The DP83640 has a fixed number of PTP pins, and its pin configuration
has the same lifetime as the per-bus clock. Allocating the configuration
separately adds an allocation failure path and requires a separate free.
Embed the pin configuration in struct dp83640_clock and point the PTP
clock information at the embedded array. This changes only the storage;
the pin functions remain configurable at runtime. It also allows all
per-bus clock storage to be managed as one allocation.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn>
Link: https://patch.msgid.link/20260811151345.73582-3-xuanqiang.luo@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The PHY package API provides private data shared by all PHYs in a
package. Drivers are responsible for synchronizing access to this data,
but the API does not provide a lock for that purpose.
Add phy_package_lock() and phy_package_unlock() for drivers to serialize
access to package-private data, including its initialization.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn>
Link: https://patch.msgid.link/20260811151345.73582-2-xuanqiang.luo@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
- Fix NULL pointer dereference when matching unloaded module wildcard event
The set_event can take events for modules that have not been loaded
yet. This is done by writing '<event>:mod:<module>'.
If '<event>' is not added, then it means to add all events in <module>.
This wildcard is represented by a NULL pointer. If one were to try to
remove the same module item with a named event it would cause a NULL
pointer dereference when comparing the NULL with the name in strcmp().
echo ':mod:kvm' > /sys/kernel/tracing/set_event
echo '!kvm_ack_irq:mod:kvm' >> /sys/kernel/tracing/set_event
The above will do a strcmp("kvm_ack_irq", NULL) and crash the kernel.
Test for NULL (wildcard) before doing the strcmp().
- Fix event data field race in loading two modules at the same time
When a module loads, its trace events get registered. The fields
of the events are also dynamically created and added to the events
fields list. It also will call a function that will look at all the
events for updates that need to be done. If two modules load at the
same time, the one that scans all events and their fields may read
the one being added as the scan doesn't take the event_mutex.
This may cause a data race.
Have the scan take the event_mutex to prevent the race.
-----BEGIN PGP SIGNATURE-----
iIoEABYKADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCan438BQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qq6EAPwNoL0MQ5Yk+rRuWIwDj33FFd3Skwe6
DfqVdxVEzCDdzAEArW2usswnZRlOCZddZPUCVj0MWdNz2sVin3p/j0Qklgg=
=W3ej
-----END PGP SIGNATURE-----
Merge tag 'trace-v7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
- Fix NULL pointer dereference when matching unloaded module wildcard
event
The set_event can take events for modules that have not been loaded
yet. This is done by writing '<event>:mod:<module>'.
If '<event>' is not added, then it means to add all events in
<module>. This wildcard is represented by a NULL pointer. If one were
to try to remove the same module item with a named event it would
cause a NULL pointer dereference when comparing the NULL with the
name in strcmp().
echo ':mod:kvm' > /sys/kernel/tracing/set_event
echo '!kvm_ack_irq:mod:kvm' >> /sys/kernel/tracing/set_event
The above will do a strcmp("kvm_ack_irq", NULL) and crash the kernel.
Test for NULL (wildcard) before doing the strcmp().
- Fix event data field race in loading two modules at the same time
When a module loads, its trace events get registered. The fields of
the events are also dynamically created and added to the events
fields list. It also will call a function that will look at all the
events for updates that need to be done. If two modules load at the
same time, the one that scans all events and their fields may read
the one being added as the scan doesn't take the event_mutex. This
may cause a data race.
Have the scan take the event_mutex to prevent the race.
* tag 'trace-v7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Fix race between update_event_fields and, event_define_fields
tracing: Fix NULL pointer dereference in module event cache removal
Eduard Zingerman says:
====================
selftests/bpf: fix for veristat file/prog filters processing
At the moment veristat filtering behaves unexpectedly for the
following filter expression:
-f !file/prog
The expression rejects all programs with name 'prog', and all programs
in a file with name 'file'. Fix the expression to exclude only a
program 'prog' from a file 'file', also add a set of tests to exercise
filtering logic.
Changelog:
v1 -> v2:
- added fixes tag for patch #1 (bot+bpf-ci);
- extended test cases for '!*foo*' and '*foo*' filters in patch #2
(bot+bpf-ci);
- added patch #3, replacing direct read() calls with calls to
read_output(), guaranteeing input buffer null termination
(bot+bpf-ci).
v1: https://lore.kernel.org/bpf/20260811-veristat-filter-fix-v1-0-b5b43c431550@gmail.com/
---
====================
Link: https://patch.msgid.link/20260811-veristat-filter-fix-v2-0-6c234c4cd6ef@gmail.com
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
In veristat tests replace direct read() calls with calls to
read_output() utility function, which:
- guarantees that the input buffer is zero terminated;
- asserts that read operation succeeded.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260811-veristat-filter-fix-v2-3-6c234c4cd6ef@gmail.com
Test cases for veristat file/prog name filtering logic.
Check various formulations for any (*foo*), file (*foo*/),
prog (/bar) and file/prog (*foo*/bar) filters, alongside
erroneous filters and mixed allow/deny filter expressions.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260811-veristat-filter-fix-v2-2-6c234c4cd6ef@gmail.com
It's customary for NOKPROBE_SYMBOL() macro usage to appear immediately
after a function's final closing brace, but checkpatch doesn't know that
yet. As a result, checkpatch --strict incorrectly flags this common
kernel pattern, e.g.,
CHECK: Please use a blank line after function/struct/union/enum declarations
33: FILE: arch/riscv/kernel/traps.c:273:
}
+NOKPROBE_SYMBOL(probe_single_step_handler);
Fix by adding NOKPROBE_SYMBOL to the whitelist of patterns that are
cleared to appear immediately after functions.
Link: https://lore.kernel.org/130be7db-6098-86a4-60fe-0c1a5d9e30ba@kernel.org
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Acked-by: Joe Perches <joe@perches.com>
Cc: Nam Cao <namcao@linutronix.de>
Cc: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If a negative offset is read off disk (for example the offset into the
decompressed fragment block), this will cause squashfs_copy_data() to
perform an out of bounds access.
Fix by checking if offset is negative, and returning 0. This matches
existing behaviour where an offset beyond the block returns 0 bytes
copied.
To trigger this out of bounds access requires a crafted Squashfs
filesystem and CAP_SYS_ADMIN to mount it. Unprivileged users will not be
able to mount such a filesystem, but once mounted, an unprivileged user
can trigger the out of bounds access by reading the crafted file with the
negative offset.
