xref: /kvm-unit-tests/x86/pcid.c (revision a299895b7abb54e7ba6bb4108f202acbb484ac65)
1 /* Basic PCID & INVPCID functionality test */
2 
3 #include "libcflat.h"
4 #include "processor.h"
5 #include "desc.h"
6 
7 struct invpcid_desc {
8     unsigned long pcid : 12;
9     unsigned long rsv  : 52;
10     unsigned long addr : 64;
11 };
12 
13 static int write_cr0_checking(unsigned long val)
14 {
15     asm volatile(ASM_TRY("1f")
16                  "mov %0, %%cr0\n\t"
17                  "1:": : "r" (val));
18     return exception_vector();
19 }
20 
21 static int invpcid_checking(unsigned long type, void *desc)
22 {
23     asm volatile (ASM_TRY("1f")
24                   ".byte 0x66,0x0f,0x38,0x82,0x18 \n\t" /* invpcid (%rax), %rbx */
25                   "1:" : : "a" (desc), "b" (type));
26     return exception_vector();
27 }
28 
29 static void test_cpuid_consistency(int pcid_enabled, int invpcid_enabled)
30 {
31     int passed = !(!pcid_enabled && invpcid_enabled);
32     report(passed, "CPUID consistency");
33 }
34 
35 static void test_pcid_enabled(void)
36 {
37     int passed = 0;
38     ulong cr0 = read_cr0(), cr3 = read_cr3(), cr4 = read_cr4();
39 
40     /* try setting CR4.PCIDE, no exception expected */
41     if (write_cr4_checking(cr4 | X86_CR4_PCIDE) != 0)
42         goto report;
43 
44     /* try clearing CR0.PG when CR4.PCIDE=1, #GP expected */
45     if (write_cr0_checking(cr0 & ~X86_CR0_PG) != GP_VECTOR)
46         goto report;
47 
48     write_cr4(cr4);
49 
50     /* try setting CR4.PCIDE when CR3[11:0] != 0 , #GP expected */
51     write_cr3(cr3 | 0x001);
52     if (write_cr4_checking(cr4 | X86_CR4_PCIDE) != GP_VECTOR)
53         goto report;
54     write_cr3(cr3);
55 
56     passed = 1;
57 
58 report:
59     report(passed, "Test on PCID when enabled");
60 }
61 
62 static void test_pcid_disabled(void)
63 {
64     int passed = 0;
65     ulong cr4 = read_cr4();
66 
67     /* try setting CR4.PCIDE, #GP expected */
68     if (write_cr4_checking(cr4 | X86_CR4_PCIDE) != GP_VECTOR)
69         goto report;
70 
71     passed = 1;
72 
73 report:
74     report(passed, "Test on PCID when disabled");
75 }
76 
77 static void test_invpcid_enabled(void)
78 {
79     int passed = 0;
80     ulong cr4 = read_cr4();
81     struct invpcid_desc desc;
82     desc.rsv = 0;
83 
84     /* try executing invpcid when CR4.PCIDE=0, desc.pcid=0 and type=1
85      * no exception expected
86      */
87     desc.pcid = 0;
88     if (invpcid_checking(1, &desc) != 0)
89         goto report;
90 
91     /* try executing invpcid when CR4.PCIDE=0, desc.pcid=1 and type=1
92      * #GP expected
93      */
94     desc.pcid = 1;
95     if (invpcid_checking(1, &desc) != GP_VECTOR)
96         goto report;
97 
98     if (write_cr4_checking(cr4 | X86_CR4_PCIDE) != 0)
99         goto report;
100 
101     /* try executing invpcid when CR4.PCIDE=1
102      * no exception expected
103      */
104     desc.pcid = 10;
105     if (invpcid_checking(2, &desc) != 0)
106         goto report;
107 
108     passed = 1;
109 
110 report:
111     report(passed, "Test on INVPCID when enabled");
112 }
113 
114 static void test_invpcid_disabled(void)
115 {
116     int passed = 0;
117     struct invpcid_desc desc;
118 
119     /* try executing invpcid, #UD expected */
120     if (invpcid_checking(2, &desc) != UD_VECTOR)
121         goto report;
122 
123     passed = 1;
124 
125 report:
126     report(passed, "Test on INVPCID when disabled");
127 }
128 
129 int main(int ac, char **av)
130 {
131     int pcid_enabled = 0, invpcid_enabled = 0;
132 
133     setup_idt();
134 
135     if (this_cpu_has(X86_FEATURE_PCID))
136         pcid_enabled = 1;
137     if (this_cpu_has(X86_FEATURE_INVPCID))
138         invpcid_enabled = 1;
139 
140     test_cpuid_consistency(pcid_enabled, invpcid_enabled);
141 
142     if (pcid_enabled)
143         test_pcid_enabled();
144     else
145         test_pcid_disabled();
146 
147     if (invpcid_enabled)
148         test_invpcid_enabled();
149     else
150         test_invpcid_disabled();
151 
152     return report_summary();
153 }
154