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1,429,402 commits

Author SHA1 Message Date
Emil Tantilov
e111cbc4ad idpf: fix memory leak in idpf_vc_core_deinit()
Make sure to free hw->lan_regs. Reported by kmemleak during reset:

unreferenced object 0xff1b913d02a936c0 (size 96):
  comm "kworker/u258:14", pid 2174, jiffies 4294958305
  hex dump (first 32 bytes):
    00 00 00 c0 a8 ba 2d ff 00 00 00 00 00 00 00 00  ......-.........
    00 00 40 08 00 00 00 00 00 00 25 b3 a8 ba 2d ff  ..@.......%...-.
  backtrace (crc 36063c4f):
    __kmalloc_noprof+0x48f/0x890
    idpf_vc_core_init+0x6ce/0x9b0 [idpf]
    idpf_vc_event_task+0x1fb/0x350 [idpf]
    process_one_work+0x226/0x6d0
    worker_thread+0x19e/0x340
    kthread+0x10f/0x250
    ret_from_fork+0x251/0x2b0
    ret_from_fork_asm+0x1a/0x30

Fixes: 6aa53e861c ("idpf: implement get LAN MMIO memory regions")
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Reviewed-by: Joshua Hay <joshua.a.hay@intel.com>
Tested-by: Samuel Salin <Samuel.salin@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-01-06 15:42:10 -08:00
Emil Tantilov
f6242b3546 idpf: fix memory leak in idpf_vport_rel()
Free vport->rx_ptype_lkup in idpf_vport_rel() to avoid leaking memory
during a reset. Reported by kmemleak:

unreferenced object 0xff450acac838a000 (size 4096):
  comm "kworker/u258:5", pid 7732, jiffies 4296830044
  hex dump (first 32 bytes):
    00 00 00 00 00 10 00 00 00 10 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 10 00 00 00 00 00 00  ................
  backtrace (crc 3da81902):
    __kmalloc_cache_noprof+0x469/0x7a0
    idpf_send_get_rx_ptype_msg+0x90/0x570 [idpf]
    idpf_init_task+0x1ec/0x8d0 [idpf]
    process_one_work+0x226/0x6d0
    worker_thread+0x19e/0x340
    kthread+0x10f/0x250
    ret_from_fork+0x251/0x2b0
    ret_from_fork_asm+0x1a/0x30

Fixes: 0fe45467a1 ("idpf: add create vport and netdev configuration")
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
Tested-by: Samuel Salin <Samuel.salin@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-01-06 15:42:10 -08:00
Emil Tantilov
2e281e1155 idpf: detach and close netdevs while handling a reset
Protect the reset path from callbacks by setting the netdevs to detached
state and close any netdevs in UP state until the reset handling has
completed. During a reset, the driver will de-allocate resources for the
vport, and there is no guarantee that those will recover, which is why the
existing vport_ctrl_lock does not provide sufficient protection.

idpf_detach_and_close() is called right before reset handling. If the
reset handling succeeds, the netdevs state is recovered via call to
idpf_attach_and_open(). If the reset handling fails the netdevs remain
down. The detach/down calls are protected with RTNL lock to avoid racing
with callbacks. On the recovery side the attach can be done without
holding the RTNL lock as there are no callbacks expected at that point,
due to detach/close always being done first in that flow.

The previous logic restoring the netdevs state based on the
IDPF_VPORT_UP_REQUESTED flag in the init task is not needed anymore, hence
the removal of idpf_set_vport_state(). The IDPF_VPORT_UP_REQUESTED is
still being used to restore the state of the netdevs following the reset,
but has no use outside of the reset handling flow.

idpf_init_hard_reset() is converted to void, since it was used as such and
there is no error handling being done based on its return value.

Before this change, invoking hard and soft resets simultaneously will
cause the driver to lose the vport state:
ip -br a
<inf>	UP
echo 1 > /sys/class/net/ens801f0/device/reset& \
ethtool -L ens801f0 combined 8
ip -br a
<inf>	DOWN
ip link set <inf> up
ip -br a
<inf>	DOWN

