.handle = handle;
226 sev_guest_decommission(&decommission, NULL);
227 }
228
sev_unbind_asid(struct kvm * kvm,unsigned int handle)229 static void sev_unbind_asid(struct kvm *kvm, unsigned int handle)
230 {
231 struct sev_data_deactivate deactivate;
232
233 if (!handle)
234 return;
235
236 deactivate.handle = handle;
237
238 /* Guard DEACTIVATE against WBINVD/DF_FLUSH used in ASID recycling */
239 down_read(&sev_deactivate_lock);
240 sev_guest_deactivate(&deactivate, NULL);
241 up_read(&sev_deactivate_lock);
242
243 sev_decommission(handle);
244 }
245
sev_guest_init(struct kvm * kvm,struct kvm_sev_cmd * argp)246 static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp)
247 {
248 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
249 int asid, ret;
250
251 if (kvm->created_vcpus)
252 return -EINVAL;
253
254 ret = -EBUSY;
255 if (unlikely(sev->active))
256 return ret;
257
258 sev->active = true;
259 sev->es_active = argp->id == KVM_SEV_ES_INIT;
260 asid = sev_asid_new(sev);
261 if (asid < 0)
262 goto e_no_asid;
263 sev->asid = asid;
264
265 ret = sev_platform_init(&argp->error);
266 if (ret)
267 goto e_free;
268
269 INIT_LIST_HEAD(&sev->regions_list);
270 INIT_LIST_HEAD(&sev->mirror_vms);
271
272 kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_SEV);
273
274 return 0;
275
276 e_free:
277 sev_asid_free(sev);
278 sev->asid = 0;
279 e_no_asid:
280 sev->es_active = false;
281 sev->active = false;
282 return ret;
283 }
284
sev_bind_asid(struct kvm * kvm,unsigned int handle,int * error)285 static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error)
286 {
287 struct sev_data_activate activate;
288 int asid = sev_get_asid(kvm);
289 int ret;
290
291 /* activate ASID on the given handle */
292 activate.handle = handle;
293 activate.asid = asid;
294 ret = sev_guest_activate(&activate, error);
295
296 return ret;
297 }
298
__sev_issue_cmd(int fd,int id,void * data,int * error)299 static int __sev_issue_cmd(int fd, int id, void *data, int *error)
300 {
301 struct fd f;
302 int ret;
303
304 f = fdget(fd);
305 if (!f.file)
306 return -EBADF;
307
308 ret = sev_issue_cmd_external_user(f.file, id, data, error);
309
310 fdput(f);
311 return ret;
312 }
313
sev_issue_cmd(struct kvm * kvm,int id,void * data,int * error)314 static int sev_issue_cmd(struct kvm *kvm, int id, void *data, int *error)
315 {
316 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
317
318 return __sev_issue_cmd(sev->fd, id, data, error);
319 }
320
sev_launch_start(struct kvm * kvm,struct kvm_sev_cmd * argp)321 static int sev_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp)
322 {
323 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
324 struct sev_data_launch_start start;
325 struct kvm_sev_launch_start params;
326 void *dh_blob, *session_blob;
327 int *error = &argp->error;
328 int ret;
329
330 if (!sev_guest(kvm))
331 return -ENOTTY;
332
333 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params)))
334 return -EFAULT;
335
336 memset(&start, 0, sizeof(start));
337
338 dh_blob = NULL;
339 if (params.dh_uaddr) {
340 dh_blob = psp_copy_user_blob(params.dh_uaddr, params.dh_len);
341 if (IS_ERR(dh_blob))
342 return PTR_ERR(dh_blob);
343
344 start.dh_cert_address = __sme_set(__pa(dh_blob));
345 start.dh_cert_len = params.dh_len;
346 }
347
348 session_blob = NULL;
349 if (params.session_uaddr) {
350 session_blob = psp_copy_user_blob(params.session_uaddr, params.session_len);
351 if (IS_ERR(session_blob)) {
352 ret = PTR_ERR(session_blob);
353 goto e_free_dh;
354 }
355
356 start.session_address = __sme_set(__pa(session_blob));
357 start.session_len = params.session_len;
358 }
359
360 start.handle = params.handle;
361 start.policy = params.policy;
362
363 /* create memory encryption context */
364 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_LAUNCH_START, &start, error);
365 if (ret)
366 goto e_free_session;
367
368 /* Bind ASID to this guest */
369 ret = sev_bind_asid(kvm, start.handle, error);
370 if (ret) {
371 sev_decommission(start.handle);
372 goto e_free_session;
373 }
374
375 /* return handle to userspace */
376 params.handle = start.handle;
377 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params))) {
378 sev_unbind_asid(kvm, start.handle);
379 ret = -EFAULT;
380 goto e_free_session;
381 }
382
383 sev->handle = start.handle;
384 sev->fd = argp->sev_fd;
385
386 e_free_session:
387 kfree(session_blob);
388 e_free_dh:
389 kfree(dh_blob);
390 return ret;
391 }
392
sev_pin_memory(struct kvm * kvm,unsigned long uaddr,unsigned long ulen,unsigned long * n,int write)393 static struct page **sev_pin_memory(struct kvm *kvm, unsigned long uaddr,
394 unsigned long ulen, unsigned long *n,
395 int write)
396 {
397 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
398 unsigned long npages, size;
399 int npinned;
400 unsigned long locked, lock_limit;
401 struct page **pages;
402 unsigned long first, last;
403 int ret;
404
405 lockdep_assert_held(&kvm->lock);
406
407 if (ulen == 0 || uaddr + ulen < uaddr)
408 return ERR_PTR(-EINVAL);
409
410 /* Calculate number of pages. */
411 first = (uaddr & PAGE_MASK) >> PAGE_SHIFT;
412 last = ((uaddr + ulen - 1) & PAGE_MASK) >> PAGE_SHIFT;
413 npages = (last - first + 1);
414
415 locked = sev->pages_locked + npages;
416 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
417 if (locked > lock_limit && !capable(CAP_IPC_LOCK)) {
418 pr_err("SEV: %lu locked pages exceed the lock limit of %lu.\n", locked, lock_limit);
419 return ERR_PTR(-ENOMEM);
420 }
421
422 if (WARN_ON_ONCE(npages > INT_MAX))
423 return ERR_PTR(-EINVAL);
424
425 /* Avoid using vmalloc for smaller buffers. */
426 size = npages * sizeof(struct page *);
427 if (size > PAGE_SIZE)
428 pages = __vmalloc(size, GFP_KERNEL_ACCOUNT | __GFP_ZERO);
429 else
430 pages = kmalloc(size, GFP_KERNEL_ACCOUNT);
431
432 if (!pages)
433 return ERR_PTR(-ENOMEM);
434
435 /* Pin the user virtual address. */
436 npinned = pin_user_pages_fast(uaddr, npages, write ? FOLL_WRITE : 0, pages);
437 if (npinned != npages) {
438 pr_err("SEV: Failure locking %lu pages.\n", npages);
439 ret = -ENOMEM;
440 goto err;
441 }
442
443 *n = npages;
444 sev->pages_locked = locked;
445
446 return pages;
447
448 err:
449 if (npinned > 0)
450 unpin_user_pages(pages, npinned);
451
452 kvfree(pages);
453 return ERR_PTR(ret);
454 }
455
sev_unpin_memory(struct kvm * kvm,struct page ** pages,unsigned long npages)456 static void sev_unpin_memory(struct kvm *kvm, struct page **pages,
457 unsigned long npages)
458 {
459 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
460
461 unpin_user_pages(pages, npages);
462 kvfree(pages);
463 sev->pages_locked -= npages;
464 }
465
sev_clflush_pages(struct page * pages[],unsigned long npages)466 static void sev_clflush_pages(struct page *pages[], unsigned long npages)
467 {
468 uint8_t *page_virtual;
469 unsigned long i;
470
471 if (this_cpu_has(X86_FEATURE_SME_COHERENT) || npages == 0 ||
472 pages == NULL)
473 return;
474
475 for (i = 0; i < npages; i++) {
476 page_virtual = kmap_local_page(pages[i]);
477 clflush_cache_range(page_virtual, PAGE_SIZE);
478 kunmap_local(page_virtual);
479 cond_resched();
480 }
481 }
482
get_num_contig_pages(unsigned long idx,struct page ** inpages,unsigned long npages)483 static unsigned long get_num_contig_pages(unsigned long idx,
484 struct page **inpages, unsigned long npages)
485 {
486 unsigned long paddr, next_paddr;
487 unsigned long i = idx + 1, pages = 1;
488
489 /* find the number of contiguous pages starting from idx */
490 paddr = __sme_page_pa(inpages[idx]);
491 while (i < npages) {
492 next_paddr = __sme_page_pa(inpages[i++]);
493 if ((paddr + PAGE_SIZE) == next_paddr) {
494 pages++;
495 paddr = next_paddr;
496 continue;
497 }
498 break;
499 }
500
501 return pages;
502 }
503
sev_launch_update_data(struct kvm * kvm,struct kvm_sev_cmd * argp)504 static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp)
505 {
506 unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i;
507 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
508 struct kvm_sev_launch_update_data params;
509 struct sev_data_launch_update_data data;
510 struct page **inpages;
511 int ret;
512
513 if (!sev_guest(kvm))
514 return -ENOTTY;
515
516 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params)))
517 return -EFAULT;
518
519 vaddr = params.uaddr;
520 size = params.len;
521 vaddr_end = vaddr + size;
522
523 /* Lock the user memory. */
524 inpages = sev_pin_memory(kvm, vaddr, size, &npages, 1);
525 if (IS_ERR(inpages))
526 return PTR_ERR(inpages);
527
528 /*
529 * Flush (on non-coherent CPUs) before LAUNCH_UPDATE encrypts pages in
530 * place; the cache may contain the data that was written unencrypted.
531 */
532 sev_clflush_pages(inpages, npages);
533
534 data.reserved = 0;
535 data.handle = sev->handle;
536
537 for (i = 0; vaddr < vaddr_end; vaddr = next_vaddr, i += pages) {
538 int offset, len;
539
540 /*
541 * If the user buffer is not page-aligned, calculate the offset
542 * within the page.
543 */
544 offset = vaddr & (PAGE_SIZE - 1);
545
546 /* Calculate the number of pages that can be encrypted in one go. */
547 pages = get_num_contig_pages(i, inpages, npages);
548
549 len = min_t(size_t, ((pages * PAGE_SIZE) - offset), size);
550
551 data.len = len;
552 data.address = __sme_page_pa(inpages[i]) + offset;
553 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_DATA, &data, &argp->error);
554 if (ret)
555 goto e_unpin;
556
557 size -= len;
558 next_vaddr = vaddr + len;
559 }
560
561 e_unpin:
562 /* content of memory is updated, mark pages dirty */
563 for (i = 0; i < npages; i++) {
564 set_page_dirty_lock(inpages[i]);
565 mark_page_accessed(inpages[i]);
566 }
567 /* unlock the user pages */
568 sev_unpin_memory(kvm, inpages, npages);
569 return ret;
570 }
571
sev_es_sync_vmsa(struct vcpu_svm * svm)572 static int sev_es_sync_vmsa(struct vcpu_svm *svm)
573 {
574 struct sev_es_save_area *save = svm->sev_es.vmsa;
575
576 /* Check some debug related fields before encrypting the VMSA */
577 if (svm->vcpu.guest_debug || (svm->vmcb->save.dr7 & ~DR7_FIXED_1))
578 return -EINVAL;
579
580 /*
581 * SEV-ES will use a VMSA that is pointed to by the VMCB, not
582 * the traditional VMSA that is part of the VMCB. Copy the
583 * traditional VMSA as it has been built so far (in prep
584 * for LAUNCH_UPDATE_VMSA) to be the initial SEV-ES state.
585 */
586 memcpy(save, &svm->vmcb->save, sizeof(svm->vmcb->save));
587
588 /* Sync registgers */
589 save->rax = svm->vcpu.arch.regs[VCPU_REGS_RAX];
590 save->rbx = svm->vcpu.arch.regs[VCPU_REGS_RBX];
591 save->rcx = svm->vcpu.arch.regs[VCPU_REGS_RCX];
592 save->rdx = svm->vcpu.arch.regs[VCPU_REGS_RDX];
593 save->rsp = svm->vcpu.arch.regs[VCPU_REGS_RSP];
594 save->rbp = svm->vcpu.arch.regs[VCPU_REGS_RBP];
595 save->rsi = svm->vcpu.arch.regs[VCPU_REGS_RSI];
596 save->rdi = svm->vcpu.arch.regs[VCPU_REGS_RDI];
597 #ifdef CONFIG_X86_64
598 save->r8 = svm->vcpu.arch.regs[VCPU_REGS_R8];
599 save->r9 = svm->vcpu.arch.regs[VCPU_REGS_R9];
600 save->r10 = svm->vcpu.arch.regs[VCPU_REGS_R10];
601 save->r11 = svm->vcpu.arch.regs[VCPU_REGS_R11];
602 save->r12 = svm->vcpu.arch.regs[VCPU_REGS_R12];
603 save->r13 = svm->vcpu.arch.regs[VCPU_REGS_R13];
604 save->r14 = svm->vcpu.arch.regs[VCPU_REGS_R14];
605 save->r15 = svm->vcpu.arch.regs[VCPU_REGS_R15];
606 #endif
607 save->rip = svm->vcpu.arch.regs[VCPU_REGS_RIP];
608
609 /* Sync some non-GPR registers before encrypting */
610 save->xcr0 = svm->vcpu.arch.xcr0;
611 save->pkru = svm->vcpu.arch.pkru;
612 save->xss = svm->vcpu.arch.ia32_xss;
613 save->dr6 = svm->vcpu.arch.dr6;
614
615 if (sev_es_debug_swap_enabled) {
616 save->sev_features |= SVM_SEV_FEAT_DEBUG_SWAP;
617 pr_warn_once("Enabling DebugSwap with KVM_SEV_ES_INIT. "
618 "This will not work starting with Linux 6.10\n");
619 }
620
621 pr_debug("Virtual Machine Save Area (VMSA):\n");
622 print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, save, sizeof(*save), false);
623
624 return 0;
625 }
626
__sev_launch_update_vmsa(struct kvm * kvm,struct kvm_vcpu * vcpu,int * error)627 static int __sev_launch_update_vmsa(struct kvm *kvm, struct kvm_vcpu *vcpu,
628 int *error)
629 {
630 struct sev_data_launch_update_vmsa vmsa;
631 struct vcpu_svm *svm = to_svm(vcpu);
632 int ret;
633
634 if (vcpu->guest_debug) {
635 pr_warn_once("KVM_SET_GUEST_DEBUG for SEV-ES guest is not supported");
636 return -EINVAL;
637 }
638
639 /* Perform some pre-encryption checks against the VMSA */
640 ret = sev_es_sync_vmsa(svm);
641 if (ret)
642 return ret;
643
644 /*
645 * The LAUNCH_UPDATE_VMSA command will perform in-place encryption of
646 * the VMSA memory content (i.e it will write the same memory region
647 * with the guest's key), so invalidate it first.
