Changes in Makefile

c8db08110cbeff12a1f3990a31730936b092f62b - Merge tag 'vfs-7.1-rc1.xattr' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Mon, 13 Apr 2026 17:10:28 +0000

Merge tag 'vfs-7.1-rc1.xattr' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfsPull vfs xattr updates from Christian Brauner: "This reworks the simple_xattr infrastructure and adds support for user.* extended attributes on sockets. The simple_xattr subsystem currently uses an rbtree protected by a reader-writer spinlock. This series replaces the rbtree with an rhashtable giving O(1) average-case lookup with RCU-based lockless reads. This sped up concurrent access patterns on tmpfs quite a bit and it's an overall easy enough conversion to do and gets rid or rwlock_t. The conversion is done incrementally: a new rhashtable path is added alongside the existing rbtree, consumers are migrated one at a time (shmem, kernfs, pidfs), and then the rbtree code is removed. All three consumers switch from embedded structs to pointer-based lazy allocation so the rhashtable overhead is only paid for inodes that actually use xattrs. With this infrastructure in place the series adds support for user.* xattrs on sockets. Path-based AF_UNIX sockets inherit xattr support from the underlying filesystem (e.g. tmpfs) but sockets in sockfs - that is everything created via socket() including abstract namespace AF_UNIX sockets - had no xattr support at all. The xattr_permission() checks are reworked to allow user.* xattrs on S_IFSOCK inodes. Sockfs sockets get per-inode limits of 128 xattrs and 128KB total value size matching the limits already in use for kernfs. The practical motivation comes from several directions. systemd and GNOME are expanding their use of Varlink as an IPC mechanism. For D-Bus there are tools like dbus-monitor that can observe IPC traffic across the system but this only works because D-Bus has a central broker. For Varlink there is no broker and there is currently no way to identify which sockets speak Varlink. With user.* xattrs on sockets a service can label its socket with the IPC protocol it speaks (e.g., user.varlink=1) and an eBPF program can then selectively capture traffic on those sockets. Enumerating bound sockets via netlink combined with these xattr labels gives a way to discover all Varlink IPC entrypoints for debugging and introspection. Similarly, systemd-journald wants to use xattrs on the /dev/log socket for protocol negotiation to indicate whether RFC 5424 structured syslog is supported or whether only the legacy RFC 3164 format should be used. In containers these labels are particularly useful as high-privilege or more complicated solutions for socket identification aren't available. The series comes with comprehensive selftests covering path-based AF_UNIX sockets, sockfs socket operations, per-inode limit enforcement, and xattr operations across multiple address families (AF_INET, AF_INET6, AF_NETLINK, AF_PACKET)"* tag 'vfs-7.1-rc1.xattr' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: selftests/xattr: test xattrs on various socket families selftests/xattr: sockfs socket xattr tests selftests/xattr: path-based AF_UNIX socket xattr tests xattr: support extended attributes on sockets xattr,net: support limited amount of extended attributes on sockfs sockets xattr: move user limits for xattrs to generic infra xattr: switch xattr_permission() to switch statement xattr: add xattr_permission_error() xattr: remove rbtree-based simple_xattr infrastructure pidfs: adapt to rhashtable-based simple_xattrs kernfs: adapt to rhashtable-based simple_xattrs with lazy allocation shmem: adapt to rhashtable-based simple_xattrs with lazy allocation xattr: add rhashtable-based simple_xattr infrastructure xattr: add rcu_head and rhash_head to struct simple_xattr List of files: /linux/tools/testing/selftests/filesystems/xattr/Makefile

98779186aa0b3367489a87c6d8bc0911f577444e - Merge patch series "xattr: rework simple xattrs and support user.* xattrs on sockets"