Link: https://lore.kernel.org/20260807162951.672510-1-phillip@squashfs.org.uk
Fixes: f400e12656 ("Squashfs: cache operations")
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reported-by: Yuejie Shi <syjcnss@gmail.com>
Closes: https://lore.kernel.org/all/20260803032735.81785-1-syjcnss@gmail.com/
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The check that prevents userspace from sending siginfo with si_code values
reserved to the kernel is duplicated across do_rt_sigqueueinfo(),
do_rt_tgsigqueueinfo() and do_pidfd_send_signal(). Move the check into a
helper so the rule lives in one place.
Link: https://lore.kernel.org/20260806133013.4341-1-include@grrlz.net
Signed-off-by: Bradley Morgan <include@grrlz.net>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In ocfs2_dir_foreach_blk_el(), the directory cookie position is
rebuilt with
ctx->pos = (ctx->pos & ~(sb->s_blocksize - 1)) | offset;
`ctx->pos` is loff_t (signed 64-bit), while `sb->s_blocksize` is
unsigned long. On 32-bit kernels unsigned long is 32-bit, so the mask
~(sb->s_blocksize - 1)
is computed as a 32-bit unsigned value (e.g. 0xfffff000 for a 4 KiB
block size). In the AND expression with the 64-bit `ctx->pos`, that
unsigned operand is zero-extended to 64 bits per the usual arithmetic
conversions, yielding 0x00000000fffff000. The high 32 bits of
`ctx->pos` are silently cleared, even though directory size is
allowed to exceed 4 GiB.
When readdir() crosses the 4 GiB boundary on a 32-bit kernel the
position is reset back into the first 4 GiB block, making the
re-validation path re-enumerate already-returned dirents indefinitely.
This is ocfs2_dir_foreach_blk_el(), the extent-list readdir path taken
for all non-inline directories, so a directory large enough to cross
4 GiB reaches it.
This is the same class of bug that commit 3dce5bb82c ("exfat: Fix
bitwise operation having different size") fixed in exfat, and the
fix mirrors the equivalent ext4 fix in this series. Cast the operand
to loff_t so the mask is 64-bit before the AND:
ctx->pos = (ctx->pos & ~((loff_t)sb->s_blocksize - 1)) | offset;
64-bit kernels are unaffected.
Link: https://lore.kernel.org/20260806022044.167962-3-zhanxusheng@xiaomi.com
Fixes: ccd979bdbc ("[PATCH] OCFS2: The Second Oracle Cluster Filesystem")
Signed-off-by: Zhan Xusheng <zhanxusheng@xiaomi.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Cc: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: "zhangyi (F)" <yi.zhang@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When reclaiming a suballocator block group, first reduce the on-disk
cluster count by cl_cpg. The current code then subtracts that new count
(fe->i_clusters) from the old cached count
(OCFS2_I(alloc_inode)->ip_clusters).
For an allocator with N block groups, that leaves the cache at
N * cl_cpg - (N * cl_cpg - cl_cpg) = cl_cpg
i.e. ip_clusters -= (fe->i_clusters - cl_cpg) leaves ip_clusters equal to
cl_cpg regardless of N. This happens to be correct when reclaiming from
two block groups, but undercounts the clusters from three block groups
onwards. The incorrect cache value is also used immediately to update
i_blocks.
Assign the updated on-disk count to the cache, matching the allocation and
inode refresh paths.
In a QEMU test using a clean 256 MiB OCFS2 image and a 10,000-file
create/delete workload, the first buggy reclaim left the on-disk
(fe->i_clusters) and cached (ip_clusters) counts at 2048 and 512 clusters
respectively; later reclaims underflowed the cache. With this change, the
cache matched the on-disk count across all four reclaims: 2048, 1536,
1024, and 512 clusters.
Link: https://lore.kernel.org/20260805113920.385959-1-matthias.goergens@gmail.com
Fixes: 4a54331616 ("ocfs2: give ocfs2 the ability to reclaim suballocator free bg")
Signed-off-by: Matthias Goergens <matthias.goergens@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
A lockdep warning indicates a circular locking dependency between
`&oi->ip_xattr_sem` and `&journal->j_trans_barrier`:
WARNING: possible circular locking dependency detected
is trying to acquire lock:
(&oi->ip_xattr_sem){++++}-{4:4}, at: ocfs2_init_acl+0x2fd/0x7e0
fs/ocfs2/acl.c:367
but task is already holding lock:
(&journal->j_trans_barrier){.+.+}-{4:4}, at: ocfs2_start_trans+0x3ab/0x700
fs/ocfs2/journal.c:369
The deadlock involves two code paths: Path 1 (setxattr) where
`ocfs2_xattr_set()` acquires `ip_xattr_sem` (write) and then starts a
transaction, which acquires `j_trans_barrier` (read); and Path 2
(mkdir/mknod) where `ocfs2_mknod()` starts a transaction (`j_trans_barrier`
read) and then calls `ocfs2_init_acl()`, which attempts to acquire
`ip_xattr_sem` (read) on the parent directory to retrieve the default ACL.
Because rw_semaphores are subject to writer priority, a pending writer on
`j_trans_barrier` (e.g., the journal commit thread) can cause Path 1 to
block, while Path 2 is blocked waiting for Path 1 to release
`ip_xattr_sem`.
The patch fixes the lock ordering by precomputing the ACL state before
starting the OCFS2 transaction, while preserving POSIX ACL storage
semantics and the existing inode/security initialization order. By reading
the parent directory's default ACL and preparing the new inode's ACLs
outside the transaction, `ip_xattr_sem` is always acquired before
`j_trans_barrier`.
`struct ocfs2_acl_state` encapsulates the prepared ACL state, while
`ocfs2_acl_init_prepare()` and `ocfs2_acl_init_release()` avoid code
duplication between `ocfs2_mknod()` and `ocfs2_init_security_and_acl()`.
`ocfs2_calc_xattr_init()` and `ocfs2_init_acl()` use this precomputed
state, removing internal `ip_xattr_sem` acquisition and redundant disk
reads.
Additionally, remove the `ip_xattr_sem` acquisition from
`ocfs2_xattr_set_handle()`. This function is only used while initializing a
new inode that has not yet been inserted into the inode hash or attached to
a dentry, meaning there is no risk of concurrent access and the lock is
unnecessary.