648 */
649 clflush_cache_range(svm->sev_es.vmsa, PAGE_SIZE);
650
651 vmsa.reserved = 0;
652 vmsa.handle = to_kvm_svm(kvm)->sev_info.handle;
653 vmsa.address = __sme_pa(svm->sev_es.vmsa);
654 vmsa.len = PAGE_SIZE;
655 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_VMSA, &vmsa, error);
656 if (ret)
657 return ret;
658
659 vcpu->arch.guest_state_protected = true;
660 return 0;
661 }
662
sev_launch_update_vmsa(struct kvm * kvm,struct kvm_sev_cmd * argp)663 static int sev_launch_update_vmsa(struct kvm *kvm, struct kvm_sev_cmd *argp)
664 {
665 struct kvm_vcpu *vcpu;
666 unsigned long i;
667 int ret;
668
669 if (!sev_es_guest(kvm))
670 return -ENOTTY;
671
672 kvm_for_each_vcpu(i, vcpu, kvm) {
673 ret = mutex_lock_killable(&vcpu->mutex);
674 if (ret)
675 return ret;
676
677 ret = __sev_launch_update_vmsa(kvm, vcpu, &argp->error);
678
679 mutex_unlock(&vcpu->mutex);
680 if (ret)
681 return ret;
682 }
683
684 return 0;
685 }
686
sev_launch_measure(struct kvm * kvm,struct kvm_sev_cmd * argp)687 static int sev_launch_measure(struct kvm *kvm, struct kvm_sev_cmd *argp)
688 {
689 void __user *measure = (void __user *)(uintptr_t)argp->data;
690 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
691 struct sev_data_launch_measure data;
692 struct kvm_sev_launch_measure params;
693 void __user *p = NULL;
694 void *blob = NULL;
695 int ret;
696
697 if (!sev_guest(kvm))
698 return -ENOTTY;
699
700 if (copy_from_user(¶ms, measure, sizeof(params)))
701 return -EFAULT;
702
703 memset(&data, 0, sizeof(data));
704
705 /* User wants to query the blob length */
706 if (!params.len)
707 goto cmd;
708
709 p = (void __user *)(uintptr_t)params.uaddr;
710 if (p) {
711 if (params.len > SEV_FW_BLOB_MAX_SIZE)
712 return -EINVAL;
713
714 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT);
715 if (!blob)
716 return -ENOMEM;
717
718 data.address = __psp_pa(blob);
719 data.len = params.len;
720 }
721
722 cmd:
723 data.handle = sev->handle;
724 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_MEASURE, &data, &argp->error);
725
726 /*
727 * If we query the session length, FW responded with expected data.
728 */
729 if (!params.len)
730 goto done;
731
732 if (ret)
733 goto e_free_blob;
734
735 if (blob) {
736 if (copy_to_user(p, blob, params.len))
737 ret = -EFAULT;
738 }
739
740 done:
741 params.len = data.len;
742 if (copy_to_user(measure, ¶ms, sizeof(params)))
743 ret = -EFAULT;
744 e_free_blob:
745 kfree(blob);
746 return ret;
747 }
748
sev_launch_finish(struct kvm * kvm,struct kvm_sev_cmd * argp)749 static int sev_launch_finish(struct kvm *kvm, struct kvm_sev_cmd *argp)
750 {
751 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
752 struct sev_data_launch_finish data;
753
754 if (!sev_guest(kvm))
755 return -ENOTTY;
756
757 data.handle = sev->handle;
758 return sev_issue_cmd(kvm, SEV_CMD_LAUNCH_FINISH, &data, &argp->error);
759 }
760
sev_guest_status(struct kvm * kvm,struct kvm_sev_cmd * argp)761 static int sev_guest_status(struct kvm *kvm, struct kvm_sev_cmd *argp)
762 {
763 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
764 struct kvm_sev_guest_status params;
765 struct sev_data_guest_status data;
766 int ret;
767
768 if (!sev_guest(kvm))
769 return -ENOTTY;
770
771 memset(&data, 0, sizeof(data));
772
773 data.handle = sev->handle;
774 ret = sev_issue_cmd(kvm, SEV_CMD_GUEST_STATUS, &data, &argp->error);
775 if (ret)
776 return ret;
777
778 params.policy = data.policy;
779 params.state = data.state;
780 params.handle = data.handle;
781
782 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, sizeof(params)))
783 ret = -EFAULT;
784
785 return ret;
786 }
787
__sev_issue_dbg_cmd(struct kvm * kvm,unsigned long src,unsigned long dst,int size,int * error,bool enc)788 static int __sev_issue_dbg_cmd(struct kvm *kvm, unsigned long src,
789 unsigned long dst, int size,
790 int *error, bool enc)
791 {
792 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
793 struct sev_data_dbg data;
794
795 data.reserved = 0;
796 data.handle = sev->handle;
797 data.dst_addr = dst;
798 data.src_addr = src;
799 data.len = size;
800
801 return sev_issue_cmd(kvm,
802 enc ? SEV_CMD_DBG_ENCRYPT : SEV_CMD_DBG_DECRYPT,
803 &data, error);
804 }
805
__sev_dbg_decrypt(struct kvm * kvm,unsigned long src_paddr,unsigned long dst_paddr,int sz,int * err)806 static int __sev_dbg_decrypt(struct kvm *kvm, unsigned long src_paddr,
807 unsigned long dst_paddr, int sz, int *err)
808 {
809 int offset;
810
811 /*
812 * Its safe to read more than we are asked, caller should ensure that
813 * destination has enough space.
814 */
815 offset = src_paddr & 15;
816 src_paddr = round_down(src_paddr, 16);
817 sz = round_up(sz + offset, 16);
818
819 return __sev_issue_dbg_cmd(kvm, src_paddr, dst_paddr, sz, err, false);
820 }
821
__sev_dbg_decrypt_user(struct kvm * kvm,unsigned long paddr,void __user * dst_uaddr,unsigned long dst_paddr,int size,int * err)822 static int __sev_dbg_decrypt_user(struct kvm *kvm, unsigned long paddr,
823 void __user *dst_uaddr,
824 unsigned long dst_paddr,
825 int size, int *err)
826 {
827 struct page *tpage = NULL;
828 int ret, offset;
829
830 /* if inputs are not 16-byte then use intermediate buffer */
831 if (!IS_ALIGNED(dst_paddr, 16) ||
832 !IS_ALIGNED(paddr, 16) ||
833 !IS_ALIGNED(size, 16)) {
834 tpage = (void *)alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
835 if (!tpage)
836 return -ENOMEM;
837
838 dst_paddr = __sme_page_pa(tpage);
839 }
840
841 ret = __sev_dbg_decrypt(kvm, paddr, dst_paddr, size, err);
842 if (ret)
843 goto e_free;
844
845 if (tpage) {
846 offset = paddr & 15;
847 if (copy_to_user(dst_uaddr, page_address(tpage) + offset, size))
848 ret = -EFAULT;
849 }
850
851 e_free:
852 if (tpage)
853 __free_page(tpage);
854
855 return ret;
856 }
857
__sev_dbg_encrypt_user(struct kvm * kvm,unsigned long paddr,void __user * vaddr,unsigned long dst_paddr,void __user * dst_vaddr,int size,int * error)858 static int __sev_dbg_encrypt_user(struct kvm *kvm, unsigned long paddr,
859 void __user *vaddr,
860 unsigned long dst_paddr,
861 void __user *dst_vaddr,
862 int size, int *error)
863 {
864 struct page *src_tpage = NULL;
865 struct page *dst_tpage = NULL;
866 int ret, len = size;
867
868 /* If source buffer is not aligned then use an intermediate buffer */
869 if (!IS_ALIGNED((unsigned long)vaddr, 16)) {
870 src_tpage = alloc_page(GFP_KERNEL_ACCOUNT);
871 if (!src_tpage)
872 return -ENOMEM;
873
874 if (copy_from_user(page_address(src_tpage), vaddr, size)) {
875 __free_page(src_tpage);
876 return -EFAULT;
877 }
878
879 paddr = __sme_page_pa(src_tpage);
880 }
881
882 /*
883 * If destination buffer or length is not aligned then do read-modify-write:
884 * - decrypt destination in an intermediate buffer
885 * - copy the source buffer in an intermediate buffer
886 * - use the intermediate buffer as source buffer
887 */
888 if (!IS_ALIGNED((unsigned long)dst_vaddr, 16) || !IS_ALIGNED(size, 16)) {
889 int dst_offset;
890
891 dst_tpage = alloc_page(GFP_KERNEL_ACCOUNT);
892 if (!dst_tpage) {
893 ret = -ENOMEM;
894 goto e_free;
895 }
896
897 ret = __sev_dbg_decrypt(kvm, dst_paddr,
898 __sme_page_pa(dst_tpage), size, error);
899 if (ret)
900 goto e_free;
901
902 /*
903 * If source is kernel buffer then use memcpy() otherwise
904 * copy_from_user().
905 */
906 dst_offset = dst_paddr & 15;
907
908 if (src_tpage)
909 memcpy(page_address(dst_tpage) + dst_offset,
910 page_address(src_tpage), size);
911 else {
912 if (copy_from_user(page_address(dst_tpage) + dst_offset,
913 vaddr, size)) {
914 ret = -EFAULT;
915 goto e_free;
916 }
917 }
918
919 paddr = __sme_page_pa(dst_tpage);
920 dst_paddr = round_down(dst_paddr, 16);
921 len = round_up(size, 16);
922 }
923
924 ret = __sev_issue_dbg_cmd(kvm, paddr, dst_paddr, len, error, true);
925
926 e_free:
927 if (src_tpage)
928 __free_page(src_tpage);
929 if (dst_tpage)
930 __free_page(dst_tpage);
931 return ret;
932 }
933
sev_dbg_crypt(struct kvm * kvm,struct kvm_sev_cmd * argp,bool dec)934 static int sev_dbg_crypt(struct kvm *kvm, struct kvm_sev_cmd *argp, bool dec)
935 {
936 unsigned long vaddr, vaddr_end, next_vaddr;
937 unsigned long dst_vaddr;
938 struct page **src_p, **dst_p;
939 struct kvm_sev_dbg debug;
940 unsigned long n;
941 unsigned int size;
942 int ret;
943
944 if (!sev_guest(kvm))
945 return -ENOTTY;
946
947 if (copy_from_user(&debug, (void __user *)(uintptr_t)argp->data, sizeof(debug)))
948 return -EFAULT;
949
950 if (!debug.len || debug.src_uaddr + debug.len < debug.src_uaddr)
951 return -EINVAL;
952 if (!debug.dst_uaddr)
953 return -EINVAL;
954
955 vaddr = debug.src_uaddr;
956 size = debug.len;
957 vaddr_end = vaddr + size;
958 dst_vaddr = debug.dst_uaddr;
959
960 for (; vaddr < vaddr_end; vaddr = next_vaddr) {
961 int len, s_off, d_off;
962
963 /* lock userspace source and destination page */
964 src_p = sev_pin_memory(kvm, vaddr & PAGE_MASK, PAGE_SIZE, &n, 0);
965 if (IS_ERR(src_p))
966 return PTR_ERR(src_p);
967
968 dst_p = sev_pin_memory(kvm, dst_vaddr & PAGE_MASK, PAGE_SIZE, &n, 1);
969 if (IS_ERR(dst_p)) {
970 sev_unpin_memory(kvm, src_p, n);
971 return PTR_ERR(dst_p);
972 }
973
974 /*
975 * Flush (on non-coherent CPUs) before DBG_{DE,EN}CRYPT read or modify
976 * the pages; flush the destination too so that future accesses do not
977 * see stale data.
978 */
979 sev_clflush_pages(src_p, 1);
980 sev_clflush_pages(dst_p, 1);
981
982 /*
983 * Since user buffer may not be page aligned, calculate the
984 * offset within the page.
985 */
986 s_off = vaddr & ~PAGE_MASK;
987 d_off = dst_vaddr & ~PAGE_MASK;
988 len = min_t(size_t, (PAGE_SIZE - s_off), size);
989
990 if (dec)
991 ret = __sev_dbg_decrypt_user(kvm,
992 __sme_page_pa(src_p[0]) + s_off,
993 (void __user *)dst_vaddr,
994 __sme_page_pa(dst_p[0]) + d_off,
995 len, &argp->error);
996 else
997 ret = __sev_dbg_encrypt_user(kvm,
998 __sme_page_pa(src_p[0]) + s_off,
999 (void __user *)vaddr,
1000 __sme_page_pa(dst_p[0]) + d_off,
1001 (void __user *)dst_vaddr,
1002 len, &argp->error);
1003
1004 sev_unpin_memory(kvm, src_p, n);
1005 sev_unpin_memory(kvm, dst_p, n);
1006
1007 if (ret)
1008 goto err;
1009
1010 next_vaddr = vaddr + len;
1011 dst_vaddr = dst_vaddr + len;
1012 size -= len;
1013 }
1014 err:
1015 return ret;
1016 }
1017
sev_launch_secret(struct kvm * kvm,struct kvm_sev_cmd * argp)1018 static int sev_launch_secret(struct kvm *kvm, struct kvm_sev_cmd *argp)
1019 {
1020 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1021 struct sev_data_launch_secret data;
1022 struct kvm_sev_launch_secret params;
1023 struct page **pages;
1024 void *blob, *hdr;
1025 unsigned long n, i;
1026 int ret, offset;
1027
1028 if (!sev_guest(kvm))
1029 return -ENOTTY;
1030
1031 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params)))
1032 return -EFAULT;
1033
1034 pages = sev_pin_memory(kvm, params.guest_uaddr, params.guest_len, &n, 1);
1035 if (IS_ERR(pages))
1036 return PTR_ERR(pages);
1037
1038 /*
1039 * Flush (on non-coherent CPUs) before LAUNCH_SECRET encrypts pages in
1040 * place; the cache may contain the data that was written unencrypted.