Also in case of a failure in the reset path, the netdev is left
exposed to external callbacks, while vport resources are not
initialized, leading to a crash on subsequent ifup/down:
[408471.398966] idpf 0000:83:00.0: HW reset detected
[408471.411744] idpf 0000:83:00.0: Device HW Reset initiated
[408472.277901] idpf 0000:83:00.0: The driver was unable to contact the device's firmware. Check that the FW is running. Driver state= 0x2
[408508.125551] BUG: kernel NULL pointer dereference, address: 0000000000000078
[408508.126112] #PF: supervisor read access in kernel mode
[408508.126687] #PF: error_code(0x0000) - not-present page
[408508.127256] PGD 2aae2f067 P4D 0
[408508.127824] Oops: Oops: 0000 [#1] SMP NOPTI
...
[408508.130871] RIP: 0010:idpf_stop+0x39/0x70 [idpf]
...
[408508.139193] Call Trace:
[408508.139637]  <TASK>
[408508.140077]  __dev_close_many+0xbb/0x260
[408508.140533]  __dev_change_flags+0x1cf/0x280
[408508.140987]  netif_change_flags+0x26/0x70
[408508.141434]  dev_change_flags+0x3d/0xb0
[408508.141878]  devinet_ioctl+0x460/0x890
[408508.142321]  inet_ioctl+0x18e/0x1d0
[408508.142762]  ? _copy_to_user+0x22/0x70
[408508.143207]  sock_do_ioctl+0x3d/0xe0
[408508.143652]  sock_ioctl+0x10e/0x330
[408508.144091]  ? find_held_lock+0x2b/0x80
[408508.144537]  __x64_sys_ioctl+0x96/0xe0
[408508.144979]  do_syscall_64+0x79/0x3d0
[408508.145415]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[408508.145860] RIP: 0033:0x7f3e0bb4caff

Fixes: 0fe45467a1 ("idpf: add create vport and netdev configuration")
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
Tested-by: Samuel Salin <Samuel.salin@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-01-06 15:42:10 -08:00
Faisal Bukhari
1eb217ab2e perf parse-events: Fix evsel allocation failure
If evsel__new_idx() returns NULL, the function currently jumps to label
'out_err'.  Here, references to `cpus` and `pmu_cpus` are dropped.
Also, resources held by evsel->name and evsel->metric_id are freed.

But if evsel__new_idx() returns NULL, it can lead to NULL pointer
dereference.

Fixes: cd63c22168 ("perf parse-events: Minor __add_event refactoring")
Signed-off-by: Faisal Bukhari <faisalbukhari523@gmail.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2026-01-06 14:54:24 -08:00
Derek Foreman
75326c67aa perf data: Fix coding style
Adjust some oddly indented fprintf() calls.

Signed-off-by: Derek Foreman <derek.foreman@collabora.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06 19:34:07 -03:00
Ewan Chorynski
4348796233 rust: drm: Improve safety comment when using Pin::into_inner_unchecked
The safety requirements for `Pin::into_inner_unchecked` state that the
returned pointer must be treated as pinned until it is dropped. Such a
guarantee is provided by the `ARef` type. This patch improves the safety
comment to better reflect this.

Signed-off-by: Ewan Chorynski <ewan.chorynski@ik.me>
Link: https://patch.msgid.link/20251228-drm-gem-safety-comment-v2-1-99bb861c3371@ik.me
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-01-06 23:30:28 +01:00
Yu Liao
be5c6ec660 Documentation/kernel-parameters: Add tsa under mitigations=off
On X86 AMD systems, mitigations=off also disables the Transient
Scheduler Attacks (TSA) mitigation. Add it to the list.

Signed-off-by: Yu Liao <liaoyu.ly@bytedance.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251225121438.38427-1-liaoyu.ly@bytedance.com>
2026-01-06 15:23:27 -07:00
Akiyoshi Kurita
46b4bb702e docs: spufs: fix ppc64 architecture line break
Fix a broken line break in the word "architecture" in the spufs
documentation.

Signed-off-by: Akiyoshi Kurita <weibu@redadmin.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251225161615.3107808-1-weibu@redadmin.org>
2026-01-06 15:21:26 -07:00
Derek Foreman
8e746e95c3 perf data: Allow filtering conversion by time range
This adds a feature to allow restricting the range of converted samples
with a range string like perf-script and perf-report --time.