Link: https://lore.kernel.org/4094de06-9b69-4174-b2ee-08126dffc693@mail.kernel.org
Fixes: 16c8d569f5 ("ocfs2/acl: use 'ip_xattr_sem' to protect getting extended attribute")
Signed-off-by: Krystian Kaniewski <krystianmkaniewski@gmail.com>
Assisted-by: Gemini:gemini-3.5-flash Gemini:gemini-3.1-pro-preview syzbot
Reported-by: syzbot+4007ab5229e732466d9f@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=4007ab5229e732466d9f
Link: https://syzkaller.appspot.com/ai_job?id=cc75363d-c672-499e-8fc5-44bcdc1cee39
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[BUG]
A corrupted append-DIO dinode (high byte at offset 0xa1
corrupted from 0 to 1) can carry an i_dio_orphaned_slot
outside the mounted filesystem slot range and trigger a
use-after-free error:
BUG: KASAN: slab-use-after-free in ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102
Read of size 8 at addr ffff88800b767c00 by task kworker/u8:3/85
Call Trace:
...
ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102
ocfs2_wipe_inode+0x292/0xf70 fs/ocfs2/inode.c:840
ocfs2_delete_inode fs/ocfs2/inode.c:1155 [inline]
ocfs2_evict_inode+0x6c9/0x1170 fs/ocfs2/inode.c:1295
evict+0x38e/0x8f0 fs/inode.c:810
iput_final fs/inode.c:1914 [inline]
iput fs/inode.c:1966 [inline]
iput+0x55b/0x8b0 fs/inode.c:1926
ocfs2_recover_orphans+0x610/0xe40 fs/ocfs2/journal.c:2374
ocfs2_complete_recovery+0x5af/0xd00 fs/ocfs2/journal.c:1373
...
[CAUSE]
ocfs2_del_inode_from_orphan() uses i_dio_orphaned_slot to index the
slot-local system inode cache. The dinode validator does not check
this active slot, so an out-of-range value produces an invalid cache
entry pointer that is dereferenced as an inode pointer.
[FIX]
Reject an active i_dio_orphaned_slot outside the slot range during
dinode validation, before DIO orphan recovery can consume it.
Link: https://lore.kernel.org/20260803030007.3993199-3-gality369@gmail.com
Fixes: 06ee5c75b5 ("ocfs2: add functions to add and remove inode in orphan dir")
Signed-off-by: ZhengYuan Huang <gality369@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "ocfs2: validate active orphan slots during inode read".
OCFS2 trusts active ordinary and append-DIO orphan slots read from dinodes.
A corrupted slot can therefore index osb_orphan_wipes or the slot-local
system-inode cache outside their allocations before the corruption is
reported.
Patch 1 validates the ordinary orphan slot used by inode wipe processing.
Patch 2 validates the append-DIO orphan slot used by DIO completion and
orphan recovery. Both checks reject corrupt metadata at the existing inode
validation boundary.
This patch (of 2):
[BUG]
A corrupted dinode with OCFS2_ORPHANED_FL can carry an
i_orphaned_slot outside the mounted filesystem slot range.
ocfs2_wipe_inode() uses it to index osb_orphan_wipes before looking
up the orphan directory, causing an out-of-bounds memory access.
BUG: KASAN: slab-use-after-free in ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102
Read of size 8 at addr ffff88800b767c00 by task kworker/u8:3/85
Call Trace:
...
ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102
ocfs2_wipe_inode+0x292/0xf70 fs/ocfs2/inode.c:840
ocfs2_delete_inode fs/ocfs2/inode.c:1155 [inline]
ocfs2_evict_inode+0x6c9/0x1170 fs/ocfs2/inode.c:1295
evict+0x38e/0x8f0 fs/inode.c:810
iput_final fs/inode.c:1914 [inline]
iput fs/inode.c:1966 [inline]
iput+0x55b/0x8b0 fs/inode.c:1926
ocfs2_recover_orphans+0x610/0xe40 fs/ocfs2/journal.c:2374
ocfs2_complete_recovery+0x5af/0xd00 fs/ocfs2/journal.c:1373
...
[CAUSE]
ocfs2_validate_inode_block() validates i_suballoc_slot but leaves
the active ordinary orphan slot unchecked. Downstream consumers
assume that the value is smaller than osb->max_slots.
[FIX]
Reject an active i_orphaned_slot outside the slot range during
dinode validation, before the inode reaches orphan wipe processing.
Link: https://lore.kernel.org/20260803030007.3993199-1-gality369@gmail.com
Link: https://lore.kernel.org/20260803030007.3993199-2-gality369@gmail.com
Fixes: b4df6ed8db ("[PATCH] ocfs2: fix orphan recovery deadlock")
Signed-off-by: ZhengYuan Huang <gality369@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The test creates a non-anonymous VMA (ptr_not_anon) via mmap() with
MAP_PRIVATE but without MAP_ANONYMOUS, using fd=0 (stdin) as the file
descriptor. This always fails because fd=0 is not a regular file, and the
failure was hidden because ASSERT_NE() incorrectly checked for NULL
instead of MAP_FAILED.
Fix by using mkstemp() + ftruncate() to create a real temporary file, then
mapping it with MAP_PRIVATE to obtain a genuine file-backed VMA. Also fix
the mmap() error checks to use MAP_FAILED instead of NULL, and pass fd=-1
for the anonymous mapping for clarity. The temp file is unlinked
immediately so it does not persist on disk.
Link: https://lore.kernel.org/20260803103046.14324-1-hongfu.li@linux.dev
Signed-off-by: Hongfu Li <lihongfu@kylinos.cn>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
LTP project recently switched to patchwork.kernel.org, document it. Add
also IRC channel.
Link: 3590f66120
Link: https://lore.kernel.org/ltp/20260731054548.133241-1-pvorel@suse.cz/
Link: https://lore.kernel.org/20260803115821.238704-1-pvorel@suse.cz
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Suggested-by: Cyril Hrubis <chrubis@suse.cz>
Reviewed-by: Cyril Hrubis <chrubis@suse.cz>
Reviewed-by: Li Wang <li.wang@linux.dev>
Reviewed-by: Andrea Cervesato <andrea.cervesato@suse.com>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Ben Copeland <ben.copeland@linaro.org>
Cc: Jan Stancek <jstancek@redhat.com>
Cc: Tim Bird <tim.bird@sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit resolves an issue where modpost section verification fails due
to section mismatches between list_add and its callers.