1041 */
1042 sev_clflush_pages(pages, n);
1043
1044 /*
1045 * The secret must be copied into contiguous memory region, lets verify
1046 * that userspace memory pages are contiguous before we issue command.
1047 */
1048 if (get_num_contig_pages(0, pages, n) != n) {
1049 ret = -EINVAL;
1050 goto e_unpin_memory;
1051 }
1052
1053 memset(&data, 0, sizeof(data));
1054
1055 offset = params.guest_uaddr & (PAGE_SIZE - 1);
1056 data.guest_address = __sme_page_pa(pages[0]) + offset;
1057 data.guest_len = params.guest_len;
1058
1059 blob = psp_copy_user_blob(params.trans_uaddr, params.trans_len);
1060 if (IS_ERR(blob)) {
1061 ret = PTR_ERR(blob);
1062 goto e_unpin_memory;
1063 }
1064
1065 data.trans_address = __psp_pa(blob);
1066 data.trans_len = params.trans_len;
1067
1068 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len);
1069 if (IS_ERR(hdr)) {
1070 ret = PTR_ERR(hdr);
1071 goto e_free_blob;
1072 }
1073 data.hdr_address = __psp_pa(hdr);
1074 data.hdr_len = params.hdr_len;
1075
1076 data.handle = sev->handle;
1077 ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_SECRET, &data, &argp->error);
1078
1079 kfree(hdr);
1080
1081 e_free_blob:
1082 kfree(blob);
1083 e_unpin_memory:
1084 /* content of memory is updated, mark pages dirty */
1085 for (i = 0; i < n; i++) {
1086 set_page_dirty_lock(pages[i]);
1087 mark_page_accessed(pages[i]);
1088 }
1089 sev_unpin_memory(kvm, pages, n);
1090 return ret;
1091 }
1092
sev_get_attestation_report(struct kvm * kvm,struct kvm_sev_cmd * argp)1093 static int sev_get_attestation_report(struct kvm *kvm, struct kvm_sev_cmd *argp)
1094 {
1095 void __user *report = (void __user *)(uintptr_t)argp->data;
1096 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1097 struct sev_data_attestation_report data;
1098 struct kvm_sev_attestation_report params;
1099 void __user *p;
1100 void *blob = NULL;
1101 int ret;
1102
1103 if (!sev_guest(kvm))
1104 return -ENOTTY;
1105
1106 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params)))
1107 return -EFAULT;
1108
1109 memset(&data, 0, sizeof(data));
1110
1111 /* User wants to query the blob length */
1112 if (!params.len)
1113 goto cmd;
1114
1115 p = (void __user *)(uintptr_t)params.uaddr;
1116 if (p) {
1117 if (params.len > SEV_FW_BLOB_MAX_SIZE)
1118 return -EINVAL;
1119
1120 blob = kzalloc(params.len, GFP_KERNEL_ACCOUNT);
1121 if (!blob)
1122 return -ENOMEM;
1123
1124 data.address = __psp_pa(blob);
1125 data.len = params.len;
1126 memcpy(data.mnonce, params.mnonce, sizeof(params.mnonce));
1127 }
1128 cmd:
1129 data.handle = sev->handle;
1130 ret = sev_issue_cmd(kvm, SEV_CMD_ATTESTATION_REPORT, &data, &argp->error);
1131 /*
1132 * If we query the session length, FW responded with expected data.
1133 */
1134 if (!params.len)
1135 goto done;
1136
1137 if (ret)
1138 goto e_free_blob;
1139
1140 if (blob) {
1141 if (copy_to_user(p, blob, params.len))
1142 ret = -EFAULT;
1143 }
1144
1145 done:
1146 params.len = data.len;
1147 if (copy_to_user(report, ¶ms, sizeof(params)))
1148 ret = -EFAULT;
1149 e_free_blob:
1150 kfree(blob);
1151 return ret;
1152 }
1153
1154 /* Userspace wants to query session length. */
1155 static int
__sev_send_start_query_session_length(struct kvm * kvm,struct kvm_sev_cmd * argp,struct kvm_sev_send_start * params)1156 __sev_send_start_query_session_length(struct kvm *kvm, struct kvm_sev_cmd *argp,
1157 struct kvm_sev_send_start *params)
1158 {
1159 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1160 struct sev_data_send_start data;
1161 int ret;
1162
1163 memset(&data, 0, sizeof(data));
1164 data.handle = sev->handle;
1165 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error);
1166
1167 params->session_len = data.session_len;
1168 if (copy_to_user((void __user *)(uintptr_t)argp->data, params,
1169 sizeof(struct kvm_sev_send_start)))
1170 ret = -EFAULT;
1171
1172 return ret;
1173 }
1174
sev_send_start(struct kvm * kvm,struct kvm_sev_cmd * argp)1175 static int sev_send_start(struct kvm *kvm, struct kvm_sev_cmd *argp)
1176 {
1177 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1178 struct sev_data_send_start data;
1179 struct kvm_sev_send_start params;
1180 void *amd_certs, *session_data;
1181 void *pdh_cert, *plat_certs;
1182 int ret;
1183
1184 if (!sev_guest(kvm))
1185 return -ENOTTY;
1186
1187 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data,
1188 sizeof(struct kvm_sev_send_start)))
1189 return -EFAULT;
1190
1191 /* if session_len is zero, userspace wants to query the session length */
1192 if (!params.session_len)
1193 return __sev_send_start_query_session_length(kvm, argp,
1194 ¶ms);
1195
1196 /* some sanity checks */
1197 if (!params.pdh_cert_uaddr || !params.pdh_cert_len ||
1198 !params.session_uaddr || params.session_len > SEV_FW_BLOB_MAX_SIZE)
1199 return -EINVAL;
1200
1201 /* allocate the memory to hold the session data blob */
1202 session_data = kzalloc(params.session_len, GFP_KERNEL_ACCOUNT);
1203 if (!session_data)
1204 return -ENOMEM;
1205
1206 /* copy the certificate blobs from userspace */
1207 pdh_cert = psp_copy_user_blob(params.pdh_cert_uaddr,
1208 params.pdh_cert_len);
1209 if (IS_ERR(pdh_cert)) {
1210 ret = PTR_ERR(pdh_cert);
1211 goto e_free_session;
1212 }
1213
1214 plat_certs = psp_copy_user_blob(params.plat_certs_uaddr,
1215 params.plat_certs_len);
1216 if (IS_ERR(plat_certs)) {
1217 ret = PTR_ERR(plat_certs);
1218 goto e_free_pdh;
1219 }
1220
1221 amd_certs = psp_copy_user_blob(params.amd_certs_uaddr,
1222 params.amd_certs_len);
1223 if (IS_ERR(amd_certs)) {
1224 ret = PTR_ERR(amd_certs);
1225 goto e_free_plat_cert;
1226 }
1227
1228 /* populate the FW SEND_START field with system physical address */
1229 memset(&data, 0, sizeof(data));
1230 data.pdh_cert_address = __psp_pa(pdh_cert);
1231 data.pdh_cert_len = params.pdh_cert_len;
1232 data.plat_certs_address = __psp_pa(plat_certs);
1233 data.plat_certs_len = params.plat_certs_len;
1234 data.amd_certs_address = __psp_pa(amd_certs);
1235 data.amd_certs_len = params.amd_certs_len;
1236 data.session_address = __psp_pa(session_data);
1237 data.session_len = params.session_len;
1238 data.handle = sev->handle;
1239
1240 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_START, &data, &argp->error);
1241
1242 if (!ret && copy_to_user((void __user *)(uintptr_t)params.session_uaddr,
1243 session_data, params.session_len)) {
1244 ret = -EFAULT;
1245 goto e_free_amd_cert;
1246 }
1247
1248 params.policy = data.policy;
1249 params.session_len = data.session_len;
1250 if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms,
1251 sizeof(struct kvm_sev_send_start)))
1252 ret = -EFAULT;
1253
1254 e_free_amd_cert:
1255 kfree(amd_certs);
1256 e_free_plat_cert:
1257 kfree(plat_certs);
1258 e_free_pdh:
1259 kfree(pdh_cert);
1260 e_free_session:
1261 kfree(session_data);
1262 return ret;
1263 }
1264
1265 /* Userspace wants to query either header or trans length. */
1266 static int
__sev_send_update_data_query_lengths(struct kvm * kvm,struct kvm_sev_cmd * argp,struct kvm_sev_send_update_data * params)1267 __sev_send_update_data_query_lengths(struct kvm *kvm, struct kvm_sev_cmd *argp,
1268 struct kvm_sev_send_update_data *params)
1269 {
1270 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1271 struct sev_data_send_update_data data;
1272 int ret;
1273
1274 memset(&data, 0, sizeof(data));
1275 data.handle = sev->handle;
1276 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error);
1277
1278 params->hdr_len = data.hdr_len;
1279 params->trans_len = data.trans_len;
1280
1281 if (copy_to_user((void __user *)(uintptr_t)argp->data, params,
1282 sizeof(struct kvm_sev_send_update_data)))
1283 ret = -EFAULT;
1284
1285 return ret;
1286 }
1287
sev_send_update_data(struct kvm * kvm,struct kvm_sev_cmd * argp)1288 static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp)
1289 {
1290 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1291 struct sev_data_send_update_data data;
1292 struct kvm_sev_send_update_data params;
1293 void *hdr, *trans_data;
1294 struct page **guest_page;
1295 unsigned long n;
1296 int ret, offset;
1297
1298 if (!sev_guest(kvm))
1299 return -ENOTTY;
1300
1301 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data,
1302 sizeof(struct kvm_sev_send_update_data)))
1303 return -EFAULT;
1304
1305 /* userspace wants to query either header or trans length */
1306 if (!params.trans_len || !params.hdr_len)
1307 return __sev_send_update_data_query_lengths(kvm, argp, ¶ms);
1308
1309 if (!params.trans_uaddr || !params.guest_uaddr ||
1310 !params.guest_len || !params.hdr_uaddr)
1311 return -EINVAL;
1312
1313 /* Check if we are crossing the page boundary */
1314 offset = params.guest_uaddr & (PAGE_SIZE - 1);
1315 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE)
1316 return -EINVAL;
1317
1318 /* Pin guest memory */
1319 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK,
1320 PAGE_SIZE, &n, 0);
1321 if (IS_ERR(guest_page))
1322 return PTR_ERR(guest_page);
1323
1324 /* allocate memory for header and transport buffer */
1325 ret = -ENOMEM;
1326 hdr = kzalloc(params.hdr_len, GFP_KERNEL_ACCOUNT);
1327 if (!hdr)
1328 goto e_unpin;
1329
1330 trans_data = kzalloc(params.trans_len, GFP_KERNEL_ACCOUNT);
1331 if (!trans_data)
1332 goto e_free_hdr;
1333
1334 memset(&data, 0, sizeof(data));
1335 data.hdr_address = __psp_pa(hdr);
1336 data.hdr_len = params.hdr_len;
1337 data.trans_address = __psp_pa(trans_data);
1338 data.trans_len = params.trans_len;
1339
1340 /* The SEND_UPDATE_DATA command requires C-bit to be always set. */
1341 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset;
1342 data.guest_address |= sev_me_mask;
1343 data.guest_len = params.guest_len;
1344 data.handle = sev->handle;
1345
1346 ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, &data, &argp->error);
1347
1348 if (ret)
1349 goto e_free_trans_data;
1350
1351 /* copy transport buffer to user space */
1352 if (copy_to_user((void __user *)(uintptr_t)params.trans_uaddr,
1353 trans_data, params.trans_len)) {
1354 ret = -EFAULT;
1355 goto e_free_trans_data;
1356 }
1357
1358 /* Copy packet header to userspace. */
1359 if (copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, hdr,
1360 params.hdr_len))
1361 ret = -EFAULT;
1362
1363 e_free_trans_data:
1364 kfree(trans_data);
1365 e_free_hdr:
1366 kfree(hdr);
1367 e_unpin:
1368 sev_unpin_memory(kvm, guest_page, n);
1369
1370 return ret;
1371 }
1372
sev_send_finish(struct kvm * kvm,struct kvm_sev_cmd * argp)1373 static int sev_send_finish(struct kvm *kvm, struct kvm_sev_cmd *argp)
1374 {
1375 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1376 struct sev_data_send_finish data;
1377
1378 if (!sev_guest(kvm))
1379 return -ENOTTY;
1380
1381 data.handle = sev->handle;
1382 return sev_issue_cmd(kvm, SEV_CMD_SEND_FINISH, &data, &argp->error);
1383 }
1384
sev_send_cancel(struct kvm * kvm,struct kvm_sev_cmd * argp)1385 static int sev_send_cancel(struct kvm *kvm, struct kvm_sev_cmd *argp)
1386 {
1387 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1388 struct sev_data_send_cancel data;
1389
1390 if (!sev_guest(kvm))
1391 return -ENOTTY;
1392
1393 data.handle = sev->handle;
1394 return sev_issue_cmd(kvm, SEV_CMD_SEND_CANCEL, &data, &argp->error);
1395 }
1396
sev_receive_start(struct kvm * kvm,struct kvm_sev_cmd * argp)1397 static int sev_receive_start(struct kvm *kvm, struct kvm_sev_cmd *argp)
1398 {
1399 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1400 struct sev_data_receive_start start;
1401 struct kvm_sev_receive_start params;
1402 int *error = &argp->error;
1403 void *session_data;
1404 void *pdh_data;
1405 int ret;
1406
1407 if (!sev_guest(kvm))
1408 return -ENOTTY;
1409
1410 /* Get parameter from the userspace */
1411 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data,
1412 sizeof(struct kvm_sev_receive_start)))
1413 return -EFAULT;
1414
1415 /* some sanity checks */
1416 if (!params.pdh_uaddr || !params.pdh_len ||
1417 !params.session_uaddr || !params.session_len)
1418 return -EINVAL;
1419
1420 pdh_data = psp_copy_user_blob(params.pdh_uaddr, params.pdh_len);
1421 if (IS_ERR(pdh_data))
1422 return PTR_ERR(pdh_data);
1423
1424 session_data = psp_copy_user_blob(params.session_uaddr,
1425 params.session_len);
1426 if (IS_ERR(session_data)) {
1427 ret = PTR_ERR(session_data);
1428 goto e_free_pdh;
1429 }
1430
1431 memset(&start, 0, sizeof(start));
1432 start.handle = params.handle;
1433 start.policy = params.policy;
1434 start.pdh_cert_address = __psp_pa(pdh_data);
1435 start.pdh_cert_len = params.pdh_len;
1436 start.session_address = __psp_pa(session_data);
1437 start.session_len = params.session_len;
1438
1439 /* create memory encryption context */
1440 ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_RECEIVE_START, &start,
1441 error);
1442 if (ret)
1443 goto e_free_session;
1444
1445 /* Bind ASID to this guest */
1446 ret = sev_bind_asid(kvm, start.handle, error);
1447 if (ret) {
1448 sev_decommission(start.handle);
1449 goto e_free_session;
1450 }
1451
1452 params.handle = start.handle;
1453 if (copy_to_user((void __user *)(uintptr_t)argp->data,
1454 ¶ms, sizeof(struct kvm_sev_receive_start))) {
1455 ret = -EFAULT;
1456 sev_unbind_asid(kvm, start.handle);
1457 goto e_free_session;
1458 }
1459
1460 sev->handle = start.handle;
1461 sev->fd = argp->sev_fd;
1462
1463 e_free_session:
1464 kfree(session_data);
1465 e_free_pdh:
1466 kfree(pdh_data);
1467
1468 return ret;
1469 }
1470
sev_receive_update_data(struct kvm * kvm,struct kvm_sev_cmd * argp)1471 static int sev_receive_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp)
1472 {
1473 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1474 struct kvm_sev_receive_update_data params;
1475 struct sev_data_receive_update_data data;
1476 void *hdr = NULL, *trans = NULL;
1477 struct page **guest_page;
1478 unsigned long n;
1479 int ret, offset;
1480
1481 if (!sev_guest(kvm))
1482 return -EINVAL;
1483
1484 if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data,
1485 sizeof(struct kvm_sev_receive_update_data)))
1486 return -EFAULT;
1487
1488 if (!params.hdr_uaddr || !params.hdr_len ||
1489 !params.guest_uaddr || !params.guest_len ||
1490 !params.trans_uaddr || !params.trans_len)
1491 return -EINVAL;
1492
1493 /* Check if we are crossing the page boundary */
1494 offset = params.guest_uaddr & (PAGE_SIZE - 1);
1495 if (params.guest_len > PAGE_SIZE || (params.guest_len + offset) > PAGE_SIZE)
1496 return -EINVAL;
1497
1498 hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len);
1499 if (IS_ERR(hdr))
1500 return PTR_ERR(hdr);
1501
1502 trans = psp_copy_user_blob(params.trans_uaddr, params.trans_len);
1503 if (IS_ERR(trans)) {
1504 ret = PTR_ERR(trans);
1505 goto e_free_hdr;
1506 }
1507
1508 memset(&data, 0, sizeof(data));
1509 data.hdr_address = __psp_pa(hdr);
1510 data.hdr_len = params.hdr_len;
1511 data.trans_address = __psp_pa(trans);
1512 data.trans_len = params.trans_len;
1513
1514 /* Pin guest memory */
1515 guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK,
1516 PAGE_SIZE, &n, 1);
1517 if (IS_ERR(guest_page)) {
1518 ret = PTR_ERR(guest_page);
1519 goto e_free_trans;
1520 }
1521
1522 /*
1523 * Flush (on non-coherent CPUs) before RECEIVE_UPDATE_DATA, the PSP
1524 * encrypts the written data with the guest's key, and the cache may
1525 * contain dirty, unencrypted data.