Committer testing:

Put a probe on the ICMP receive path handling broadcast packets:

  # perf probe icmp_rcv:64
  Added new event:
    probe:icmp_rcv_L64   (on icmp_rcv:64)

  You can now use it in all perf tools, such as:

  	perf record -e probe:icmp_rcv_L64 -aR sleep 1

  # perf record -e probe:icmp_rcv_L64 ping -c 10 -b 127.255.255.255
  WARNING: pinging broadcast address
  PING 127.255.255.255 (127.255.255.255) 56(84) bytes of data.
  ^C
  --- 127.255.255.255 ping statistics ---
  10 packets transmitted, 0 received, 100% packet loss, time 9217ms

  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.034 MB perf.data (10 samples) ]

  # perf script
              ping   52785 [009]  5847.300394: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5848.325018: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5849.349007: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5850.372979: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5851.396988: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5852.420954: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5853.444934: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5854.468926: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5855.492914: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5856.516883: probe:icmp_rcv_L64: (ffffffffaadb337e)
  #

Now get some slices using perf script:

  # perf script --time 40%
            ping   52785 [009]  5847.300394: probe:icmp_rcv_L64: (ffffffffaadb337e)
            ping   52785 [009]  5848.325018: probe:icmp_rcv_L64: (ffffffffaadb337e)
            ping   52785 [009]  5849.349007: probe:icmp_rcv_L64: (ffffffffaadb337e)
            ping   52785 [009]  5850.372979: probe:icmp_rcv_L64: (ffffffffaadb337e)
  # perf script --time 40%-60%
            ping   52785 [009]  5851.396988: probe:icmp_rcv_L64: (ffffffffaadb337e)
            ping   52785 [009]  5852.420954: probe:icmp_rcv_L64: (ffffffffaadb337e)
  #

And finally use this new feature:

  # perf data convert --to-json out.json --time 0%-10%
  [ perf data convert: Converted 'perf.data' into JSON data 'out.json' ]
  [ perf data convert: Converted and wrote 0.001 MB (1 samples) ]
  [ perf data convert: Skipped 9 samples ]
  # cat out.json
  {
  	"linux-perf-json-version": 1,
  	"headers": {
  		"header-version": 1,
  		"captured-on": "2026-01-06T22:26:40Z",
  		"data-offset": 520,
  		"data-size": 34648,
  		"feat-offset": 35168,
  		"hostname": "number",
  		"os-release": "6.17.12-300.fc43.x86_64",
  		"arch": "x86_64",
  		"cpu-desc": "AMD Ryzen 9 9950X3D 16-Core Processor",
  		"cpuid": "AuthenticAMD,26,68,0",
  		"nrcpus-online": 32,
  		"nrcpus-avail": 32,
  		"perf-version": "6.19.rc4.gf4c270685d3d",
  		"cmdline": [
  			"/home/acme/bin/perf"
  		]
  	},
  	"samples": [
  		{
  			"timestamp": 5847300394661,
  			"pid": 52785,
  			"tid": 52785,
  			"cpu": 9,
  			"comm": "ping",
  			"callchain": [
  				{
  					"ip": "0xffffffffaadb337f",
  					"symbol": "icmp_rcv",
  					"dso": "[kernel.kallsyms]"
  				}
  			],
  			"__probe_ip": "ffffffffaadb337e"
  		}
  	]
  }
  #

Signed-off-by: Derek Foreman <derek.foreman@collabora.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06 19:20:02 -03:00
Wu Canhong
ae350d7181 doc: input: fix typos in input.rst
'even codes' should be 'event codes' at the end of input.rst

Signed-off-by: Wu Canhong <canhong12@163.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251226160219.64818-1-canhong12@163.com>
2026-01-06 15:19:54 -07:00
Leon Romanovsky
80d9411c00 PCI/P2PDMA: Add missing struct p2pdma_provider documentation
Two fields in struct p2pdma_provider were not documented, which resulted
in the following kernel-doc warning:

  Warning: include/linux/pci-p2pdma.h:26 struct member 'owner' not described in 'p2pdma_provider'
  Warning: include/linux/pci-p2pdma.h:26 struct member 'bus_offset' not described in 'p2pdma_provider'

Repro:

  $ scripts/kernel-doc -none include/linux/pci-p2pdma.h

Fixes: f58ef9d1d1 ("PCI/P2PDMA: Separate the mmap() support from the core logic")
Reported-by: Bjorn Helgaas <helgaas@kernel.org>
Closes: https://lore.kernel.org/all/20260102234033.GA246107@bhelgaas
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Link: https://patch.msgid.link/20260104-fix-p2p-kdoc-v1-1-6d181233f8bc@nvidia.com
2026-01-06 16:18:02 -06:00
Christian Brauner
edecd1ae59
Merge patch series "vfs kernel-doc fixes for 6.19"
Bagas Sanjaya <bagasdotme@gmail.com> says:

Here are kernel-doc fixes for vfs subsystem targetting 6.19. This small
series is split from much larger kernel-doc fixes series I posted a while
ago [1].