At present, list_add (and its internal __list_add) are called from both
.text and .init code sections. Since inlining can vary per call site,
list_add can be 4 different states:
list_add in text with arguments to non-.init.data values
list_add in init with arguments to static .init.data values
list_add in init with arguments to non-.init.data values
list_add in text with arguments to static .init.data values
It is last instance that ends up causing the section mismatch caused by
constant propagation of the address of static libs inside the `dir_add` as
seen below (with the dir_list being defined statically in initramfs.c,
resting in .init.data).
WARNING: modpost: vmlinux.o: section mismatch in reference: __list_add
(section: .text.unlikely.) -> dir_list (section: .init.data)
Because of these section matching requirements, semantically, __list_add
and list_add MUST be inlined. This will then ensure callers inside .init
will receive a list_add that exists and refers to only .init data, and
list_add code in .text sections will only refer to non-init data.
This issue manifests predominently in AutoFDO with clang, which is very
hesitant to inline cold functions such as list_add even when marked
`inline`. Marking them as `__always_inline` therefore matches the
existing semantic constraints imposed by modpost's section mismatch
checks.
Link: https://lore.kernel.org/20260731-always-inline-list-add-v1-1-d29f54ce5477@google.com
Link: https://lore.kernel.org/all/CANn89iJVQe=wedLheJmjZjOTJsWHijT0jZs=iRxKssJZbjAxHw@mail.gmail.com/
Signed-off-by: Jordan R Abrahams-Whitehead <ajordanr@google.com>
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Suggested-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reported-by: Giuliano Procida <gprocida@google.com>
Reported-by: Yabin Cui <yabinc@google.com>
Closes: https://github.com/ClangBuiltLinux/linux/issues/2173
Cc: Bill Wendling <morbo@google.com>
Cc: Justin Stitt <justinstitt@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
page_owner_sort opens the output file with "w" before reading the input.
If both paths refer to the same file, this truncates the input and the
tool silently processes zero records before returning success.
Delay opening the output file until all input records have been loaded
into memory. This allows the tool to sort a file in place without
truncating data before it has been consumed.
Link: https://lore.kernel.org/20260730015809.3819606-1-warren.xiong@ugreen.com
Signed-off-by: Warren Xiong <warren.xiong@ugreen.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vishal Moola <vishal.moola@gmail.com>
Cc: Ye Liu <ye.liu@linux.dev>
Cc: Zhen Ni <zhen.ni@easystack.cn>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The help text still says the feature only covers mutexes, but blocker
tracking has since been extended to semaphores and rwsems. Update the
description to match the supported lock types.
Link: https://lore.kernel.org/20260730061854.176547-1-wangxb12@chinatelecom.cn
Cc: Petr Mladek <pmladek@suse.com>
Signed-off-by: Xibo Wang <wangxb12@chinatelecom.cn>
Suggested-by: Lance Yang <lance.yang@linux.dev>
Reviewed-by: Lance Yang <lance.yang@linux.dev>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
cmd_attr_register_cpumask() and cmd_attr_deregister_cpumask() differed
only in which attribute they parsed and which action they passed on, so
take both as arguments. __free(free_cpumask_var) then removes the goto.
No functional change.
Link: https://lore.kernel.org/20260728202104.17839-3-include@grrlz.net
Signed-off-by: Bradley Morgan <include@grrlz.net>
Cc: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "taskstats: tidy up the cpumask command path".
Two small cleanups from reading kernel/taskstats.c. No functional change in
either one.
This patch (of 2):
taskstats_user_cmd() only calls the cpumask handlers after checking the
same info->attrs[] entry, so parse() never sees a NULL attribute. Drop
the check and its odd "return 1", which no caller tested for anyway.
No functional change.
Link: https://lore.kernel.org/20260728202104.17839-1-include@grrlz.net
Link: https://lore.kernel.org/20260728202104.17839-2-include@grrlz.net
Signed-off-by: Bradley Morgan <include@grrlz.net>
Cc: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reduce the number of uint32_t <-> size_t conversions a little.
Eliminating such conversions entirely would require changing almost all
uint32_t to size_t, which would look confusing and increase the sizes of
the structs even more. Going the other way, converting everything to
uint32_t, isn't possible because the input and output buffers use size_t
in struct xz_buf.
Now both arguments to min() have the same type. This is required to for
compatibility with PowerPC boot code[1] whose min() is strict like
include/linux/minmax.h was before the commit d03eba99f5 ("minmax: allow
min()/max()/clamp() if the arguments have the same signedness.").
Swap the order of the "state" and "len" in struct lzma_dec to avoid
padding in the middle of the struct when size_t is 64 bits. The
reordering doesn't change the size of the struct; the padding just appears
at the end instead.
dict_flush() used to truncate size_t to uint32_t when returning. This
wasn't a bug; the value is always small enough.
Link: https://lore.kernel.org/20260614160521.924710-1-lasse.collin@tukaani.org
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Reported-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://lore.kernel.org/lkml/20260610232323.GA1071374@ax162/ [1]
Reviewed-by: Thorsten Blum <thorsten.blum@linux.dev>
Cc: David Laight <david.laight.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
proc_ipc_dointvec_minmax_orphans() currently calls shm_destroy_orphaned()
whenever shm_rmid_forced is set, including on sysctl reads. Reading
/proc/sys/kernel/shm_rmid_forced should not take shm_ids rwsem for write
and walk all segments.
Only run the cleanup when the sysctl is written and the forced RMID policy
is enabled.
When shm_rmid_forced=1, monitoring tools that read
/proc/sys/kernel/shm_rmid_forced trigger the cleanup on every read.
Link: https://lore.kernel.org/all/?q=only+destroy+orphaned+shm+segments+on+sysctl+write
Link: https://lore.kernel.org/tencent_738A8BC6E9EA205F555E4B0DAA154D4F8E0A@qq.com
Signed-off-by: Jianlin Shi <shijianlin11@foxmail.com>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use the simpler min() macro since the values are unsigned and compatible.
Link: https://lore.kernel.org/20260609150030.634570-1-lasse.collin@tukaani.org
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Reviewed-by: Lasse Collin <lasse.collin@tukaani.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
map_dump() closes the map fd in its error path, and do_dump() then
closes the same fd again after a successful dump. Closing an already
closed fd leaves errno set to EBADF, which poisons later errno checks
such as the batch file read check in do_batch(). Let do_dump() own the
fd and remove the close from map_dump().