1526 */
1527 sev_clflush_pages(guest_page, n);
1528
1529 /* The RECEIVE_UPDATE_DATA command requires C-bit to be always set. */
1530 data.guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset;
1531 data.guest_address |= sev_me_mask;
1532 data.guest_len = params.guest_len;
1533 data.handle = sev->handle;
1534
1535 ret = sev_issue_cmd(kvm, SEV_CMD_RECEIVE_UPDATE_DATA, &data,
1536 &argp->error);
1537
1538 sev_unpin_memory(kvm, guest_page, n);
1539
1540 e_free_trans:
1541 kfree(trans);
1542 e_free_hdr:
1543 kfree(hdr);
1544
1545 return ret;
1546 }
1547
sev_receive_finish(struct kvm * kvm,struct kvm_sev_cmd * argp)1548 static int sev_receive_finish(struct kvm *kvm, struct kvm_sev_cmd *argp)
1549 {
1550 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1551 struct sev_data_receive_finish data;
1552
1553 if (!sev_guest(kvm))
1554 return -ENOTTY;
1555
1556 data.handle = sev->handle;
1557 return sev_issue_cmd(kvm, SEV_CMD_RECEIVE_FINISH, &data, &argp->error);
1558 }
1559
is_cmd_allowed_from_mirror(u32 cmd_id)1560 static bool is_cmd_allowed_from_mirror(u32 cmd_id)
1561 {
1562 /*
1563 * Allow mirrors VM to call KVM_SEV_LAUNCH_UPDATE_VMSA to enable SEV-ES
1564 * active mirror VMs. Also allow the debugging and status commands.
1565 */
1566 if (cmd_id == KVM_SEV_LAUNCH_UPDATE_VMSA ||
1567 cmd_id == KVM_SEV_GUEST_STATUS || cmd_id == KVM_SEV_DBG_DECRYPT ||
1568 cmd_id == KVM_SEV_DBG_ENCRYPT)
1569 return true;
1570
1571 return false;
1572 }
1573
sev_lock_two_vms(struct kvm * dst_kvm,struct kvm * src_kvm)1574 static int sev_lock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm)
1575 {
1576 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info;
1577 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info;
1578 int r = -EBUSY;
1579
1580 if (dst_kvm == src_kvm)
1581 return -EINVAL;
1582
1583 /*
1584 * Bail if these VMs are already involved in a migration to avoid
1585 * deadlock between two VMs trying to migrate to/from each other.
1586 */
1587 if (atomic_cmpxchg_acquire(&dst_sev->migration_in_progress, 0, 1))
1588 return -EBUSY;
1589
1590 if (atomic_cmpxchg_acquire(&src_sev->migration_in_progress, 0, 1))
1591 goto release_dst;
1592
1593 r = -EINTR;
1594 if (mutex_lock_killable(&dst_kvm->lock))
1595 goto release_src;
1596 if (mutex_lock_killable_nested(&src_kvm->lock, SINGLE_DEPTH_NESTING))
1597 goto unlock_dst;
1598 return 0;
1599
1600 unlock_dst:
1601 mutex_unlock(&dst_kvm->lock);
1602 release_src:
1603 atomic_set_release(&src_sev->migration_in_progress, 0);
1604 release_dst:
1605 atomic_set_release(&dst_sev->migration_in_progress, 0);
1606 return r;
1607 }
1608
sev_unlock_two_vms(struct kvm * dst_kvm,struct kvm * src_kvm)1609 static void sev_unlock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm)
1610 {
1611 struct kvm_sev_info *dst_sev = &to_kvm_svm(dst_kvm)->sev_info;
1612 struct kvm_sev_info *src_sev = &to_kvm_svm(src_kvm)->sev_info;
1613
1614 mutex_unlock(&dst_kvm->lock);
1615 mutex_unlock(&src_kvm->lock);
1616 atomic_set_release(&dst_sev->migration_in_progress, 0);
1617 atomic_set_release(&src_sev->migration_in_progress, 0);
1618 }
1619
1620 /* vCPU mutex subclasses. */
1621 enum sev_migration_role {
1622 SEV_MIGRATION_SOURCE = 0,
1623 SEV_MIGRATION_TARGET,
1624 SEV_NR_MIGRATION_ROLES,
1625 };
1626
sev_lock_vcpus_for_migration(struct kvm * kvm,enum sev_migration_role role)1627 static int sev_lock_vcpus_for_migration(struct kvm *kvm,
1628 enum sev_migration_role role)
1629 {
1630 struct kvm_vcpu *vcpu;
1631 unsigned long i, j;
1632
1633 kvm_for_each_vcpu(i, vcpu, kvm) {
1634 if (mutex_lock_killable_nested(&vcpu->mutex, role))
1635 goto out_unlock;
1636
1637 #ifdef CONFIG_PROVE_LOCKING
1638 if (!i)
1639 /*
1640 * Reset the role to one that avoids colliding with
1641 * the role used for the first vcpu mutex.
1642 */
1643 role = SEV_NR_MIGRATION_ROLES;
1644 else
1645 mutex_release(&vcpu->mutex.dep_map, _THIS_IP_);
1646 #endif
1647 }
1648
1649 return 0;
1650
1651 out_unlock:
1652
1653 kvm_for_each_vcpu(j, vcpu, kvm) {
1654 if (i == j)
1655 break;
1656
1657 #ifdef CONFIG_PROVE_LOCKING
1658 if (j)
1659 mutex_acquire(&vcpu->mutex.dep_map, role, 0, _THIS_IP_);
1660 #endif
1661
1662 mutex_unlock(&vcpu->mutex);
1663 }
1664 return -EINTR;
1665 }
1666
sev_unlock_vcpus_for_migration(struct kvm * kvm)1667 static void sev_unlock_vcpus_for_migration(struct kvm *kvm)
1668 {
1669 struct kvm_vcpu *vcpu;
1670 unsigned long i;
1671 bool first = true;
1672
1673 kvm_for_each_vcpu(i, vcpu, kvm) {
1674 if (first)
1675 first = false;
1676 else
1677 mutex_acquire(&vcpu->mutex.dep_map,
1678 SEV_NR_MIGRATION_ROLES, 0, _THIS_IP_);
1679
1680 mutex_unlock(&vcpu->mutex);
1681 }
1682 }
1683
sev_migrate_from(struct kvm * dst_kvm,struct kvm * src_kvm)1684 static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm)
1685 {
1686 struct kvm_sev_info *dst = &to_kvm_svm(dst_kvm)->sev_info;
1687 struct kvm_sev_info *src = &to_kvm_svm(src_kvm)->sev_info;
1688 struct kvm_vcpu *dst_vcpu, *src_vcpu;
1689 struct vcpu_svm *dst_svm, *src_svm;
1690 struct kvm_sev_info *mirror;
1691 unsigned long i;
1692
1693 dst->active = true;
1694 dst->asid = src->asid;
1695 dst->handle = src->handle;
1696 dst->pages_locked = src->pages_locked;
1697 dst->enc_context_owner = src->enc_context_owner;
1698 dst->es_active = src->es_active;
1699
1700 src->asid = 0;
1701 src->active = false;
1702 src->handle = 0;
1703 src->pages_locked = 0;
1704 src->enc_context_owner = NULL;
1705 src->es_active = false;
1706
1707 list_cut_before(&dst->regions_list, &src->regions_list, &src->regions_list);
1708
1709 /*
1710 * If this VM has mirrors, "transfer" each mirror's refcount of the
1711 * source to the destination (this KVM). The caller holds a reference
1712 * to the source, so there's no danger of use-after-free.
1713 */
1714 list_cut_before(&dst->mirror_vms, &src->mirror_vms, &src->mirror_vms);
1715 list_for_each_entry(mirror, &dst->mirror_vms, mirror_entry) {
1716 kvm_get_kvm(dst_kvm);
1717 kvm_put_kvm(src_kvm);
1718 mirror->enc_context_owner = dst_kvm;
1719 }
1720
1721 /*
1722 * If this VM is a mirror, remove the old mirror from the owners list
1723 * and add the new mirror to the list.
1724 */
1725 if (is_mirroring_enc_context(dst_kvm)) {
1726 struct kvm_sev_info *owner_sev_info =
1727 &to_kvm_svm(dst->enc_context_owner)->sev_info;
1728
1729 list_del(&src->mirror_entry);
1730 list_add_tail(&dst->mirror_entry, &owner_sev_info->mirror_vms);
1731 }
1732
1733 kvm_for_each_vcpu(i, dst_vcpu, dst_kvm) {
1734 dst_svm = to_svm(dst_vcpu);
1735
1736 sev_init_vmcb(dst_svm);
1737
1738 if (!dst->es_active)
1739 continue;
1740
1741 /*
1742 * Note, the source is not required to have the same number of
1743 * vCPUs as the destination when migrating a vanilla SEV VM.
1744 */
1745 src_vcpu = kvm_get_vcpu(src_kvm, i);
1746 src_svm = to_svm(src_vcpu);
1747
1748 /*
1749 * Transfer VMSA and GHCB state to the destination. Nullify and
1750 * clear source fields as appropriate, the state now belongs to
1751 * the destination.