* patches from https://patch.msgid.link/20251219024620.22880-1-bagasdotme@gmail.com:
  VFS: fix __start_dirop() kernel-doc warnings
  fs: Describe @isnew parameter in ilookup5_nowait()

Link: https://patch.msgid.link/20251219024620.22880-1-bagasdotme@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-06 23:17:57 +01:00
Bagas Sanjaya
ba4c74f80e
VFS: fix __start_dirop() kernel-doc warnings
Sphinx report kernel-doc warnings:

WARNING: ./fs/namei.c:2853 function parameter 'state' not described in '__start_dirop'
WARNING: ./fs/namei.c:2853 expecting prototype for start_dirop(). Prototype was for __start_dirop() instead

Fix them up.

Fixes: ff7c4ea11a ("VFS: add start_creating_killable() and start_removing_killable()")
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://patch.msgid.link/20251219024620.22880-3-bagasdotme@gmail.com
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-06 23:17:52 +01:00
Bagas Sanjaya
b0f5804b41
fs: Describe @isnew parameter in ilookup5_nowait()
Sphinx reports kernel-doc warning:

WARNING: ./fs/inode.c:1607 function parameter 'isnew' not described in 'ilookup5_nowait'

Describe the parameter.

Fixes: a27628f436 ("fs: rework I_NEW handling to operate without fences")
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://patch.msgid.link/20251219024620.22880-2-bagasdotme@gmail.com
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-06 23:17:52 +01:00
James Clark
523471c516 perf build: Skip nondistro build test if libbfd is old
Non distro builds now require a new version of libbfd, so skip the test
if the library is too old.

The grep test isn't a strong as the feature test in
test-libbfd-threadsafe.c, but there seems to be precedent for feature
testing this way here and it's good enough for the build-test rule. If
the function exists but returns an error it will be picked up by the
feature test when attempting the build.

Signed-off-by: James Clark <james.clark@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Bill Wendling <morbo@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06 19:15:49 -03:00
Thorsten Blum
736ea81026 Documentation: kernel-hacking: Remove :c:func: annotations
Remove the useless :c:func: annotations.

Suggested-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251222232506.2615-2-thorsten.blum@linux.dev>
2026-01-06 15:15:15 -07:00
James Clark
cff602f659 perf build: Feature test for libbfd thread safety API
The non-distro build requires libbfd 2.42 since commit b72b8132d8
("perf libbfd: Ensure libbfd is initialized prior to use"). Add a
feature test so that it's obvious why the build fails if this criteria
isn't met.

Signed-off-by: James Clark <james.clark@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Bill Wendling <morbo@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06 19:14:46 -03:00
James Clark
c0cb97a275 perf build: Remove unused libbfd-buildid feature test
HAVE_LIBBFD_BUILDID_SUPPORT isn't used in the codebase so remove the
feature test that sets it.

Signed-off-by: James Clark <james.clark@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Bill Wendling <morbo@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06 19:14:00 -03:00
Stephen Smalley
4f099d0940 nfs: unify security_inode_listsecurity() calls
commit 243fea1346 ("NFSv4.2: fix listxattr to return selinux
security label") introduced a direct call to
security_inode_listsecurity() in nfs4_listxattr(). However,
nfs4_listxattr() already indirectly called
security_inode_listsecurity() via nfs4_listxattr_nfs4_label() if
CONFIG_NFS_V4_SECURITY_LABEL is enabled and the server has the
NFS_CAP_SECURITY_LABEL capability enabled. This duplication was fixed
by commit 9acb237def ("NFSv4.2: another fix for listxattr") by
making the second call conditional on NFS_CAP_SECURITY_LABEL not being
set by the server. However, the combination of the two changes
effectively makes one call to security_inode_listsecurity() in every
case - which is the desired behavior since getxattr() always returns a
security xattr even if it has to synthesize one. Further, the two
different calls produce different xattr name ordering between
security.* and user.* xattr names. Unify the two separate calls into a
single call and get rid of nfs4_listxattr_nfs4_label() altogether.