The same double-close pattern exists in do_show_subset(): both
show_map_close_json() and show_map_close_plain() already close the fd,
so drop the extra close() there as well.
Also propagate the error when bpf_map_get_info_by_fd() fails on a
subsequent map in do_dump(): set err = -1 before breaking out of the
loop, so a later failure is not silently hidden after an earlier
iteration succeeded.
Fixes: 99f9863a0c ("bpftool: Match maps by name")
Signed-off-by: Yuan Chen <chenyuan@kylinos.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260810142224.2907373-2-chenyuan_fl@163.com
The verifier keeps per-subprogram metadata in three parallel arrays:
subprog_info, func_info, and func_info_aux. Dead code elimination can
remove whole subprograms, and adjust_subprog_starts_after_remove()
shifts subprog_info and func_info to close the gap, but leaves
func_info_aux in place. From that point on, func_info_aux[i] no longer
describes subprogram i.
Shift func_info_aux together with func_info so the three arrays stay
aligned after subprogram removal.
Reported-by: Sashiko <sashiko-bot@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260808064523.DE3E71F000E9@smtp.kernel.org
Link: https://lore.kernel.org/bpf/20260812231506.3558128-1-memxor@gmail.com
The following sequence may leads race between event_define_fields()
and update_event_fields():
CPU0 (loads module A) CPU1 (loads module B)
=============================== ===============================
load_module(A) load_module(B)
notifier_call_chain notifier_call_chain
trace_module_notify trace_module_notify
mutex_lock(&event_mutex) trace_event_update_all()
trace_module_add_events(A) down_write(&trace_event_sem)
__register_event(call_A)
__add_event_to_tracers(call_A)
event_define_fields(call_A)
for each f: list_for_each_entry(field,
list_add(&f->link, &class->fields, link)
&class->fields) field = class->fields->next;
Where access to the class->fields is not protected by the event_mutex in
trace_event_update_all().
This produces the following panic:
Unable to handle kernel access ... at virtual address 0000000000000018
pc : update_event_fields+0xf8/0x368
Call trace:
update_event_fields+0xf8/0x368
trace_event_update_all+0x7c/0x2b4
trace_module_notify+0x4c/0x1dc
notifier_call_chain+0x84/0x168
blocking_notifier_call_chain_robust+0x64/0xd4
load_module+0x10c8/0x123c
__arm64_sys_finit_module+0x230/0x31c
Fix by taking event_mutex in trace_event_update_all() before
trace_event_sem.
Cc: stable@vger.kernel.org
Fixes: b3bc8547d3 ("tracing: Have TRACE_DEFINE_ENUM affect trace event types as well")
Link: https://patch.msgid.link/2e5730d2-c631-da41-3a3a-ae35bb4895f3@allwinnertech.com
Signed-off-by: Michael Wu <michael@allwinnertech.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
A module-only event filter such as ":mod:foo" is cached with a NULL
event_mod->match when foo has not been loaded. If a later write tries to
remove a specific match from the same module, remove_cache_mod() passes
the NULL cached match to strcmp(), causing a NULL pointer dereference.
The issue can be reproduced from userspace:
echo ':mod:trace_events_kunit_missing' > /sys/kernel/tracing/set_event
echo '!foo_bar:mod:trace_events_kunit_missing' >> /sys/kernel/tracing/set_event
The second write must be a concatenation (">>") to not include O_TRUNC as
that would cause ftrace_clear_events() to clear the cached modules lines.
The crash was reproduced on x86_64 QEMU while KUnit workers contended on
the event tracing path:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
RIP: 0010:strcmp+0x10/0x30
Call Trace:
__ftrace_set_clr_event_nolock+0x373/0x4a0
ftrace_set_clr_event+0xf0/0x180
ftrace_event_write+0xdf/0x110
vfs_write+0xf6/0x440
ksys_write+0x68/0xe0
do_syscall_64+0xf9/0x540
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Check event_mod->match before comparing it, consistent with the existing
NULL checks for the cached system and event fields. The mismatched removal
continues to return -EINVAL; a broad cached module filter is removed with
"!:mod:<module>".
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260811173902.1927376-2-sh_def@163.com
Fixes: b355247df1 ("tracing: Cache \":mod:\" events for modules not loaded yet")
Reported-by: syzbot+4d3143c8e28f6266c636@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/lkml/6a7a6b7f.9c11d2ce.289b96.00f8.GAE@google.com/
Signed-off-by: Hui Su <sh_def@163.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Move the tas2781-specific calibration start kcontrol initialization logic
out of tasdevice_create_cali_ctrls() into a new dedicated helper function
create_tas2781_cali_start_ktrl().
This change eliminates duplicate inline code in the main calibration
control registration routine, improves code readability, and makes further
extension for custom calibration parameters much easier. No functional
behavior changes.
Signed-off-by: Shenghao Ding <shenghao-ding@ti.com>
Link: https://patch.msgid.link/20260813080540.1030-1-shenghao-ding@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The error signaling is configured for the vast majority of devices and it's
extremely rare that it fires anyway. Removing the pcie check will allow
userspace to be notified on errors for legacy PCI devices. The Internal
Shared Memory (ISM) device on s390 is one such device. For PCI devices on
IBM s390 error recovery involves platform firmware and notification to
operating system is done by architecture specific way. So the ISM device
can still be recovered when notified of an error.
Reviewed-by: Julian Ruess <julianr@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Alex Williamson <alex@shazbot.org>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Link: https://lore.kernel.org/r/20260630165553.725-4-alifm@linux.ibm.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
For zPCI devices, we have platform specific error information. The platform
firmware provides this error information to the operating system in an
architecture specific mechanism. To enable recovery from userspace for
these devices, we want to expose this error information to userspace. Add a
new device feature to expose this information.
Userspace needs to be provide a buffer of fixed size. This size is provided
to userspace via the VFIO_DEVICE_INFO_CAP_ZPCI_BASE capability.
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Link: https://lore.kernel.org/r/20260630165553.725-3-alifm@linux.ibm.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
IOMMUFD selftest TRIGGER_IOPF borrows an attach handle from
group->pasid_array without synchronizing against PASID detach,
then a concurrent iommu_report_device_fault() can dereference
that borrowed handle's domain pointer after the detach erases
the handle and frees the backing struct iommufd_attach_handle.