1752 */
1753 memcpy(&dst_svm->sev_es, &src_svm->sev_es, sizeof(src_svm->sev_es));
1754 dst_svm->vmcb->control.ghcb_gpa = src_svm->vmcb->control.ghcb_gpa;
1755 dst_svm->vmcb->control.vmsa_pa = src_svm->vmcb->control.vmsa_pa;
1756 dst_vcpu->arch.guest_state_protected = true;
1757
1758 memset(&src_svm->sev_es, 0, sizeof(src_svm->sev_es));
1759 src_svm->vmcb->control.ghcb_gpa = INVALID_PAGE;
1760 src_svm->vmcb->control.vmsa_pa = INVALID_PAGE;
1761 src_vcpu->arch.guest_state_protected = false;
1762 }
1763 }
1764
sev_check_source_vcpus(struct kvm * dst,struct kvm * src)1765 static int sev_check_source_vcpus(struct kvm *dst, struct kvm *src)
1766 {
1767 struct kvm_vcpu *src_vcpu;
1768 unsigned long i;
1769
1770 if (!sev_es_guest(src))
1771 return 0;
1772
1773 if (atomic_read(&src->online_vcpus) != atomic_read(&dst->online_vcpus))
1774 return -EINVAL;
1775
1776 kvm_for_each_vcpu(i, src_vcpu, src) {
1777 if (!src_vcpu->arch.guest_state_protected)
1778 return -EINVAL;
1779 }
1780
1781 return 0;
1782 }
1783
sev_vm_move_enc_context_from(struct kvm * kvm,unsigned int source_fd)1784 int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd)
1785 {
1786 struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info;
1787 struct kvm_sev_info *src_sev, *cg_cleanup_sev;
1788 struct fd f = fdget(source_fd);
1789 struct kvm *source_kvm;
1790 bool charged = false;
1791 int ret;
1792
1793 if (!f.file)
1794 return -EBADF;
1795
1796 if (!file_is_kvm(f.file)) {
1797 ret = -EBADF;
1798 goto out_fput;
1799 }
1800
1801 source_kvm = f.file->private_data;
1802 ret = sev_lock_two_vms(kvm, source_kvm);
1803 if (ret)
1804 goto out_fput;
1805
1806 if (sev_guest(kvm) || !sev_guest(source_kvm)) {
1807 ret = -EINVAL;
1808 goto out_unlock;
1809 }
1810
1811 src_sev = &to_kvm_svm(source_kvm)->sev_info;
1812
1813 dst_sev->misc_cg = get_current_misc_cg();
1814 cg_cleanup_sev = dst_sev;
1815 if (dst_sev->misc_cg != src_sev->misc_cg) {
1816 ret = sev_misc_cg_try_charge(dst_sev);
1817 if (ret)
1818 goto out_dst_cgroup;
1819 charged = true;
1820 }
1821
1822 ret = sev_lock_vcpus_for_migration(kvm, SEV_MIGRATION_SOURCE);
1823 if (ret)
1824 goto out_dst_cgroup;
1825 ret = sev_lock_vcpus_for_migration(source_kvm, SEV_MIGRATION_TARGET);
1826 if (ret)
1827 goto out_dst_vcpu;
1828
1829 ret = sev_check_source_vcpus(kvm, source_kvm);
1830 if (ret)
1831 goto out_source_vcpu;
1832
1833 sev_migrate_from(kvm, source_kvm);
1834 kvm_vm_dead(source_kvm);
1835 cg_cleanup_sev = src_sev;
1836 ret = 0;
1837
1838 out_source_vcpu:
1839 sev_unlock_vcpus_for_migration(source_kvm);
1840 out_dst_vcpu:
1841 sev_unlock_vcpus_for_migration(kvm);
1842 out_dst_cgroup:
1843 /* Operates on the source on success, on the destination on failure. */
1844 if (charged)
1845 sev_misc_cg_uncharge(cg_cleanup_sev);
1846 put_misc_cg(cg_cleanup_sev->misc_cg);
1847 cg_cleanup_sev->misc_cg = NULL;
1848 out_unlock:
1849 sev_unlock_two_vms(kvm, source_kvm);
1850 out_fput:
1851 fdput(f);
1852 return ret;
1853 }
1854
sev_mem_enc_ioctl(struct kvm * kvm,void __user * argp)1855 int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
1856 {
1857 struct kvm_sev_cmd sev_cmd;
1858 int r;
1859
1860 if (!sev_enabled)
1861 return -ENOTTY;
1862
1863 if (!argp)
1864 return 0;
1865
1866 if (copy_from_user(&sev_cmd, argp, sizeof(struct kvm_sev_cmd)))
1867 return -EFAULT;
1868
1869 mutex_lock(&kvm->lock);
1870
1871 /* Only the enc_context_owner handles some memory enc operations. */
1872 if (is_mirroring_enc_context(kvm) &&
1873 !is_cmd_allowed_from_mirror(sev_cmd.id)) {
1874 r = -EINVAL;
1875 goto out;
1876 }
1877
1878 switch (sev_cmd.id) {
1879 case KVM_SEV_ES_INIT:
1880 if (!sev_es_enabled) {
1881 r = -ENOTTY;
1882 goto out;
1883 }
1884 fallthrough;
1885 case KVM_SEV_INIT:
1886 r = sev_guest_init(kvm, &sev_cmd);
1887 break;
1888 case KVM_SEV_LAUNCH_START:
1889 r = sev_launch_start(kvm, &sev_cmd);
1890 break;
1891 case KVM_SEV_LAUNCH_UPDATE_DATA:
1892 r = sev_launch_update_data(kvm, &sev_cmd);
1893 break;
1894 case KVM_SEV_LAUNCH_UPDATE_VMSA:
1895 r = sev_launch_update_vmsa(kvm, &sev_cmd);
1896 break;
1897 case KVM_SEV_LAUNCH_MEASURE:
1898 r = sev_launch_measure(kvm, &sev_cmd);
1899 break;
1900 case KVM_SEV_LAUNCH_FINISH:
1901 r = sev_launch_finish(kvm, &sev_cmd);
1902 break;
1903 case KVM_SEV_GUEST_STATUS:
1904 r = sev_guest_status(kvm, &sev_cmd);
1905 break;
1906 case KVM_SEV_DBG_DECRYPT:
1907 r = sev_dbg_crypt(kvm, &sev_cmd, true);
1908 break;
1909 case KVM_SEV_DBG_ENCRYPT:
1910 r = sev_dbg_crypt(kvm, &sev_cmd, false);
1911 break;
1912 case KVM_SEV_LAUNCH_SECRET:
1913 r = sev_launch_secret(kvm, &sev_cmd);
1914 break;
1915 case KVM_SEV_GET_ATTESTATION_REPORT:
1916 r = sev_get_attestation_report(kvm, &sev_cmd);
1917 break;
1918 case KVM_SEV_SEND_START:
1919 r = sev_send_start(kvm, &sev_cmd);
1920 break;
1921 case KVM_SEV_SEND_UPDATE_DATA:
1922 r = sev_send_update_data(kvm, &sev_cmd);
1923 break;
1924 case KVM_SEV_SEND_FINISH:
1925 r = sev_send_finish(kvm, &sev_cmd);
1926 break;
1927 case KVM_SEV_SEND_CANCEL:
1928 r = sev_send_cancel(kvm, &sev_cmd);
1929 break;
1930 case KVM_SEV_RECEIVE_START:
1931 r = sev_receive_start(kvm, &sev_cmd);
1932 break;
1933 case KVM_SEV_RECEIVE_UPDATE_DATA:
1934 r = sev_receive_update_data(kvm, &sev_cmd);
1935 break;
1936 case KVM_SEV_RECEIVE_FINISH:
1937 r = sev_receive_finish(kvm, &sev_cmd);
1938 break;
1939 default:
1940 r = -EINVAL;
1941 goto out;
1942 }
1943
1944 if (copy_to_user(argp, &sev_cmd, sizeof(struct kvm_sev_cmd)))
1945 r = -EFAULT;
1946
1947 out:
1948 mutex_unlock(&kvm->lock);
1949 return r;
1950 }
1951
sev_mem_enc_register_region(struct kvm * kvm,struct kvm_enc_region * range)1952 int sev_mem_enc_register_region(struct kvm *kvm,
1953 struct kvm_enc_region *range)
1954 {
1955 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
1956 struct enc_region *region;
1957 int ret = 0;
1958
1959 if (!sev_guest(kvm))
1960 return -ENOTTY;
1961
1962 /* If kvm is mirroring encryption context it isn't responsible for it */
1963 if (is_mirroring_enc_context(kvm))
1964 return -EINVAL;
1965
1966 if (range->addr > ULONG_MAX || range->size > ULONG_MAX)
1967 return -EINVAL;
1968
1969 region = kzalloc(sizeof(*region), GFP_KERNEL_ACCOUNT);
1970 if (!region)
1971 return -ENOMEM;
1972
1973 mutex_lock(&kvm->lock);
1974 region->pages = sev_pin_memory(kvm, range->addr, range->size, ®ion->npages, 1);
1975 if (IS_ERR(region->pages)) {
1976 ret = PTR_ERR(region->pages);
1977 mutex_unlock(&kvm->lock);
1978 goto e_free;
1979 }
1980
1981 /*
1982 * The guest may change the memory encryption attribute from C=0 -> C=1
1983 * or vice versa for this memory range. Lets make sure caches are
1984 * flushed to ensure that guest data gets written into memory with
1985 * correct C-bit. Note, this must be done before dropping kvm->lock,
1986 * as region and its array of pages can be freed by a different task
1987 * once kvm->lock is released.
1988 */
1989 sev_clflush_pages(region->pages, region->npages);
1990
1991 region->uaddr = range->addr;
1992 region->size = range->size;
1993
1994 list_add_tail(®ion->list, &sev->regions_list);
1995 mutex_unlock(&kvm->lock);
1996
1997 return ret;
1998
1999 e_free:
2000 kfree(region);
2001 return ret;
2002 }
2003
2004 static struct enc_region *
find_enc_region(struct kvm * kvm,struct kvm_enc_region * range)2005 find_enc_region(struct kvm *kvm, struct kvm_enc_region *range)
2006 {
2007 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
2008 struct list_head *head = &sev->regions_list;
2009 struct enc_region *i;
2010
2011 list_for_each_entry(i, head, list) {
2012 if (i->uaddr == range->addr &&
2013 i->size == range->size)
2014 return i;
2015 }
2016
2017 return NULL;
2018 }
2019
__unregister_enc_region_locked(struct kvm * kvm,struct enc_region * region)2020 static void __unregister_enc_region_locked(struct kvm *kvm,
2021 struct enc_region *region)
2022 {
2023 sev_unpin_memory(kvm, region->pages, region->npages);
2024 list_del(®ion->list);
2025 kfree(region);
2026 }
2027
sev_mem_enc_unregister_region(struct kvm * kvm,struct kvm_enc_region * range)2028 int sev_mem_enc_unregister_region(struct kvm *kvm,
2029 struct kvm_enc_region *range)
2030 {
2031 struct enc_region *region;
2032 int ret;
2033
2034 /* If kvm is mirroring encryption context it isn't responsible for it */
2035 if (is_mirroring_enc_context(kvm))
2036 return -EINVAL;
2037
2038 mutex_lock(&kvm->lock);
2039
2040 if (!sev_guest(kvm)) {
2041 ret = -ENOTTY;
2042 goto failed;
2043 }
2044
2045 region = find_enc_region(kvm, range);
2046 if (!region) {
2047 ret = -EINVAL;
2048 goto failed;
2049 }
2050
2051 /*
2052 * Ensure that all guest tagged cache entries are flushed before
2053 * releasing the pages back to the system for use. CLFLUSH will
2054 * not do this, so issue a WBINVD.
2055 */
2056 wbinvd_on_all_cpus();
2057
2058 __unregister_enc_region_locked(kvm, region);
2059
2060 mutex_unlock(&kvm->lock);
2061 return 0;
2062
2063 failed:
2064 mutex_unlock(&kvm->lock);
2065 return ret;
2066 }
2067
sev_vm_copy_enc_context_from(struct kvm * kvm,unsigned int source_fd)2068 int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd)
2069 {
2070 struct fd f = fdget(source_fd);
2071 struct kvm *source_kvm;
2072 struct kvm_sev_info *source_sev, *mirror_sev;
2073 int ret;
2074
2075 if (!f.file)
2076 return -EBADF;
2077
2078 if (!file_is_kvm(f.file)) {
2079 ret = -EBADF;
2080 goto e_source_fput;
2081 }
2082
2083 source_kvm = f.file->private_data;
2084 ret = sev_lock_two_vms(kvm, source_kvm);
2085 if (ret)
2086 goto e_source_fput;
2087
2088 /*
2089 * Mirrors of mirrors should work, but let's not get silly. Also
2090 * disallow out-of-band SEV/SEV-ES init if the target is already an
2091 * SEV guest, or if vCPUs have been created. KVM relies on vCPUs being
2092 * created after SEV/SEV-ES initialization, e.g. to init intercepts.
2093 */
2094 if (sev_guest(kvm) || !sev_guest(source_kvm) ||
2095 is_mirroring_enc_context(source_kvm) || kvm->created_vcpus) {
2096 ret = -EINVAL;
2097 goto e_unlock;
2098 }
2099
2100 /*
2101 * The mirror kvm holds an enc_context_owner ref so its asid can't
2102 * disappear until we're done with it
2103 */
2104 source_sev = &to_kvm_svm(source_kvm)->sev_info;
2105 kvm_get_kvm(source_kvm);
2106 mirror_sev = &to_kvm_svm(kvm)->sev_info;
2107 list_add_tail(&mirror_sev->mirror_entry, &source_sev->mirror_vms);
2108
2109 /* Set enc_context_owner and copy its encryption context over */
2110 mirror_sev->enc_context_owner = source_kvm;
2111 mirror_sev->active = true;
2112 mirror_sev->asid = source_sev->asid;
2113 mirror_sev->fd = source_sev->fd;
2114 mirror_sev->es_active = source_sev->es_active;
2115 mirror_sev->handle = source_sev->handle;
2116 INIT_LIST_HEAD(&mirror_sev->regions_list);
2117 INIT_LIST_HEAD(&mirror_sev->mirror_vms);
2118 ret = 0;
2119
2120 /*
2121 * Do not copy ap_jump_table. Since the mirror does not share the same
2122 * KVM contexts as the original, and they may have different
2123 * memory-views.
2124 */
2125
2126 e_unlock:
2127 sev_unlock_two_vms(kvm, source_kvm);
2128 e_source_fput:
2129 fdput(f);
2130 return ret;
2131 }
2132
sev_vm_destroy(struct kvm * kvm)2133 void sev_vm_destroy(struct kvm *kvm)
2134 {
2135 struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
2136 struct list_head *head = &sev->regions_list;
2137 struct list_head *pos, *q;
2138
2139 if (!sev_guest(kvm))
2140 return;
2141
2142 WARN_ON(!list_empty(&sev->mirror_vms));
2143
2144 /* If this is a mirror_kvm release the enc_context_owner and skip sev cleanup */
2145 if (is_mirroring_enc_context(kvm)) {
2146 struct kvm *owner_kvm = sev->enc_context_owner;
2147
2148 mutex_lock(&owner_kvm->lock);
2149 list_del(&sev->mirror_entry);
2150 mutex_unlock(&owner_kvm->lock);
2151 kvm_put_kvm(owner_kvm);
2152 return;
2153 }
2154
2155 /*
2156 * Ensure that all guest tagged cache entries are flushed before
2157 * releasing the pages back to the system for use. CLFLUSH will
2158 * not do this, so issue a WBINVD.
2159 */
2160 wbinvd_on_all_cpus();
2161
2162 /*
2163 * if userspace was terminated before unregistering the memory regions
2164 * then lets unpin all the registered memory.
2165 */
2166 if (!list_empty(head)) {
2167 list_for_each_safe(pos, q, head) {
2168 __unregister_enc_region_locked(kvm,
2169 list_entry(pos, struct enc_region, list));
2170 cond_resched();
2171 }
2172 }
2173
2174 sev_unbind_asid(kvm, sev->handle);
2175 sev_asid_free(sev);
2176 }
2177
sev_set_cpu_caps(void)2178 void __init sev_set_cpu_caps(void)
2179 {
2180 if (!sev_enabled)
2181 kvm_cpu_cap_clear(X86_FEATURE_SEV);
2182 if (!sev_es_enabled)
2183 kvm_cpu_cap_clear(X86_FEATURE_SEV_ES);
2184 }
2185
sev_hardware_setup(void)2186 void __init sev_hardware_setup(void)
2187 {
2188 #ifdef CONFIG_KVM_AMD_SEV
2189 unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count;
2190 bool sev_es_supported = false;
2191 bool sev_supported = false;
2192
2193 if (!sev_enabled || !npt_enabled || !nrips)
2194 goto out;
2195
2196 /*
2197 * SEV must obviously be supported in hardware. Sanity check that the
2198 * CPU supports decode assists, which is mandatory for SEV guests to
2199 * support instruction emulation. Ditto for flushing by ASID, as SEV
2200 * guests are bound to a single ASID, i.e. KVM can't rotate to a new
2201 * ASID to effect a TLB flush.