Mon, 23 Feb 2026 12:06:04 +0000

Merge patch series "xattr: rework simple xattrs and support user.* xattrs on sockets"Christian Brauner says:This reworks the simple_xattr infrastructure and adds support foruser.* extended attributes on sockets.The simple_xattr subsystem currently uses an rbtree protected by areader-writer spinlock. This series replaces the rbtree with anrhashtable giving O(1) average-case lookup with RCU-based locklessreads. This sped up concurrent access patterns on tmpfs quite a bit andit's an overall easy enough conversion to do and gets rid or rwlock_t.The conversion is done incrementally: a new rhashtable path is addedalongside the existing rbtree, consumers are migrated one at a time(shmem, kernfs, pidfs), and then the rbtree code is removed. All threeconsumers switch from embedded structs to pointer-based lazy allocationso the rhashtable overhead is only paid for inodes that actually usexattrs.With this infrastructure in place the series adds support for user.*xattrs on sockets. Path-based AF_UNIX sockets inherit xattr supportfrom the underlying filesystem (e.g. tmpfs) but sockets in sockfs -that is everything created via socket() including abstract namespaceAF_UNIX sockets - had no xattr support at all.The xattr_permission() checks are reworked to allow user.* xattrs onS_IFSOCK inodes. Sockfs sockets get per-inode limits of 128 xattrs and128KB total value size matching the limits already in use for kernfs.The practical motivation comes from several directions. systemd andGNOME are expanding their use of Varlink as an IPC mechanism. For D-Busthere are tools like dbus-monitor that can observe IPC traffic acrossthe system but this only works because D-Bus has a central broker. ForVarlink there is no broker and there is currently no way to identifywhich sockets speak Varlink. With user.* xattrs on sockets a servicecan label its socket with the IPC protocol it speaks (e.g.,user.varlink=1) and an eBPF program can then selectively capturetraffic on those sockets. Enumerating bound sockets via netlink combinedwith these xattr labels gives a way to discover all Varlink IPCentrypoints for debugging and introspection.Similarly, systemd-journald wants to use xattrs on the /dev/log socketfor protocol negotiation to indicate whether RFC 5424 structured syslogis supported or whether only the legacy RFC 3164 format should be used.In containers these labels are particularly useful as high-privilege ormore complicated solutions for socket identification aren't available.The series comes with comprehensive selftests covering path-basedAF_UNIX sockets, sockfs socket operations, per-inode limit enforcement,and xattr operations across multiple address families (AF_INET,AF_INET6, AF_NETLINK, AF_PACKET).* patches from https://patch.msgid.link/20260216-work-xattr-socket-v1-0-c2efa4f74cb7@kernel.org: selftests/xattr: test xattrs on various socket families selftests/xattr: sockfs socket xattr tests selftests/xattr: path-based AF_UNIX socket xattr tests xattr: support extended attributes on sockets xattr,net: support limited amount of extended attributes on sockfs sockets xattr: move user limits for xattrs to generic infra xattr: switch xattr_permission() to switch statement xattr: add xattr_permission_error() xattr: remove rbtree-based simple_xattr infrastructure pidfs: adapt to rhashtable-based simple_xattrs kernfs: adapt to rhashtable-based simple_xattrs with lazy allocation shmem: adapt to rhashtable-based simple_xattrs with lazy allocation xattr: add rhashtable-based simple_xattr infrastructure xattr: add rcu_head and rhash_head to struct simple_xattrLink: https://patch.msgid.link/20260216-work-xattr-socket-v1-0-c2efa4f74cb7@kernel.orgSigned-off-by: Christian Brauner List of files: /linux/tools/testing/selftests/filesystems/xattr/Makefile

0f1f4e4e1503e605f2189bfa10290d7b8920187c - selftests/xattr: test xattrs on various socket families

Mon, 16 Feb 2026 13:32:10 +0000

selftests/xattr: test xattrs on various socket familiesTest user.* xattr operations on sockets from different address families:AF_INET, AF_INET6, AF_NETLINK, and AF_PACKET. All socket types usesockfs for their inodes, so user.* xattrs should work regardless ofaddress family.Each fixture creates a socket (no bind needed) and verifies the fullfsetxattr/fgetxattr/flistxattr/fremovexattr cycle. AF_INET6 skips ifnot supported; AF_PACKET skips if CAP_NET_RAW is unavailable.Also tests abstract namespace AF_UNIX sockets, which live in sockfs(not on a filesystem) and should support user.* xattrs.Link: https://patch.msgid.link/20260216-work-xattr-socket-v1-14-c2efa4f74cb7@kernel.orgAcked-by: Darrick J. Wong Reviewed-by: Jan Kara Signed-off-by: Christian Brauner List of files: /linux/tools/testing/selftests/filesystems/xattr/Makefile

0e75aea0b52dc8918fed4db40b035b2ef2cded40 - selftests/xattr: sockfs socket xattr tests

Mon, 16 Feb 2026 13:32:09 +0000

selftests/xattr: sockfs socket xattr testsTest user.* extended attribute operations on sockfs sockets. Socketscreated via socket() have their inodes in sockfs, which now supportsuser.* xattrs with per-inode limits.Tests fsetxattr/fgetxattr/flistxattr/fremovexattr operations includingset/get, listing (verifies system.sockprotoname presence), remove,update, XATTR_CREATE/XATTR_REPLACE flags, empty values, size queries,and buffer-too-small errors.Also tests per-inode limit enforcement: maximum 128 xattrs, maximum128KB total value size, limit recovery after removal, and independentlimits across different sockets.Link: https://patch.msgid.link/20260216-work-xattr-socket-v1-13-c2efa4f74cb7@kernel.orgAcked-by: Darrick J. Wong Reviewed-by: Jan Kara Signed-off-by: Christian Brauner List of files: /linux/tools/testing/selftests/filesystems/xattr/Makefile

7e28fef5d4db3a5e61cfcd4b09313933d16c0430 - selftests/xattr: path-based AF_UNIX socket xattr tests

Mon, 16 Feb 2026 13:32:08 +0000

selftests/xattr: path-based AF_UNIX socket xattr testsTest user.* extended attribute operations on path-based Unix domainsockets (SOCK_STREAM, SOCK_DGRAM, SOCK_SEQPACKET). Path-based socketsare bound to a filesystem path and their inodes live on the underlyingfilesystem (e.g. tmpfs).Covers set/get/list/remove, persistence, XATTR_CREATE/XATTR_REPLACEflags, empty values, size queries, buffer-too-small errors, O_PATH fdoperations, and trusted.* xattr handling.Link: https://patch.msgid.link/20260216-work-xattr-socket-v1-12-c2efa4f74cb7@kernel.orgAcked-by: Darrick J. Wong Reviewed-by: Jan Kara Signed-off-by: Christian Brauner List of files: /linux/tools/testing/selftests/filesystems/xattr/Makefile