TRIGGER_IOPF then dereferences the freed handle, causing a UAF.
Fix by adding a iopf_rwsem in mock_dev to follow the expected design
of a real driver. Hold its read side across the whole
iommu_report_device_fault() call, and its write side around every
path that attaches, detaches, or replaces a device domain.
This can block new reports and drains in-flight reports before an old
attach handle or the IOPF fault parameter can be removed.
Also take the write side while registering a mock device, since
it can invoke the mock driver's default-domain attach callback.
Closes: https://lore.kernel.org/all/D5E3AA41600B2056+f4e15662-bd2b-43ea-91cb-518de429e72c@smail.nju.edu.cn/
Fixes: ddee199710 ("iommufd/selftest: Add IOPF support for mock device")
Cc: stable@vger.kernel.org
Suggested-by: Jason Gunthorpe <jgg@ziepe.ca>
Assisted-by: Codex:gpt-5.6-terra
Signed-off-by: Peiyang He <peiyang_he@smail.nju.edu.cn>
Link: https://patch.msgid.link/38C8DF0A118B7176+20260811095551.2756745-1-peiyang_he@smail.nju.edu.cn
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Leon Hwang says:
====================
bpf: Introduce global percpu data
This patch set introduces global percpu data, similar to commit
6316f78306 ("Merge branch 'support-global-data'"), to reduce restrictions
in C for BPF programs.
With this enhancement, it becomes possible to define and use global percpu
variables, like the DEFINE_PER_CPU() macro in the kernel
include/linux/percpu-defs.h.
The section name for global peurcpu data is ".percpu". Even though, a one-byte
percpu variable (e.g., char run SEC(".percpu") = 0;) can trigger a crash
with Clang 17 [1], users are expected to use such small variables as global
percpu data with newer Clang versions, which don't have the issue.
The idea stems from the bpfsnoop [2], which itself was inspired by
retsnoop [3]. During testing of bpfsnoop on the v6.6 kernel, two LBR
(Last Branch Record) entries were observed related to the
bpf_get_smp_processor_id() helper.
Since commit 1ae6921009 ("bpf: inline bpf_get_smp_processor_id() helper"),
the bpf_get_smp_processor_id() helper has been inlined on x86_64, reducing
the overhead and consequently minimizing these two LBR records.
However, the introduction of global percpu data offers a more robust
solution. By leveraging the percpu_array map and percpu instruction,
global percpu data can be implemented intrinsically.
This feature also facilitates sharing percpu information between tail
callers and callees or between freplace callers and callees through a
shared global percpu variable. Previously, this was achieved using a
1-entry percpu_array map, which this patch set aims to improve upon.
Links:
[1] https://lore.kernel.org/bpf/fd1b3f58-c27f-403d-ad99-644b7d06ecb3@linux.dev/
[2] https://github.com/bpfsnoop/bpfsnoop
[3] https://github.com/anakryiko/retsnoop
Changes:
v11 -> v12:
* Improve feature check in bpf_object__create_maps() in libbpf.
* Add percpu_array map support in bpf_map__set_value_size() in libbpf.
* Exercise bpf_map__set_value_size() in selftest.
* Drop dead warning in bpf_object__populate_internal_map() in libbpf.
(Sashiko)
* v11: https://lore.kernel.org/bpf/20260806163125.11172-1-leon.hwang@linux.dev/
v10 -> v11:
* Drop env->prog->jit_requested check when inlining insns for global
percpu data.
* Do not autocreate percpu_array map when kernel does not have global
percpu data support in libbpf.
* Check map->btf_value_type_id in bpftool's is_skel_data().
* Exercise bpf_map__lookup_elem() in selftest.
* Collect Reviewed-by tags from Emil, thanks.
* Drop all duplicate blank lines in kernel/bpf/*.c. (Emil)
* Factor out check_map_mem_read() helper. (Emil)
* Check bpf_jit_supports_percpu_insn() first in
percpu_array_map_direct_value_addr/meta(). (Emil)
* Add comment for 'map->libbpf_type == LIBBPF_MAP_PERCPU' in libbpf's
map_is_mmapable(). (Emil)
* Init update_flags as a const var in libbpf's
bpf_object__populate_internal_map(). (Emil)
* Keep is_mmapable_map() beyond is_skel_data() in bpftool. (Emil)
* Add 'run' and 'cpu_id' in selftest. (Emil)
* Drop subskel test. Verify the generated subskel manually. (Emil)
* Add comment to the raw insns in selftest. (Emil)
* v10: https://lore.kernel.org/bpf/20260715153254.92010-1-leon.hwang@linux.dev/
v9 -> v10:
* Rebase latest bpf-next tree to resolve code conflict in verifier in
patch #1.
* v9: https://lore.kernel.org/bpf/20260713154024.30851-1-leon.hwang@linux.dev/
v8 -> v9:
* Use real name for percpu data maps in libbpf in patch #4.
* Add long map name test in patch #6.
* Move parse_cpu_mask_file() to test_percpu_data_on_cpus() in test in
patch #6.
* Validate map type in get_map_ident() for percpu data maps in patch #5.
* Update code comment in verifier in patch #2. (per Andrii)
* Pass 'type' to internal_map_name in libbpf in patch #4. (per Andrii)
* Factor out the helper is_skel_data() in bpftool in patch #5.
(per Quentin and Andrii)
* v8: https://lore.kernel.org/bpf/20260629152406.52582-1-leon.hwang@linux.dev/
v7 -> v8:
* Send patch #1 and #2 separately that fix interpreter fallback issues.
(Andrii)
* Use 'array->elem_size' to avoid 'range' local variable in
percpu_array_map_direct_value_meta(). (Andrii)
* Keep original map name for percpu data's map in libbpf. (Andrii)
* Factor out helper bpf_map_is_skel_data() in bpftool. (Andrii)
* Update commit message of direct access read-only percpu_array map.