2202 */
2203 if (!boot_cpu_has(X86_FEATURE_SEV) ||
2204 WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_DECODEASSISTS)) ||
2205 WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_FLUSHBYASID)))
2206 goto out;
2207
2208 /* Retrieve SEV CPUID information */
2209 cpuid(0x8000001f, &eax, &ebx, &ecx, &edx);
2210
2211 /* Set encryption bit location for SEV-ES guests */
2212 sev_enc_bit = ebx & 0x3f;
2213
2214 /* Maximum number of encrypted guests supported simultaneously */
2215 max_sev_asid = ecx;
2216 if (!max_sev_asid)
2217 goto out;
2218
2219 /* Minimum ASID value that should be used for SEV guest */
2220 min_sev_asid = edx;
2221 sev_me_mask = 1UL << (ebx & 0x3f);
2222
2223 /*
2224 * Initialize SEV ASID bitmaps. Allocate space for ASID 0 in the bitmap,
2225 * even though it's never used, so that the bitmap is indexed by the
2226 * actual ASID.
2227 */
2228 nr_asids = max_sev_asid + 1;
2229 sev_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL);
2230 if (!sev_asid_bitmap)
2231 goto out;
2232
2233 sev_reclaim_asid_bitmap = bitmap_zalloc(nr_asids, GFP_KERNEL);
2234 if (!sev_reclaim_asid_bitmap) {
2235 bitmap_free(sev_asid_bitmap);
2236 sev_asid_bitmap = NULL;
2237 goto out;
2238 }
2239
2240 sev_asid_count = max_sev_asid - min_sev_asid + 1;
2241 WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV, sev_asid_count));
2242 sev_supported = true;
2243
2244 /* SEV-ES support requested? */
2245 if (!sev_es_enabled)
2246 goto out;
2247
2248 /*
2249 * SEV-ES requires MMIO caching as KVM doesn't have access to the guest
2250 * instruction stream, i.e. can't emulate in response to a #NPF and
2251 * instead relies on #NPF(RSVD) being reflected into the guest as #VC
2252 * (the guest can then do a #VMGEXIT to request MMIO emulation).
2253 */
2254 if (!enable_mmio_caching)
2255 goto out;
2256
2257 /* Does the CPU support SEV-ES? */
2258 if (!boot_cpu_has(X86_FEATURE_SEV_ES))
2259 goto out;
2260
2261 /* Has the system been allocated ASIDs for SEV-ES? */
2262 if (min_sev_asid == 1)
2263 goto out;
2264
2265 sev_es_asid_count = min_sev_asid - 1;
2266 WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV_ES, sev_es_asid_count));
2267 sev_es_supported = true;
2268
2269 out:
2270 if (boot_cpu_has(X86_FEATURE_SEV))
2271 pr_info("SEV %s (ASIDs %u - %u)\n",
2272 sev_supported ? "enabled" : "disabled",
2273 min_sev_asid, max_sev_asid);
2274 if (boot_cpu_has(X86_FEATURE_SEV_ES))
2275 pr_info("SEV-ES %s (ASIDs %u - %u)\n",
2276 sev_es_supported ? "enabled" : "disabled",
2277 min_sev_asid > 1 ? 1 : 0, min_sev_asid - 1);
2278
2279 sev_enabled = sev_supported;
2280 sev_es_enabled = sev_es_supported;
2281 if (!sev_es_enabled || !cpu_feature_enabled(X86_FEATURE_DEBUG_SWAP) ||
2282 !cpu_feature_enabled(X86_FEATURE_NO_NESTED_DATA_BP))
2283 sev_es_debug_swap_enabled = false;
2284 #endif
2285 }
2286
sev_hardware_unsetup(void)2287 void sev_hardware_unsetup(void)
2288 {
2289 if (!sev_enabled)
2290 return;
2291
2292 /* No need to take sev_bitmap_lock, all VMs have been destroyed. */
2293 sev_flush_asids(1, max_sev_asid);
2294
2295 bitmap_free(sev_asid_bitmap);
2296 bitmap_free(sev_reclaim_asid_bitmap);
2297
2298 misc_cg_set_capacity(MISC_CG_RES_SEV, 0);
2299 misc_cg_set_capacity(MISC_CG_RES_SEV_ES, 0);
2300 }
2301
sev_cpu_init(struct svm_cpu_data * sd)2302 int sev_cpu_init(struct svm_cpu_data *sd)
2303 {
2304 if (!sev_enabled)
2305 return 0;
2306
2307 sd->sev_vmcbs = kcalloc(nr_asids, sizeof(void *), GFP_KERNEL);
2308 if (!sd->sev_vmcbs)
2309 return -ENOMEM;
2310
2311 return 0;
2312 }
2313
2314 /*
2315 * Pages used by hardware to hold guest encrypted state must be flushed before
2316 * returning them to the system.
2317 */
sev_flush_encrypted_page(struct kvm_vcpu * vcpu,void * va)2318 static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va)
2319 {
2320 int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid;
2321
2322 /*
2323 * Note! The address must be a kernel address, as regular page walk
2324 * checks are performed by VM_PAGE_FLUSH, i.e. operating on a user
2325 * address is non-deterministic and unsafe. This function deliberately
2326 * takes a pointer to deter passing in a user address.
2327 */
2328 unsigned long addr = (unsigned long)va;
2329
2330 /*
2331 * If CPU enforced cache coherency for encrypted mappings of the
2332 * same physical page is supported, use CLFLUSHOPT instead. NOTE: cache
2333 * flush is still needed in order to work properly with DMA devices.
2334 */
2335 if (boot_cpu_has(X86_FEATURE_SME_COHERENT)) {
2336 clflush_cache_range(va, PAGE_SIZE);
2337 return;
2338 }
2339
2340 /*
2341 * VM Page Flush takes a host virtual address and a guest ASID. Fall
2342 * back to WBINVD if this faults so as not to make any problems worse
2343 * by leaving stale encrypted data in the cache.
2344 */
2345 if (WARN_ON_ONCE(wrmsrl_safe(MSR_AMD64_VM_PAGE_FLUSH, addr | asid)))
2346 goto do_wbinvd;
2347
2348 return;
2349
2350 do_wbinvd:
2351 wbinvd_on_all_cpus();
2352 }
2353
sev_guest_memory_reclaimed(struct kvm * kvm)2354 void sev_guest_memory_reclaimed(struct kvm *kvm)
2355 {
2356 if (!sev_guest(kvm))
2357 return;
2358
2359 wbinvd_on_all_cpus();
2360 }
2361
sev_free_vcpu(struct kvm_vcpu * vcpu)2362 void sev_free_vcpu(struct kvm_vcpu *vcpu)
2363 {
2364 struct vcpu_svm *svm;
2365
2366 if (!sev_es_guest(vcpu->kvm))
2367 return;
2368
2369 svm = to_svm(vcpu);
2370
2371 if (vcpu->arch.guest_state_protected)
2372 sev_flush_encrypted_page(vcpu, svm->sev_es.vmsa);
2373
2374 __free_page(virt_to_page(svm->sev_es.vmsa));
2375
2376 if (svm->sev_es.ghcb_sa_free)
2377 kvfree(svm->sev_es.ghcb_sa);
2378 }
2379
dump_ghcb(struct vcpu_svm * svm)2380 static void dump_ghcb(struct vcpu_svm *svm)
2381 {
2382 struct ghcb *ghcb = svm->sev_es.ghcb;
2383 unsigned int nbits;
2384
2385 /* Re-use the dump_invalid_vmcb module parameter */
2386 if (!dump_invalid_vmcb) {
2387 pr_warn_ratelimited("set kvm_amd.dump_invalid_vmcb=1 to dump internal KVM state.\n");
2388 return;
2389 }
2390
2391 nbits = sizeof(ghcb->save.valid_bitmap) * 8;
2392
2393 pr_err("GHCB (GPA=%016llx):\n", svm->vmcb->control.ghcb_gpa);
2394 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_code",
2395 ghcb->save.sw_exit_code, ghcb_sw_exit_code_is_valid(ghcb));
2396 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_1",
2397 ghcb->save.sw_exit_info_1, ghcb_sw_exit_info_1_is_valid(ghcb));
2398 pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_2",
2399 ghcb->save.sw_exit_info_2, ghcb_sw_exit_info_2_is_valid(ghcb));
2400 pr_err("%-20s%016llx is_valid: %u\n", "sw_scratch",
2401 ghcb->save.sw_scratch, ghcb_sw_scratch_is_valid(ghcb));
2402 pr_err("%-20s%*pb\n", "valid_bitmap", nbits, ghcb->save.valid_bitmap);
2403 }
2404
sev_es_sync_to_ghcb(struct vcpu_svm * svm)2405 static void sev_es_sync_to_ghcb(struct vcpu_svm *svm)
2406 {
2407 struct kvm_vcpu *vcpu = &svm->vcpu;
2408 struct ghcb *ghcb = svm->sev_es.ghcb;
2409
2410 /*
2411 * The GHCB protocol so far allows for the following data
2412 * to be returned:
2413 * GPRs RAX, RBX, RCX, RDX
2414 *
2415 * Copy their values, even if they may not have been written during the
2416 * VM-Exit. It's the guest's responsibility to not consume random data.
2417 */
2418 ghcb_set_rax(ghcb, vcpu->arch.regs[VCPU_REGS_RAX]);
2419 ghcb_set_rbx(ghcb, vcpu->arch.regs[VCPU_REGS_RBX]);
2420 ghcb_set_rcx(ghcb, vcpu->arch.regs[VCPU_REGS_RCX]);
2421 ghcb_set_rdx(ghcb, vcpu->arch.regs[VCPU_REGS_RDX]);
2422 }
2423
sev_es_sync_from_ghcb(struct vcpu_svm * svm)2424 static void sev_es_sync_from_ghcb(struct vcpu_svm *svm)
2425 {
2426 struct vmcb_control_area *control = &svm->vmcb->control;
2427 struct kvm_vcpu *vcpu = &svm->vcpu;
2428 struct ghcb *ghcb = svm->sev_es.ghcb;
2429 u64 exit_code;
2430
2431 /*
2432 * The GHCB protocol so far allows for the following data
2433 * to be supplied:
2434 * GPRs RAX, RBX, RCX, RDX
2435 * XCR0
2436 * CPL
2437 *
2438 * VMMCALL allows the guest to provide extra registers. KVM also
2439 * expects RSI for hypercalls, so include that, too.
2440 *
2441 * Copy their values to the appropriate location if supplied.
2442 */
2443 memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs));
2444
2445 BUILD_BUG_ON(sizeof(svm->sev_es.valid_bitmap) != sizeof(ghcb->save.valid_bitmap));
2446 memcpy(&svm->sev_es.valid_bitmap, &ghcb->save.valid_bitmap, sizeof(ghcb->save.valid_bitmap));
2447
2448 vcpu->arch.regs[VCPU_REGS_RAX] = kvm_ghcb_get_rax_if_valid(svm, ghcb);
2449 vcpu->arch.regs[VCPU_REGS_RBX] = kvm_ghcb_get_rbx_if_valid(svm, ghcb);
2450 vcpu->arch.regs[VCPU_REGS_RCX] = kvm_ghcb_get_rcx_if_valid(svm, ghcb);
2451 vcpu->arch.regs[VCPU_REGS_RDX] = kvm_ghcb_get_rdx_if_valid(svm, ghcb);
2452 vcpu->arch.regs[VCPU_REGS_RSI] = kvm_ghcb_get_rsi_if_valid(svm, ghcb);
2453
2454 svm->vmcb->save.cpl = kvm_ghcb_get_cpl_if_valid(svm, ghcb);
2455
2456 if (kvm_ghcb_xcr0_is_valid(svm)) {
2457 vcpu->arch.xcr0 = ghcb_get_xcr0(ghcb);
2458 kvm_update_cpuid_runtime(vcpu);
2459 }
2460
2461 /* Copy the GHCB exit information into the VMCB fields */
2462 exit_code = ghcb_get_sw_exit_code(ghcb);
2463 control->exit_code = lower_32_bits(exit_code);
2464 control->exit_code_hi = upper_32_bits(exit_code);
2465 control->exit_info_1 = ghcb_get_sw_exit_info_1(ghcb);
2466 control->exit_info_2 = ghcb_get_sw_exit_info_2(ghcb);
2467 svm->sev_es.sw_scratch = kvm_ghcb_get_sw_scratch_if_valid(svm, ghcb);
2468
2469 /* Clear the valid entries fields */
2470 memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap));
2471 }
2472
kvm_ghcb_get_sw_exit_code(struct vmcb_control_area * control)2473 static u64 kvm_ghcb_get_sw_exit_code(struct vmcb_control_area *control)
2474 {
2475 return (((u64)control->exit_code_hi) << 32) | control->exit_code;
2476 }
2477
sev_es_validate_vmgexit(struct vcpu_svm * svm)2478 static int sev_es_validate_vmgexit(struct vcpu_svm *svm)
2479 {
2480 struct vmcb_control_area *control = &svm->vmcb->control;
2481 struct kvm_vcpu *vcpu = &svm->vcpu;
2482 u64 exit_code;
2483 u64 reason;
2484
2485 /*
2486 * Retrieve the exit code now even though it may not be marked valid
2487 * as it could help with debugging.