Link: https://lore.kernel.org/selinux/CAEjxPJ6e8z__=MP5NfdUxkOMQ=EnUFSjWFofP4YPwHqK=Ki5nw@mail.gmail.com/
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2026-01-06 17:13:16 -05:00
James Clark
ae323bc241 perf build: Do all non-distro feature checks in one go
None of the if statements or variable assignments in the non-distro
block actually affect the feature checks. Just do them all in one place
so the flow isn't obscured.

Signed-off-by: James Clark <james.clark@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Bill Wendling <morbo@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06 19:11:13 -03:00
Bagas Sanjaya
bb51cf4f61 Documentation: kernel-hacking: Convert internal links
Convert internal cross-references in "Putting Your Stuff in the kernel"
section from inline code to internal links.

Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251223035254.22894-4-bagasdotme@gmail.com>
2026-01-06 15:08:43 -07:00
Bagas Sanjaya
2b79aafb17 Documentation: kernel-hacking: Do not italicize EXPORT_SYMBOL{,_GPL}() references
Do not italicize EXPORT_SYMBOL() and EXPORT_SYMBOL_GPL() references in
EXPORT_SYMBOL_NS() and EXPORT_SYMBOL_NS_GPL() subsections.

Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251223035254.22894-3-bagasdotme@gmail.com>
2026-01-06 15:08:43 -07:00
Bagas Sanjaya
b47e2b93aa Documentation: kernel-hacking: Remove current macro annotation
Remove unneeded :c:macro: annotation of current macro.

Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251223035254.22894-2-bagasdotme@gmail.com>
2026-01-06 15:08:43 -07:00
Christian Brauner
75ddaa4ddc
pidfs: protect PIDFD_GET_* ioctls() via ifdef
We originally protected PIDFD_GET_<ns-type>_NAMESPACE ioctls() through
ifdefs and recent rework made it possible to drop them. There was an
oversight though. When the relevant namespace is turned off ns->ops will
be NULL so even though opening a file descriptor is perfectly legitimate
it would fail during inode eviction when the file was closed.

The simple fix would be to check ns->ops for NULL and continue allow to
retrieve namespace fds from pidfds but we don't allow retrieving them
when the relevant namespace type is turned off. So keep the
simplification but add the ifdefs back in.

Link: https://lore.kernel.org/20251222214907.GA189632@quark
Link: https://patch.msgid.link/20251224-ununterbrochen-gagen-ea949b83f8f2@brauner
Fixes: a71e4f103a ("pidfs: simplify PIDFD_GET_<type>_NAMESPACE ioctls")
Tested-by: Brendan Jackman <jackmanb@kernel.org>
Tested-by: Eric Biggers <ebiggers@kernel.org>
Reported-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-06 23:08:12 +01:00
Roberto Sassu
7fc37b588a perf build: Remove FEATURE_CHECK_LDFLAGS-disassembler-{four-args,init-styled} setting
As the building mechanism is now able to retry detection with different
combinations of linking flags, setting FEATURE_CHECK_LDFLAGS-disassembler-four-args
and FEATURE_CHECK_LDFLAGS-disassembler-init-styled is not necessary anymore,
so remove it.

James Clark notes:

Use the same technique to find the set of bfd-related libraries to link as in:

  3308ffc5016e6136 ("tools, build: Retry detection of bfd-related features")

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andres Freund <andres@anarazel.de>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Bill Wendling <morbo@google.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Justin Stitt <justinstitt@google.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <qmo@kernel.org>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@google.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06 19:07:38 -03:00
Thomas Weißschuh
4ac85d9bc7
kbuild: uapi: split out command conditions into variables
The condition logic will become a bit more complicated.

Split them out into dedicated variables so they stay readable.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-4-d91545d794f7@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2026-01-06 15:07:32 -07:00
Thomas Weißschuh
e2772ba5f4
kbuild: uapi: don't compile test bpf_perf_event.h on xtensa
The xtensa UAPI headers do not provide 'struct pt_regs',
triggering an error:

usr/include/linux/bpf_perf_event.h:14:28: error: field 'regs' has incomplete type

Disable the header tests for this file on xtensa.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-3-d91545d794f7@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2026-01-06 15:07:32 -07:00
Thomas Weißschuh
cc45d2ea5c
hexagon: Drop invalid UAPI header asm/signal.h
This UAPI header contains declarations of internal kernel symbols.
Such declarations are invalid. Normally headers_check.pl would report
an error, but apparently its dependency on CC_CAN_LINK prevent its
execution on hexagon so far.