(Andrii)
* Add test to verify that it is disallowed to directly write data of
read-only percpu_array map. (Andrii)
* Drop unused 'num_cpus' in test. (bot+bpf-ci)
* Factor out helper test_percpu_data_on_cpus() in test. (bot+bpf-ci)
* v7: https://lore.kernel.org/bpf/20260622143557.22955-1-leon.hwang@linux.dev/
v6 -> v7:
* Use tgt_endian() in bpf_gen__map_update_elem() in patch #6. (Sashiko)
* Use sizeof(args) in verifier_snprintf test in patch #10. (Sashiko)
* Drop xlated test of v6. (Alexei)
* v6: https://lore.kernel.org/bpf/20260615152646.27639-1-leon.hwang@linux.dev/
v5 -> v6:
* Prevent running user addr_space_cast and addr_percpu insns in
interpreter. (Sashiko)
* Cast __percpu pointer to u64 with (__force unsigned long). (lkp)
* Exclude BPF_MAP_TYPE_PERCPU_ARRAY in check_mem_access() before calling
bpf_map_direct_read(), and add a test to verify it.
(Sashiko, bot+bpf-ci)
* Skip percpu data variables for subskeleton in bpftool. (Sashiko)
* Protect skel->percpu using mprotect(..., PROT_READ) in light skeleton.
(Sashiko, bot+bpf-ci)
* Drop roundup() in tests. (Sashiko)
* Call test_global_percpu_data_verifier_log() without
test__start_subtest(). (Sashiko)
* Cast insn->imm to __u64 with (__u32) in xlated test. (Sashiko)
* Check cnt using the new idx in xlated test. (Sashiko)
* v5: https://lore.kernel.org/bpf/20260608145113.65857-1-leon.hwang@linux.dev/
v4 -> v5:
* Add prog->jit_requested check to prevent running percpu data in
interpreter in patch #1.
* Factor out verifier log tests using its own patch.
* Address comments from Alexei:
* Move map_type check from check_mem_access() to bpf_map_direct_read()
in patch #2.
* Move BPF_MAP_TYPE_INSN_ARRAY map_type check from const_reg_xfer() to
bpf_map_direct_read() in patch #2.
* Add a test to verify that the off of xlated ldimm64 insn matches the
off encoded in the ELF ldimm64 insn.
* Drop patch #5 of v4.
* Address reviews from Sashiko:
* Update commit message of patch #6 to indicate that maps.percpu->mmaped
has been marked as read-only in libbpf.
* Lookup elem on specified CPU using BPF_F_CPU in tests.
* Drop unnecessary err == -EOPNOTSUPP in test.
* Locate target field using its offset in the iter test.
* v4: https://lore.kernel.org/bpf/20260414132421.63409-1-leon.hwang@linux.dev/
v3 -> v4:
* Drop duplicate blank lines in verifier.
* Add percpu data feature probe in libbpf.
* Update percpu_array map using BPF_F_ALL_CPUS flag for lskel, if no cpu flag
is set.
* Add two tests to verify verifier log.
* Add a test to verify mov64_percpu_reg instruction.
* Add a test to verify bpf_iter for percpu data map.
* Update percpu_array map using BPF_F_ALL_CPUS flag in libbpf
(per Alexei and Andrii).
* Address comments from Andrii:
* Use .percpu as section identifier.
* Use bpf_jit_supports_percpu_insn() instead of CONFIG_SMP.
* Drop bpf_map__is_internal_percpu() API.
* Drop unnecessary __aligned(8) in libbpf, verified by selftest.
* Make mmap data read-only after loading prog.
v3: https://lore.kernel.org/bpf/20250526162146.24429-1-leon.hwang@linux.dev/
v2 -> v3:
* Use ".data..percpu" as PERCPU_DATA_SEC.
* Address comment from Alexei:
* Add u8, array of ints and struct { .. } vars to selftest.
v2: https://lore.kernel.org/bpf/20250213161931.46399-1-leon.hwang@linux.dev/
v1 -> v2:
* Address comments from Andrii:
* Use LIBBPF_MAP_PERCPU and SEC_PERCPU.
* Reuse mmaped of libbpf's struct bpf_map for .percpu map data.
* Set .percpu struct pointer to NULL after loading skeleton.
* Make sure value size of .percpu map is __aligned(8).
* Use raw_tp and opts.cpu to test global percpu variables on all CPUs.
* Address comments from Alexei:
* Test non-zero offset of global percpu variable.
* Test case about BPF_PSEUDO_MAP_IDX_VALUE.
v1: https://lore.kernel.org/bpf/20250127162158.84906-1-leon.hwang@linux.dev/
rfc -> v1:
* Address comments from Andrii:
* Keep one image of global percpu variable for all CPUs.
* Reject non-ARRAY map in bpf_map_direct_read(), check_reg_const_str(),
and check_bpf_snprintf_call() in verifier.
* Split out libbpf changes from kernel-side changes.
* Use ".percpu" as PERCPU_DATA_SEC.
* Use enum libbpf_map_type to distinguish BSS, DATA, RODATA and
PERCPU_DATA.
* Avoid using errno for checking err from libbpf_num_possible_cpus().
* Use "map '%s': " prefix for error message.
rfc: https://lore.kernel.org/bpf/20250113152437.67196-1-leon.hwang@linux.dev/
====================
Link: https://patch.msgid.link/20260813152324.97937-1-leon.hwang@linux.dev
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Add a test to verify that it is OK to iter the percpu_array map used for
global percpu data.
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/20260813152324.97937-11-leon.hwang@linux.dev
Add two tests to verify the verifier log
"R%d points to percpu_array map which cannot be used as const string\n".
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/20260813152324.97937-10-leon.hwang@linux.dev
Verify these two cases:
1. Direct reading the data of read-only percpu data's percpu_array map
is allowed.
2. Direct writing the data of read-only percpu data's percpu_array map
is disallowed.
Assisted-by: Codex:gpt-5.5-xhigh
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260813152324.97937-9-leon.hwang@linux.dev
If the arch, like s390x, does not support percpu insn, these cases won't
test global percpu data by checking FEAT_PERCPU_DATA support.
The following APIs have been tested for global percpu data:
1. bpf_map__set_initial_value()
2. bpf_map__initial_value()
3. bpf_map__set_value_size()
4. generated percpu struct pointer pointing to internal map's mmaped data
5. bpf_map__lookup_elem() for global percpu data map
6. bpf_map_lookup_elem_flags() for global percpu data map
At the same time, the case is also tested with 'bpftool gen skeleton -L'.