2488 */
2489 exit_code = kvm_ghcb_get_sw_exit_code(control);
2490
2491 /* Only GHCB Usage code 0 is supported */
2492 if (svm->sev_es.ghcb->ghcb_usage) {
2493 reason = GHCB_ERR_INVALID_USAGE;
2494 goto vmgexit_err;
2495 }
2496
2497 reason = GHCB_ERR_MISSING_INPUT;
2498
2499 if (!kvm_ghcb_sw_exit_code_is_valid(svm) ||
2500 !kvm_ghcb_sw_exit_info_1_is_valid(svm) ||
2501 !kvm_ghcb_sw_exit_info_2_is_valid(svm))
2502 goto vmgexit_err;
2503
2504 switch (exit_code) {
2505 case SVM_EXIT_READ_DR7:
2506 break;
2507 case SVM_EXIT_WRITE_DR7:
2508 if (!kvm_ghcb_rax_is_valid(svm))
2509 goto vmgexit_err;
2510 break;
2511 case SVM_EXIT_RDTSC:
2512 break;
2513 case SVM_EXIT_RDPMC:
2514 if (!kvm_ghcb_rcx_is_valid(svm))
2515 goto vmgexit_err;
2516 break;
2517 case SVM_EXIT_CPUID:
2518 if (!kvm_ghcb_rax_is_valid(svm) ||
2519 !kvm_ghcb_rcx_is_valid(svm))
2520 goto vmgexit_err;
2521 if (vcpu->arch.regs[VCPU_REGS_RAX] == 0xd)
2522 if (!kvm_ghcb_xcr0_is_valid(svm))
2523 goto vmgexit_err;
2524 break;
2525 case SVM_EXIT_INVD:
2526 break;
2527 case SVM_EXIT_IOIO:
2528 if (control->exit_info_1 & SVM_IOIO_STR_MASK) {
2529 if (!kvm_ghcb_sw_scratch_is_valid(svm))
2530 goto vmgexit_err;
2531 } else {
2532 if (!(control->exit_info_1 & SVM_IOIO_TYPE_MASK))
2533 if (!kvm_ghcb_rax_is_valid(svm))
2534 goto vmgexit_err;
2535 }
2536 break;
2537 case SVM_EXIT_MSR:
2538 if (!kvm_ghcb_rcx_is_valid(svm))
2539 goto vmgexit_err;
2540 if (control->exit_info_1) {
2541 if (!kvm_ghcb_rax_is_valid(svm) ||
2542 !kvm_ghcb_rdx_is_valid(svm))
2543 goto vmgexit_err;
2544 }
2545 break;
2546 case SVM_EXIT_VMMCALL:
2547 if (!kvm_ghcb_rax_is_valid(svm) ||
2548 !kvm_ghcb_cpl_is_valid(svm))
2549 goto vmgexit_err;
2550 break;
2551 case SVM_EXIT_RDTSCP:
2552 break;
2553 case SVM_EXIT_WBINVD:
2554 break;
2555 case SVM_EXIT_MONITOR:
2556 if (!kvm_ghcb_rax_is_valid(svm) ||
2557 !kvm_ghcb_rcx_is_valid(svm) ||
2558 !kvm_ghcb_rdx_is_valid(svm))
2559 goto vmgexit_err;
2560 break;
2561 case SVM_EXIT_MWAIT:
2562 if (!kvm_ghcb_rax_is_valid(svm) ||
2563 !kvm_ghcb_rcx_is_valid(svm))
2564 goto vmgexit_err;
2565 break;
2566 case SVM_VMGEXIT_MMIO_READ:
2567 case SVM_VMGEXIT_MMIO_WRITE:
2568 if (!kvm_ghcb_sw_scratch_is_valid(svm))
2569 goto vmgexit_err;
2570 break;
2571 case SVM_VMGEXIT_NMI_COMPLETE:
2572 case SVM_VMGEXIT_AP_HLT_LOOP:
2573 case SVM_VMGEXIT_AP_JUMP_TABLE:
2574 case SVM_VMGEXIT_UNSUPPORTED_EVENT:
2575 break;
2576 default:
2577 reason = GHCB_ERR_INVALID_EVENT;
2578 goto vmgexit_err;
2579 }
2580
2581 return 0;
2582
2583 vmgexit_err:
2584 if (reason == GHCB_ERR_INVALID_USAGE) {
2585 vcpu_unimpl(vcpu, "vmgexit: ghcb usage %#x is not valid\n",
2586 svm->sev_es.ghcb->ghcb_usage);
2587 } else if (reason == GHCB_ERR_INVALID_EVENT) {
2588 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx is not valid\n",
2589 exit_code);
2590 } else {
2591 vcpu_unimpl(vcpu, "vmgexit: exit code %#llx input is not valid\n",
2592 exit_code);
2593 dump_ghcb(svm);
2594 }
2595
2596 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2);
2597 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, reason);
2598
2599 /* Resume the guest to "return" the error code. */
2600 return 1;
2601 }
2602
sev_es_unmap_ghcb(struct vcpu_svm * svm)2603 void sev_es_unmap_ghcb(struct vcpu_svm *svm)
2604 {
2605 if (!svm->sev_es.ghcb)
2606 return;
2607
2608 if (svm->sev_es.ghcb_sa_free) {
2609 /*
2610 * The scratch area lives outside the GHCB, so there is a
2611 * buffer that, depending on the operation performed, may
2612 * need to be synced, then freed.
2613 */
2614 if (svm->sev_es.ghcb_sa_sync) {
2615 kvm_write_guest(svm->vcpu.kvm,
2616 svm->sev_es.sw_scratch,
2617 svm->sev_es.ghcb_sa,
2618 svm->sev_es.ghcb_sa_len);
2619 svm->sev_es.ghcb_sa_sync = false;
2620 }
2621
2622 kvfree(svm->sev_es.ghcb_sa);
2623 svm->sev_es.ghcb_sa = NULL;
2624 svm->sev_es.ghcb_sa_free = false;
2625 }
2626
2627 trace_kvm_vmgexit_exit(svm->vcpu.vcpu_id, svm->sev_es.ghcb);
2628
2629 sev_es_sync_to_ghcb(svm);
2630
2631 kvm_vcpu_unmap(&svm->vcpu, &svm->sev_es.ghcb_map, true);
2632 svm->sev_es.ghcb = NULL;
2633 }
2634
pre_sev_run(struct vcpu_svm * svm,int cpu)2635 void pre_sev_run(struct vcpu_svm *svm, int cpu)
2636 {
2637 struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu);
2638 int asid = sev_get_asid(svm->vcpu.kvm);
2639
2640 /* Assign the asid allocated with this SEV guest */
2641 svm->asid = asid;
2642
2643 /*
2644 * Flush guest TLB:
2645 *
2646 * 1) when different VMCB for the same ASID is to be run on the same host CPU.
2647 * 2) or this VMCB was executed on different host CPU in previous VMRUNs.
2648 */
2649 if (sd->sev_vmcbs[asid] == svm->vmcb &&
2650 svm->vcpu.arch.last_vmentry_cpu == cpu)
2651 return;
2652
2653 sd->sev_vmcbs[asid] = svm->vmcb;
2654 svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID;
2655 vmcb_mark_dirty(svm->vmcb, VMCB_ASID);
2656 }
2657
2658 #define GHCB_SCRATCH_AREA_LIMIT (16ULL * PAGE_SIZE)
setup_vmgexit_scratch(struct vcpu_svm * svm,bool sync,u64 len)2659 static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len)
2660 {
2661 struct vmcb_control_area *control = &svm->vmcb->control;
2662 u64 ghcb_scratch_beg, ghcb_scratch_end;
2663 u64 scratch_gpa_beg, scratch_gpa_end;
2664 void *scratch_va;
2665
2666 scratch_gpa_beg = svm->sev_es.sw_scratch;
2667 if (!scratch_gpa_beg) {
2668 pr_err("vmgexit: scratch gpa not provided\n");
2669 goto e_scratch;
2670 }
2671
2672 scratch_gpa_end = scratch_gpa_beg + len;
2673 if (scratch_gpa_end < scratch_gpa_beg) {
2674 pr_err("vmgexit: scratch length (%#llx) not valid for scratch address (%#llx)\n",
2675 len, scratch_gpa_beg);
2676 goto e_scratch;
2677 }
2678
2679 if ((scratch_gpa_beg & PAGE_MASK) == control->ghcb_gpa) {
2680 /* Scratch area begins within GHCB */
2681 ghcb_scratch_beg = control->ghcb_gpa +
2682 offsetof(struct ghcb, shared_buffer);
2683 ghcb_scratch_end = control->ghcb_gpa +
2684 offsetof(struct ghcb, reserved_0xff0);
2685
2686 /*
2687 * If the scratch area begins within the GHCB, it must be
2688 * completely contained in the GHCB shared buffer area.
2689 */
2690 if (scratch_gpa_beg < ghcb_scratch_beg ||
2691 scratch_gpa_end > ghcb_scratch_end) {
2692 pr_err("vmgexit: scratch area is outside of GHCB shared buffer area (%#llx - %#llx)\n",
2693 scratch_gpa_beg, scratch_gpa_end);
2694 goto e_scratch;
2695 }
2696
2697 scratch_va = (void *)svm->sev_es.ghcb;
2698 scratch_va += (scratch_gpa_beg - control->ghcb_gpa);
2699 } else {
2700 /*
2701 * The guest memory must be read into a kernel buffer, so
2702 * limit the size
2703 */
2704 if (len > GHCB_SCRATCH_AREA_LIMIT) {
2705 pr_err("vmgexit: scratch area exceeds KVM limits (%#llx requested, %#llx limit)\n",
2706 len, GHCB_SCRATCH_AREA_LIMIT);
2707 goto e_scratch;
2708 }
2709 scratch_va = kvzalloc(len, GFP_KERNEL_ACCOUNT);
2710 if (!scratch_va)
2711 return -ENOMEM;
2712
2713 if (kvm_read_guest(svm->vcpu.kvm, scratch_gpa_beg, scratch_va, len)) {
2714 /* Unable to copy scratch area from guest */
2715 pr_err("vmgexit: kvm_read_guest for scratch area failed\n");
2716
2717 kvfree(scratch_va);
2718 return -EFAULT;
2719 }
2720
2721 /*
2722 * The scratch area is outside the GHCB. The operation will
2723 * dictate whether the buffer needs to be synced before running
2724 * the vCPU next time (i.e. a read was requested so the data
2725 * must be written back to the guest memory).
2726 */
2727 svm->sev_es.ghcb_sa_sync = sync;
2728 svm->sev_es.ghcb_sa_free = true;
2729 }
2730
2731 svm->sev_es.ghcb_sa = scratch_va;
2732 svm->sev_es.ghcb_sa_len = len;
2733
2734 return 0;
2735
2736 e_scratch:
2737 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2);
2738 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_SCRATCH_AREA);
2739
2740 return 1;
2741 }
2742
set_ghcb_msr_bits(struct vcpu_svm * svm,u64 value,u64 mask,unsigned int pos)2743 static void set_ghcb_msr_bits(struct vcpu_svm *svm, u64 value, u64 mask,
2744 unsigned int pos)
2745 {
2746 svm->vmcb->control.ghcb_gpa &= ~(mask << pos);
2747 svm->vmcb->control.ghcb_gpa |= (value & mask) << pos;
2748 }
2749
get_ghcb_msr_bits(struct vcpu_svm * svm,u64 mask,unsigned int pos)2750 static u64 get_ghcb_msr_bits(struct vcpu_svm *svm, u64 mask, unsigned int pos)
2751 {
2752 return (svm->vmcb->control.ghcb_gpa >> pos) & mask;
2753 }
2754
set_ghcb_msr(struct vcpu_svm * svm,u64 value)2755 static void set_ghcb_msr(struct vcpu_svm *svm, u64 value)
2756 {
2757 svm->vmcb->control.ghcb_gpa = value;
2758 }
2759
sev_handle_vmgexit_msr_protocol(struct vcpu_svm * svm)2760 static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm)
2761 {
2762 struct vmcb_control_area *control = &svm->vmcb->control;
2763 struct kvm_vcpu *vcpu = &svm->vcpu;
2764 u64 ghcb_info;
2765 int ret = 1;
2766
2767 ghcb_info = control->ghcb_gpa & GHCB_MSR_INFO_MASK;
2768
2769 trace_kvm_vmgexit_msr_protocol_enter(svm->vcpu.vcpu_id,
2770 control->ghcb_gpa);
2771
2772 switch (ghcb_info) {
2773 case GHCB_MSR_SEV_INFO_REQ:
2774 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX,
2775 GHCB_VERSION_MIN,
2776 sev_enc_bit));
2777 break;
2778 case GHCB_MSR_CPUID_REQ: {
2779 u64 cpuid_fn, cpuid_reg, cpuid_value;
2780
2781 cpuid_fn = get_ghcb_msr_bits(svm,
2782 GHCB_MSR_CPUID_FUNC_MASK,
2783 GHCB_MSR_CPUID_FUNC_POS);
2784
2785 /* Initialize the registers needed by the CPUID intercept */
2786 vcpu->arch.regs[VCPU_REGS_RAX] = cpuid_fn;
2787 vcpu->arch.regs[VCPU_REGS_RCX] = 0;
2788
2789 ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_CPUID);
2790 if (!ret) {
2791 /* Error, keep GHCB MSR value as-is */
2792 break;
2793 }
2794
2795 cpuid_reg = get_ghcb_msr_bits(svm,
2796 GHCB_MSR_CPUID_REG_MASK,
2797 GHCB_MSR_CPUID_REG_POS);
2798 if (cpuid_reg == 0)
2799 cpuid_value = vcpu->arch.regs[VCPU_REGS_RAX];
2800 else if (cpuid_reg == 1)
2801 cpuid_value = vcpu->arch.regs[VCPU_REGS_RBX];
2802 else if (cpuid_reg == 2)
2803 cpuid_value = vcpu->arch.regs[VCPU_REGS_RCX];
2804 else
2805 cpuid_value = vcpu->arch.regs[VCPU_REGS_RDX];
2806
2807 set_ghcb_msr_bits(svm, cpuid_value,
2808 GHCB_MSR_CPUID_VALUE_MASK,
2809 GHCB_MSR_CPUID_VALUE_POS);
2810
2811 set_ghcb_msr_bits(svm, GHCB_MSR_CPUID_RESP,
2812 GHCB_MSR_INFO_MASK,
2813 GHCB_MSR_INFO_POS);
2814 break;
2815 }
2816 case GHCB_MSR_TERM_REQ: {
2817 u64 reason_set, reason_code;
2818
2819 reason_set = get_ghcb_msr_bits(svm,
2820 GHCB_MSR_TERM_REASON_SET_MASK,
2821 GHCB_MSR_TERM_REASON_SET_POS);
2822 reason_code = get_ghcb_msr_bits(svm,
2823 GHCB_MSR_TERM_REASON_MASK,
2824 GHCB_MSR_TERM_REASON_POS);
2825 pr_info("SEV-ES guest requested termination: %#llx:%#llx\n",
2826 reason_set, reason_code);
2827
2828 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
2829 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_SEV_TERM;
2830 vcpu->run->system_event.ndata = 1;
2831 vcpu->run->system_event.data[0] = control->ghcb_gpa;
2832
2833 return 0;
2834 }
2835 default:
2836 /* Error, keep GHCB MSR value as-is */
2837 break;
2838 }
2839
2840 trace_kvm_vmgexit_msr_protocol_exit(svm->vcpu.vcpu_id,
2841 control->ghcb_gpa, ret);
2842
2843 return ret;
2844 }
2845
sev_handle_vmgexit(struct kvm_vcpu * vcpu)2846 int sev_handle_vmgexit(struct kvm_vcpu *vcpu)
2847 {
2848 struct vcpu_svm *svm = to_svm(vcpu);
2849 struct vmcb_control_area *control = &svm->vmcb->control;
2850 u64 ghcb_gpa, exit_code;
2851 int ret;
2852
2853 /* Validate the GHCB */
2854 ghcb_gpa = control->ghcb_gpa;