As the header does not expose any additional UAPI, just make it a
regular internal kernel header. asm-generic/signal.h will be used
for the UAPI automatically, the same as before.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-2-d91545d794f7@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2026-01-06 15:07:32 -07:00
Thomas Weißschuh
6059b880a9
kbuild: uapi: validate that headers do not use libc
The UAPI headers should be self-contained. That means they should not
use other headers from libc. Currently this is not enforced and various
dependencies have crept in.

Add a check to make sure no new ones are added.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-1-d91545d794f7@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2026-01-06 15:07:32 -07:00
Max Nikulin
3a8501b3a4 docs: admin: devices: remove /dev/cdwriter
Remove /dev/cdwriter from the local symlinks table and from the related
note.

Creation of the symlink was removed from udev in commit [1] that
became a part of release 115 in 2007 [2].

The altered text was added in 1995 [3].

[1] https://git.kernel.org/pub/scm/linux/hotplug/udev.git/commit/?id=b1a2b83f2d
    2007-08-11 14:06:03 +0200 Kay Sievers.
    rules: update Fedora rules

[2] https://git.kernel.org/pub/scm/linux/hotplug/udev.git/commit/?h=7e599863919
    2007-08-24 01:29:54 +0200 Kay Sievers.
    release 115

[3] https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/diff/Documentation/devices.txt?h=v2.5.45&id=6e995ea941a
    1995-11-21 Linus Torvalds.
    Import 1.3.43

Signed-off-by: Max Nikulin <manikulin@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <f5c3f6e9-cd92-47e3-89c3-06dbcfc98c17@gmail.com>
2026-01-06 15:06:30 -07:00
Ian Rogers
1ec205e366 perf test java symbol: Additional libperf-jvmti.so path check
If perf is built into an output directory then so is
libperf-jvmti.so.

If `perf test` is run from that directory then PWD needn't also be that
directory meaning libperf-jvmti.so won't be found and the test skipped.

Add an additional check for libperf-jvmti.so in the same directory as
the perf binary for this case, this avoids the test skipping.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06 19:06:00 -03:00
Akiyoshi Kurita
ae4f42ea4c docs: keystone: fix typo in knav-qmss documentation
Signed-off-by: Akiyoshi Kurita <weibu@redadmin.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251223112946.2580519-1-weibu@redadmin.org>
2026-01-06 15:03:19 -07:00
Nicolas Pitre
76df6815da
kconfig: Support conditional deps using "depends on X if Y"
Extend the "depends on" syntax to support conditional dependencies
using "depends on X if Y". While functionally equivalent to "depends
on X || (Y == n)", "depends on X if Y" is much more readable and
makes the kconfig language uniform in supporting the "if <expr>"
suffix.
This also improves readability for "optional" dependencies, which
are the subset of conditional dependencies where X is Y.
Previously such optional dependencies had to be expressed as
the counterintuitive "depends on X || !X", now this can be
represented as "depends on X if X".

The change is implemented by converting the "X if Y" syntax into the
"X || (Y == n)" syntax during "depends on" token processing.

Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
[Graham Roff: Rewrote commit message, updated patch, added tests]
Signed-off-by: Graham Roff <grahamr@qti.qualcomm.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://patch.msgid.link/20251215-kconfig_conditional_deps-v3-1-59519af0a5df@qti.qualcomm.com
[nathan: Minor adjustments to spacing]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2026-01-06 14:57:15 -07:00
Sasha Levin
78d979db6c docs: add AI Coding Assistants documentation
Add guidance for AI assistants and developers using AI tools for kernel
contributions, per the consensus reached at the 2025 Maintainers Summit.

Create Documentation/process/coding-assistants.rst with detailed guidance
on licensing, Signed-off-by requirements, and attribution format. The
README points AI tools to this documentation.

This will allow coding assistants to easily parse these instructions and
comply with guidelines set by the community.

Link: https://lwn.net/Articles/1049830/
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251223122110.2496946-1-sashal@kernel.org>
2026-01-06 14:55:06 -07:00
SeongJae Park
57a63f6549 Docs/translations/ko_KR: remove memory-barriers
The memory-barriers.txt Korean translation is quite outdated.  The last
update on the translation was made on 2022-10-10, by commit ee5a86f451
("docs/memory-barriers.txt/kokr: Fix confusing name of 'data dependency
barrier'").  After the date, the original memory-barriers.txt got seven
more changes so far.  The most recent one was made on 2025-11-05.  But
none of those are applied to the translation.