Assisted-by: Codex:gpt-5.5-xhigh
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260813152324.97937-8-leon.hwang@linux.dev
Enhance bpftool to generate skeletons that properly handle global percpu
variables. The generated skeleton now includes a dedicated structure for
percpu data, allowing users to initialize and access percpu variables more
efficiently.
For global percpu variables, the skeleton now includes a nested
structure, e.g.:
struct test_global_percpu_data {
struct bpf_object_skeleton *skeleton;
struct bpf_object *obj;
struct {
struct bpf_map *percpu;
} maps;
// ...
struct test_global_percpu_data__percpu {
int data;
char run;
struct {
char set;
int i;
int nums[7];
} struct_data;
int nums[7];
} *percpu;
// ...
};
* The "struct test_global_percpu_data__percpu *percpu" points to
initialized data, which is actually "maps.percpu->mmaped".
* Before loading the skeleton, updating the
"struct test_global_percpu_data__percpu *percpu" modifies the initial
value of the corresponding global percpu variables.
* After loading the skeleton, "maps.percpu->mmaped" has been marked as
read-only in libbpf. If users want to update the global percpu
variables, they have to update the "maps.percpu" map instead.
* For lightweight skeleton, "lskel->percpu" will be protected by
"mprotect(p, sz, PROT_READ)".
* For subskeleton, those variables of global percpu data will be
skipped.
Assisted-by: Codex:gpt-5.5-xhigh
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20260813152324.97937-7-leon.hwang@linux.dev
Add support for global percpu data in libbpf by adding a new ".percpu"
section, similar to ".data". It enables efficient handling of percpu
global variables in bpf programs.
When generating loader for lightweight skeleton, update the percpu_array
map used for global percpu data using BPF_F_ALL_CPUS, in order to update
values across all CPUs using one value slot.
Unlike global data, the mmaped data for global percpu data will be marked
as read-only after populating the percpu_array map. Thereafter, users can
read those initialized percpu data after loading prog. If they want to
update the percpu data after loading prog, they have to update the
percpu_array map using key=0 instead.
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260813152324.97937-6-leon.hwang@linux.dev
libbpf needs a reliable way to distinguish kernels that can support
global percpu data from those that cannot.
Add a dedicated feature probe, so libbpf can make capability decisions
early and fail predictably when global percpu data is unavailable.
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260813152324.97937-5-leon.hwang@linux.dev
Introduce global percpu data, inspired by the commit
6316f78306 ("Merge branch 'support-global-data'"). It enables the
definition of global percpu variables in BPF, similar to the
include/linux/percpu-defs.h::DEFINE_PER_CPU() macro.
For example, in BPF, it is able to define a global percpu variable like:
int data SEC(".percpu");
With this patch, tools like retsnoop [1] and bpfsnoop [2] can simplify
their BPF code for handling LBRs. The code can be updated from
static struct perf_branch_entry lbrs[1][MAX_LBR_ENTRIES] SEC(".data.lbrs");
to
static struct perf_branch_entry lbrs[MAX_LBR_ENTRIES] SEC(".percpu.lbrs");
This eliminates the need to retrieve the CPU ID using the
bpf_get_smp_processor_id() helper.
Additionally, by reusing global percpu data map, sharing information
between tail callers and callees or freplace callers and callees becomes
simpler compared to reusing percpu_array maps.
Links:
[1] https://github.com/anakryiko/retsnoop
[2] https://github.com/bpfsnoop/bpfsnoop
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260813152324.97937-4-leon.hwang@linux.dev
In the next commit, percpu_array map will add map_direct_value_addr
support.
IOW, it will add a map_type check in the iff condition of the
bpf_map_direct_read() code block, which will reduce the code block
readability.
Hence, factor out check_map_mem_read helper to improve the readability,
and the maintainability for the percpu_array map case.
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260813152324.97937-3-leon.hwang@linux.dev
There are many adjacent blank lines in kernel/bpf/ that have accumulated
over time.
Drop them for cleanup.
No functional changes intended.
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/20260813152324.97937-2-leon.hwang@linux.dev
The man page for pkey_alloc(2) specifies that it should return -1 with
the errno set to ENOSPC when pkeys are not supported [1]. However, on
x86 pkey_alloc() sets errno to EINVAL when called for the first time
on a CPU that does not support pkeys.
The root cause of this is the x86 implementation of mm_pkey_alloc() not
directly checking if pkeys are supported. It only checks if all the
pkeys have been allocated by comparing the allocation map against
all_pkeys_mask. When OSPKE is not enabled, init_new_context() skips the
initialization of the allocation map, leaving it as 0, while
all_pkeys_mask is 1. mm_pkey_alloc() interprets this as there being a
pkey available and it returns pkey 0. Then, pkey_alloc() fails with
-EINVAL from arch_set_user_pkey_access() instead of returning -ENOSPC.
Subsequent calls to pkey_alloc() do return -ENOSPC because pkey 0 is
left marked as allocated.
Change mm_pkey_alloc() to directly check if OSPKE is enabled, and
return -1 if it is not, which causes pkey_alloc() to return -ENOSPC. The
arm64 and powerpc implementations of mm_pkey_alloc() already do this
check.
[1] https://man7.org/linux/man-pages/man2/pkey_alloc.2.html
[ dhansen: use arch_pkeys_enabled() to follow arm ]
Fixes: e8c24d3a23 ("x86/pkeys: Allocation/free syscalls")
Signed-off-by: Bijan Tabatabai <btabatabai@wisc.edu>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://patch.msgid.link/20260716220604.26452-1-bijan311@gmail.com
The cpuset partition root state selftest checks several CPU hotplug
transitions. If writing to a CPU online file fails, the helper still
runs pause afterwards and returns the status of pause instead of the
failed write.
This hides the real hotplug failure and can make later checks run
against expectations for a transition that never happened. Move the
write before the bookkeeping and return when it fails, so callers can
observe the hotplug error and the test does not record a CPU as offline
unless the offline operation actually succeeded.
Also change the O* command handler in set_ctrl_state() to use
"eval $COMM $REDIRECT" like all other handlers. The previous version
set COMM but still called write_cpu_online directly, bypassing the
redirect that captures stderr for error reporting.
Changes since v1:
- Use eval $COMM $REDIRECT in the O* handler instead of calling
write_cpu_online directly (Waiman Long)
Fixes: a8c52eba88 ("kselftest/cgroup: Add cpuset v2 partition root state test")
Signed-off-by: Rui Qi <qirui.001@bytedance.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