2855 if (ghcb_gpa & GHCB_MSR_INFO_MASK)
2856 return sev_handle_vmgexit_msr_protocol(svm);
2857
2858 if (!ghcb_gpa) {
2859 vcpu_unimpl(vcpu, "vmgexit: GHCB gpa is not set\n");
2860
2861 /* Without a GHCB, just return right back to the guest */
2862 return 1;
2863 }
2864
2865 if (kvm_vcpu_map(vcpu, ghcb_gpa >> PAGE_SHIFT, &svm->sev_es.ghcb_map)) {
2866 /* Unable to map GHCB from guest */
2867 vcpu_unimpl(vcpu, "vmgexit: error mapping GHCB [%#llx] from guest\n",
2868 ghcb_gpa);
2869
2870 /* Without a GHCB, just return right back to the guest */
2871 return 1;
2872 }
2873
2874 svm->sev_es.ghcb = svm->sev_es.ghcb_map.hva;
2875
2876 trace_kvm_vmgexit_enter(vcpu->vcpu_id, svm->sev_es.ghcb);
2877
2878 sev_es_sync_from_ghcb(svm);
2879 ret = sev_es_validate_vmgexit(svm);
2880 if (ret)
2881 return ret;
2882
2883 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 0);
2884 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 0);
2885
2886 exit_code = kvm_ghcb_get_sw_exit_code(control);
2887 switch (exit_code) {
2888 case SVM_VMGEXIT_MMIO_READ:
2889 ret = setup_vmgexit_scratch(svm, true, control->exit_info_2);
2890 if (ret)
2891 break;
2892
2893 ret = kvm_sev_es_mmio_read(vcpu,
2894 control->exit_info_1,
2895 control->exit_info_2,
2896 svm->sev_es.ghcb_sa);
2897 break;
2898 case SVM_VMGEXIT_MMIO_WRITE:
2899 ret = setup_vmgexit_scratch(svm, false, control->exit_info_2);
2900 if (ret)
2901 break;
2902
2903 ret = kvm_sev_es_mmio_write(vcpu,
2904 control->exit_info_1,
2905 control->exit_info_2,
2906 svm->sev_es.ghcb_sa);
2907 break;
2908 case SVM_VMGEXIT_NMI_COMPLETE:
2909 ++vcpu->stat.nmi_window_exits;
2910 svm->nmi_masked = false;
2911 kvm_make_request(KVM_REQ_EVENT, vcpu);
2912 ret = 1;
2913 break;
2914 case SVM_VMGEXIT_AP_HLT_LOOP:
2915 ret = kvm_emulate_ap_reset_hold(vcpu);
2916 break;
2917 case SVM_VMGEXIT_AP_JUMP_TABLE: {
2918 struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info;
2919
2920 switch (control->exit_info_1) {
2921 case 0:
2922 /* Set AP jump table address */
2923 sev->ap_jump_table = control->exit_info_2;
2924 break;
2925 case 1:
2926 /* Get AP jump table address */
2927 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, sev->ap_jump_table);
2928 break;
2929 default:
2930 pr_err("svm: vmgexit: unsupported AP jump table request - exit_info_1=%#llx\n",
2931 control->exit_info_1);
2932 ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, 2);
2933 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_INPUT);
2934 }
2935
2936 ret = 1;
2937 break;
2938 }
2939 case SVM_VMGEXIT_UNSUPPORTED_EVENT:
2940 vcpu_unimpl(vcpu,
2941 "vmgexit: unsupported event - exit_info_1=%#llx, exit_info_2=%#llx\n",
2942 control->exit_info_1, control->exit_info_2);
2943 ret = -EINVAL;
2944 break;
2945 default:
2946 ret = svm_invoke_exit_handler(vcpu, exit_code);
2947 }
2948
2949 return ret;
2950 }
2951
sev_es_string_io(struct vcpu_svm * svm,int size,unsigned int port,int in)2952 int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in)
2953 {
2954 int count;
2955 int bytes;
2956 int r;
2957
2958 if (svm->vmcb->control.exit_info_2 > INT_MAX)
2959 return -EINVAL;
2960
2961 count = svm->vmcb->control.exit_info_2;
2962 if (unlikely(check_mul_overflow(count, size, &bytes)))
2963 return -EINVAL;
2964
2965 r = setup_vmgexit_scratch(svm, in, bytes);
2966 if (r)
2967 return r;
2968
2969 return kvm_sev_es_string_io(&svm->vcpu, size, port, svm->sev_es.ghcb_sa,
2970 count, in);
2971 }
2972
sev_es_vcpu_after_set_cpuid(struct vcpu_svm * svm)2973 static void sev_es_vcpu_after_set_cpuid(struct vcpu_svm *svm)
2974 {
2975 struct kvm_vcpu *vcpu = &svm->vcpu;
2976
2977 if (boot_cpu_has(X86_FEATURE_V_TSC_AUX)) {
2978 bool v_tsc_aux = guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) ||
2979 guest_cpuid_has(vcpu, X86_FEATURE_RDPID);
2980
2981 set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, v_tsc_aux, v_tsc_aux);
2982 }
2983
2984 /*
2985 * For SEV-ES, accesses to MSR_IA32_XSS should not be intercepted if
2986 * the host/guest supports its use.
2987 *
2988 * guest_can_use() checks a number of requirements on the host/guest to
2989 * ensure that MSR_IA32_XSS is available, but it might report true even
2990 * if X86_FEATURE_XSAVES isn't configured in the guest to ensure host
2991 * MSR_IA32_XSS is always properly restored. For SEV-ES, it is better
2992 * to further check that the guest CPUID actually supports
2993 * X86_FEATURE_XSAVES so that accesses to MSR_IA32_XSS by misbehaved
2994 * guests will still get intercepted and caught in the normal
2995 * kvm_emulate_rdmsr()/kvm_emulated_wrmsr() paths.
2996 */
2997 if (guest_can_use(vcpu, X86_FEATURE_XSAVES) &&
2998 guest_cpuid_has(vcpu, X86_FEATURE_XSAVES))
2999 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_XSS, 1, 1);
3000 else
3001 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_XSS, 0, 0);
3002 }
3003
sev_vcpu_after_set_cpuid(struct vcpu_svm * svm)3004 void sev_vcpu_after_set_cpuid(struct vcpu_svm *svm)
3005 {
3006 struct kvm_vcpu *vcpu = &svm->vcpu;
3007 struct kvm_cpuid_entry2 *best;
3008
3009 /* For sev guests, the memory encryption bit is not reserved in CR3. */
3010 best = kvm_find_cpuid_entry(vcpu, 0x8000001F);
3011 if (best)
3012 vcpu->arch.reserved_gpa_bits &= ~(1UL << (best->ebx & 0x3f));
3013
3014 if (sev_es_guest(svm->vcpu.kvm))
3015 sev_es_vcpu_after_set_cpuid(svm);
3016 }
3017
sev_es_init_vmcb(struct vcpu_svm * svm)3018 static void sev_es_init_vmcb(struct vcpu_svm *svm)
3019 {
3020 struct vmcb *vmcb = svm->vmcb01.ptr;
3021 struct kvm_vcpu *vcpu = &svm->vcpu;
3022
3023 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ES_ENABLE;
3024 svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK;
3025
3026 /*
3027 * An SEV-ES guest requires a VMSA area that is a separate from the
3028 * VMCB page. Do not include the encryption mask on the VMSA physical
3029 * address since hardware will access it using the guest key. Note,
3030 * the VMSA will be NULL if this vCPU is the destination for intrahost
3031 * migration, and will be copied later.
3032 */
3033 if (svm->sev_es.vmsa)
3034 svm->vmcb->control.vmsa_pa = __pa(svm->sev_es.vmsa);
3035
3036 /* Can't intercept CR register access, HV can't modify CR registers */
3037 svm_clr_intercept(svm, INTERCEPT_CR0_READ);
3038 svm_clr_intercept(svm, INTERCEPT_CR4_READ);
3039 svm_clr_intercept(svm, INTERCEPT_CR8_READ);
3040 svm_clr_intercept(svm, INTERCEPT_CR0_WRITE);
3041 svm_clr_intercept(svm, INTERCEPT_CR4_WRITE);
3042 svm_clr_intercept(svm, INTERCEPT_CR8_WRITE);
3043
3044 svm_clr_intercept(svm, INTERCEPT_SELECTIVE_CR0);
3045
3046 /* Track EFER/CR register changes */
3047 svm_set_intercept(svm, TRAP_EFER_WRITE);
3048 svm_set_intercept(svm, TRAP_CR0_WRITE);
3049 svm_set_intercept(svm, TRAP_CR4_WRITE);
3050 svm_set_intercept(svm, TRAP_CR8_WRITE);
3051
3052 vmcb->control.intercepts[INTERCEPT_DR] = 0;
3053 if (!sev_es_debug_swap_enabled) {
3054 vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_READ);
3055 vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_WRITE);
3056 recalc_intercepts(svm);
3057 } else {
3058 /*
3059 * Disable #DB intercept iff DebugSwap is enabled. KVM doesn't
3060 * allow debugging SEV-ES guests, and enables DebugSwap iff
3061 * NO_NESTED_DATA_BP is supported, so there's no reason to
3062 * intercept #DB when DebugSwap is enabled. For simplicity
3063 * with respect to guest debug, intercept #DB for other VMs
3064 * even if NO_NESTED_DATA_BP is supported, i.e. even if the
3065 * guest can't DoS the CPU with infinite #DB vectoring.
3066 */
3067 clr_exception_intercept(svm, DB_VECTOR);
3068 }
3069
3070 /* Can't intercept XSETBV, HV can't modify XCR0 directly */
3071 svm_clr_intercept(svm, INTERCEPT_XSETBV);
3072
3073 /* Clear intercepts on selected MSRs */
3074 set_msr_interception(vcpu, svm->msrpm, MSR_EFER, 1, 1);
3075 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_CR_PAT, 1, 1);
3076 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1);
3077 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1);
3078 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 1, 1);
3079 set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1);
3080 }
3081
sev_init_vmcb(struct vcpu_svm * svm)3082 void sev_init_vmcb(struct vcpu_svm *svm)
3083 {
3084 svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ENABLE;
3085 clr_exception_intercept(svm, UD_VECTOR);
3086
3087 /*
3088 * Don't intercept #GP for SEV guests, e.g. for the VMware backdoor, as
3089 * KVM can't decrypt guest memory to decode the faulting instruction.
3090 */
3091 clr_exception_intercept(svm, GP_VECTOR);
3092
3093 if (sev_es_guest(svm->vcpu.kvm))
3094 sev_es_init_vmcb(svm);
3095 }
3096
sev_es_vcpu_reset(struct vcpu_svm * svm)3097 void sev_es_vcpu_reset(struct vcpu_svm *svm)
3098 {
3099 /*
3100 * Set the GHCB MSR value as per the GHCB specification when emulating
3101 * vCPU RESET for an SEV-ES guest.
3102 */
3103 set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX,
3104 GHCB_VERSION_MIN,
3105 sev_enc_bit));
3106 }
3107
sev_es_prepare_switch_to_guest(struct sev_es_save_area * hostsa)3108 void sev_es_prepare_switch_to_guest(struct sev_es_save_area *hostsa)
3109 {
3110 /*
3111 * All host state for SEV-ES guests is categorized into three swap types
3112 * based on how it is handled by hardware during a world switch:
3113 *
3114 * A: VMRUN: Host state saved in host save area
3115 * VMEXIT: Host state loaded from host save area
3116 *
3117 * B: VMRUN: Host state _NOT_ saved in host save area
3118 * VMEXIT: Host state loaded from host save area
3119 *
3120 * C: VMRUN: Host state _NOT_ saved in host save area
3121 * VMEXIT: Host state initialized to default(reset) values
3122 *
3123 * Manually save type-B state, i.e. state that is loaded by VMEXIT but
3124 * isn't saved by VMRUN, that isn't already saved by VMSAVE (performed
3125 * by common SVM code).
3126 */
3127 hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
3128 hostsa->pkru = read_pkru();
3129 hostsa->xss = host_xss;
3130
3131 /*
3132 * If DebugSwap is enabled, debug registers are loaded but NOT saved by
3133 * the CPU (Type-B). If DebugSwap is disabled/unsupported, the CPU both
3134 * saves and loads debug registers (Type-A).
3135 */
3136 if (sev_es_debug_swap_enabled) {
3137 hostsa->dr0 = native_get_debugreg(0);
3138 hostsa->dr1 = native_get_debugreg(1);
3139 hostsa->dr2 = native_get_debugreg(2);
3140 hostsa->dr3 = native_get_debugreg(3);
3141 hostsa->dr0_addr_mask = amd_get_dr_addr_mask(0);
3142 hostsa->dr1_addr_mask = amd_get_dr_addr_mask(1);
3143 hostsa->dr2_addr_mask = amd_get_dr_addr_mask(2);
3144 hostsa->dr3_addr_mask = amd_get_dr_addr_mask(3);
3145 }
3146 }
3147
sev_vcpu_deliver_sipi_vector(struct kvm_vcpu * vcpu,u8 vector)3148 void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector)
3149 {
3150 struct vcpu_svm *svm = to_svm(vcpu);
3151
3152 /* First SIPI: Use the values as initially set by the VMM */
3153 if (!svm->sev_es.received_first_sipi) {
3154 svm->sev_es.received_first_sipi = true;
3155 return;
3156 }
3157
3158 /*
3159 * Subsequent SIPI: Return from an AP Reset Hold VMGEXIT, where
3160 * the guest will set the CS and RIP. Set SW_EXIT_INFO_2 to a
3161 * non-zero value.
3162 */
3163 if (!svm->sev_es.ghcb)
3164 return;
3165
3166 ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 1);
3167 }
3168