Maybe I can work again on keeping it updated.  But, given the
advancement of translation tools, I think it might not be worth keeping
it at all.  Remove the outdated translation.

If it turns out to be worthy to keep the translation and someone willing
to keep it updated steps up, this could be reverted.

This change was inspired from the last kernel summit discussion [1].

[1] https://lpc.events/event/19/contributions/2259/

Cc: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: SeongJae Park <sj@kernel.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251225014027.15948-1-sj@kernel.org>
2026-01-06 14:53:51 -07:00
SeongJae Park
8a12e3fbf2 docs: submitting-patches: suggest adding previous version links
For review of patches that revisioned multiple times, patch changelogs
are very useful.  Adding actual links to the previous versions can
further help the review.  Using such links, reviewers can double check
the changelog by themselves, and find previous discussions.  Nowadays
having such links (e.g., lore.kernel.org archive links) is easy and
reliable.  Suggest adding such links if available.

Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251225015447.16387-1-sj@kernel.org>
2026-01-06 14:52:48 -07:00
Breno Leitao
a6b9f5b2f0
fs/namei: Remove redundant DCACHE_MANAGED_DENTRY check in __follow_mount_rcu
The check for DCACHE_MANAGED_DENTRY at the start of __follow_mount_rcu()
is redundant because the only caller (handle_mounts) already verifies
d_managed(dentry) before calling this function, so, dentry in
__follow_mount_rcu() has always DCACHE_MANAGED_DENTRY set.

This early-out optimization never fires in practice - but it is marking
as likely().

This was detected with branch profiling, which shows 100% misprediction
in this likely.

Remove the whole if clause instead of removing the likely, given we
know for sure that dentry is not DCACHE_MANAGED_DENTRY.

Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260105-dcache-v1-1-f0d904b4a7c2@debian.org
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-06 22:48:15 +01:00
Mateusz Guzik
729d015ab2
fs: only assert on LOOKUP_RCU when built with CONFIG_DEBUG_VFS
Calls to the 2 modified routines are explicitly gated with checks for
the flag, so there is no use for this in production kernels.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://patch.msgid.link/20251229125751.826050-1-mjguzik@gmail.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-06 22:47:07 +01:00
Vincent Mailhol
90f1d896d5 doc-guide: kernel-doc: specify that W=n does not check header files
The documentation states that:

  make W=n

can be used to verify the documentation format. This is true for .c
files but not for headers [1].

Modify the documentation to specify that headers files are not covered
by make W=n and that these need to be checked separately with
scripts/kernel-doc.

[1] commit 3a025e1d1c ("Add optional check for bad kernel-doc comments")
Link: https://git.kernel.org/torvalds/c/3a025e1d1c2e

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251225-doc-format-check-v1-1-dff637a4d275@kernel.org>
2026-01-06 14:42:31 -07:00
Jeffrey Bencteux
bcb90a2834 audit: add missing syscalls to read class
The "at" variant of getxattr() and listxattr() are missing from the
audit read class. Calling getxattrat() or listxattrat() on a file to
read its extended attributes will bypass audit rules such as:

-w /tmp/test -p rwa -k test_rwa

The current patch adds missing syscalls to the audit read class.

Signed-off-by: Jeffrey Bencteux <jeff@bencteux.fr>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2026-01-06 16:42:29 -05:00
Thomas Richter
b04d2b9199 perf test: Fix test case perf evlist tests for s390x
Perf test case 78: perf evlist tests fails on s390.

The failure is causes by grouping events cycles and instructions because
sampling does only support event cycles.  Change the group to software
events to fix this.

Output before:
  # ./perf test 78
  78: perf evlist tests              : FAILED!
  #

Output after:
  # ./perf test 78
  78: perf evlist tests              : Ok
  #

Fixes: db452961de ("perf tests evlist: Add basic evlist test")
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Tested-by: Ian Rogers <irogers@google.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Jan Polensky <japo@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06 18:41:02 -03:00
Volodymyr Kot
5ce70894f6 Doc: correct spelling and wording mistakes
Fixed capitalization and punctuation in process documentation.

Signed-off-by: Volodymyr Kot <volodymyr.kot.ua@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251225133911.87512-1-volodymyr.kot.ua@gmail.com>
2026-01-06 14:39:58 -07:00
Vincent Mailhol
4971ca2007 docs: process: email-client: add Thunderbird "Toggle Line Wrap" extension
While reading the git-format-patch manpages [1], I discovered the existence
of the "Toggle Line Wrap" extension for Thunderbird which I found rather
convenient.

Looking at the history, the ancestor of this extension was added to the
documentation in commit e0e34e977a ("Documentation/email-clients.txt:
update Thunderbird docs with wordwrap plugin") but then removed in commit
f9a0974d3f ("Documentation: update thunderbird email client settings").

Extend the paragraph on Thunderbird's mailnews.wraplength register to
mention the existence of the "Toggle Line Wrap" extension. The goal is not
to create a war on what is the best option so make it clear that this is
just an alternative.

[1] man git-format-patch -- §Thunderbird
Link: https://git-scm.com/docs/git-format-patch#_thunderbird

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Acked-by: Sotir Danailov <sndanailov@gmail.com>  # As past commit author
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251226-docs_thunderbird-toggle-line-wrap-v2-1-aebb8c60025d@kernel.org>
2026-01-06 14:38:28 -07:00
Mustafa Elrasheid
8ee50b15d2 docs: Makefile: wrap SPHINXDIRS help text
When using `make help`, SPHINXDIR doesn't wrap around 80 characters,
causing text to overflow or wrap in incorrect ways,
which then makes the text difficult to read

Signed-off-by: Mustafa Elrasheid <mustafaelrasheid@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251227125244.6407-1-mustafaelrasheid@gmail.com>
2026-01-06 14:37:08 -07:00
Randy Dunlap
e970637707 docs: find-unused-docs.sh: fixup directory usage
The recent move of this script from scripts/ to tools/docs/
did not account for the 'cd' directory usage.
Update "cd .." to "cd ../.." to make the script self-correcting.

This also eliminates a shell warning:
./tools/docs/find-unused-docs.sh: line 33: cd: Documentation/: No such file or directory

Fixes: 184414c6a6 ("docs: move find-unused-docs.sh to tools/docs")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Fixes: 184414c6a6 (docs: move find-unused-docs.sh to tools/docs)
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260102200657.1040234-1-rdunlap@infradead.org>
2026-01-06 14:36:07 -07:00
Masaharu Noguchi
7f3f258daf docs/ja_JP: fix typos in submit-checklist.rst
Fix spelling errors in the Japanese translation:

- "Menu attibutes: default value" -> "Menu attributes: default value"
- "Documentaion/ABI/" -> "Documentation/ABI/"

No change in meaning intended.

Signed-off-by: Masaharu Noguchi <nogunix@gmail.com>
Acked-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260103-b4-practice-docs-typo-v1-1-d68ad6a22ab5@gmail.com>
2026-01-06 14:34:43 -07:00
Masaharu Noguchi
c7bba35efa docs/ja_JP: fix translation of freestanding C environment
The current Japanese translation incorrectly implies that the kernel is
independent of the C language.

Translate "freestanding C environment" accurately.

Signed-off-by: Masaharu Noguchi <nogunix@gmail.com>
Reviewed-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260104-ja-howto-v2-2-8cac525b3dfe@gmail.com>
2026-01-06 14:33:30 -07:00
Masaharu Noguchi
b09ee709a9 docs/ja_JP: fix typos and duplicated phrases in kernel development guide
Fix obvious typos and duplicated phrases in the Japanese translation.

No change in meaning intended.

Acked-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Masaharu Noguchi <nogunix@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260104-ja-howto-v2-1-8cac525b3dfe@gmail.com>
2026-01-06 14:33:30 -07:00
Robin Murphy
79448fa1f4 perf/arm_dsu: Allow standard cycles events
Since we do not use the divide-by-64 option, there should be no
significant difference between the dedicated cycle counter and the
standard cycles event. Since using the latter on DSU-120 now has
the side-effect of allowing multiple cycles events to be scheduled
simultaneously (beneficial for multiple cycle-based metrics), there
seems little reason not to allow the same on older DSUs as well.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2026-01-06 21:27:40 +00:00
Robin Murphy
85c0dbd8b6 perf/arm_dsu: Support DSU-120
DSU-120 has the same system register interface as previous DSUs, but
no longer offers a dedicated cycle counter. While this is not directly
discoverable via PMCR, the PMCCNTR register is still defined to exist
with RAZ/WI behaviour, allowing for a straightforward heuristic.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2026-01-06 21:27:40 +00:00