Main user visible change:
- User events can now have "multi formats"
The current user events have a single format. If another event is created
with a different format, it will fail to be created. That is, once an
event name is used, it cannot be used again with a different format. This
can cause issues if a library is using an event and updates its format.
An application using the older format will prevent an application using
the new library from registering its event.
A task could also DOS another application if it knows the event names, and
it creates events with different formats.
The multi-format event is in a different name space from the single
format. Both the event name and its format are the unique identifier.
This will allow two different applications to use the same user event name
but with different payloads.
- Added support to have ftrace_dump_on_oops dump out instances and
not just the main top level tracing buffer.
Other changes:
- Add eventfs_root_inode
Only the root inode has a dentry that is static (never goes away) and
stores it upon creation. There's no reason that the thousands of other
eventfs inodes should have a pointer that never gets set in its
descriptor. Create a eventfs_root_inode desciptor that has a eventfs_inode
descriptor and a dentry pointer, and only the root inode will use this.
- Added WARN_ON()s in eventfs
There's some conditionals remaining in eventfs that should never be hit,
but instead of removing them, add WARN_ON() around them to make sure that
they are never hit.
- Have saved_cmdlines allocation also include the map_cmdline_to_pid array
The saved_cmdlines structure allocates a large amount of data to hold its
mappings. Within it, it has three arrays. Two are already apart of it:
map_pid_to_cmdline[] and saved_cmdlines[]. More memory can be saved by
also including the map_cmdline_to_pid[] array as well.
- Restructure __string() and __assign_str() macros used in TRACE_EVENT().
Dynamic strings in TRACE_EVENT() are declared with:
__string(name, source)
And assigned with:
__assign_str(name, source)
In the tracepoint callback of the event, the __string() is used to get the
size needed to allocate on the ring buffer and __assign_str() is used to
copy the string into the ring buffer. There's a helper structure that is
created in the TRACE_EVENT() macro logic that will hold the string length
and its position in the ring buffer which is created by __string().
There are several trace events that have a function to create the string
to save. This function is executed twice. Once for __string() and again
for __assign_str(). There's no reason for this. The helper structure could
also save the string it used in __string() and simply copy that into
__assign_str() (it also already has its length).
By using the structure to store the source string for the assignment, it
means that the second argument to __assign_str() is no longer needed.
It will be removed in the next merge window, but for now add a warning if
the source string given to __string() is different than the source string
given to __assign_str(), as the source to __assign_str() isn't even used
and will be going away.
- Added checks to make sure that the source of __string() is also the
source of __assign_str() so that it can be safely removed in the next
merge window.
Included fixes that the above check found.
- Other minor clean ups and fixes
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Merge tag 'trace-v6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing updates from Steven Rostedt:
"Main user visible change:
- User events can now have "multi formats"
The current user events have a single format. If another event is
created with a different format, it will fail to be created. That
is, once an event name is used, it cannot be used again with a
different format. This can cause issues if a library is using an
event and updates its format. An application using the older format
will prevent an application using the new library from registering
its event.
A task could also DOS another application if it knows the event
names, and it creates events with different formats.
The multi-format event is in a different name space from the single
format. Both the event name and its format are the unique
identifier. This will allow two different applications to use the
same user event name but with different payloads.
- Added support to have ftrace_dump_on_oops dump out instances and
not just the main top level tracing buffer.
Other changes:
- Add eventfs_root_inode
Only the root inode has a dentry that is static (never goes away)
and stores it upon creation. There's no reason that the thousands
of other eventfs inodes should have a pointer that never gets set
in its descriptor. Create a eventfs_root_inode desciptor that has a
eventfs_inode descriptor and a dentry pointer, and only the root
inode will use this.
- Added WARN_ON()s in eventfs
There's some conditionals remaining in eventfs that should never be
hit, but instead of removing them, add WARN_ON() around them to
make sure that they are never hit.
- Have saved_cmdlines allocation also include the map_cmdline_to_pid
array
The saved_cmdlines structure allocates a large amount of data to
hold its mappings. Within it, it has three arrays. Two are already
apart of it: map_pid_to_cmdline[] and saved_cmdlines[]. More memory
can be saved by also including the map_cmdline_to_pid[] array as
well.
- Restructure __string() and __assign_str() macros used in
TRACE_EVENT()
Dynamic strings in TRACE_EVENT() are declared with:
__string(name, source)
And assigned with:
__assign_str(name, source)
In the tracepoint callback of the event, the __string() is used to
get the size needed to allocate on the ring buffer and
__assign_str() is used to copy the string into the ring buffer.
There's a helper structure that is created in the TRACE_EVENT()
macro logic that will hold the string length and its position in
the ring buffer which is created by __string().
There are several trace events that have a function to create the
string to save. This function is executed twice. Once for
__string() and again for __assign_str(). There's no reason for
this. The helper structure could also save the string it used in
__string() and simply copy that into __assign_str() (it also
already has its length).
By using the structure to store the source string for the
assignment, it means that the second argument to __assign_str() is
no longer needed.
It will be removed in the next merge window, but for now add a
warning if the source string given to __string() is different than
the source string given to __assign_str(), as the source to
__assign_str() isn't even used and will be going away.
- Added checks to make sure that the source of __string() is also the
source of __assign_str() so that it can be safely removed in the
next merge window.
Included fixes that the above check found.
- Other minor clean ups and fixes"
* tag 'trace-v6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (34 commits)
tracing: Add __string_src() helper to help compilers not to get confused
tracing: Use strcmp() in __assign_str() WARN_ON() check
tracepoints: Use WARN() and not WARN_ON() for warnings
tracing: Use div64_u64() instead of do_div()
tracing: Support to dump instance traces by ftrace_dump_on_oops
tracing: Remove second parameter to __assign_rel_str()
tracing: Add warning if string in __assign_str() does not match __string()
tracing: Add __string_len() example
tracing: Remove __assign_str_len()
ftrace: Fix most kernel-doc warnings
tracing: Decrement the snapshot if the snapshot trigger fails to register
tracing: Fix snapshot counter going between two tracers that use it
tracing: Use EVENT_NULL_STR macro instead of open coding "(null)"
tracing: Use ? : shortcut in trace macros
tracing: Do not calculate strlen() twice for __string() fields
tracing: Rework __assign_str() and __string() to not duplicate getting the string
cxl/trace: Properly initialize cxl_poison region name
net: hns3: tracing: fix hclgevf trace event strings
drm/i915: Add missing ; to __assign_str() macros in tracepoint code
NFSD: Fix nfsd_clid_class use of __string_len() macro
...
I'm sending you the sysctl pull request after following Luis' suggestion to
become a maintainer. If you see that something is missing, get back to me with
how to improve and I'll include your feedback in the following PRs.
Here is a summary of the changes included in this PR:
* New shared repo for sysctl maintenance
* check-sysctl-docs adjustment for API changes by Thomas Weißschuh
This is a non-functional PR. Additional testing is required for the rest of the
pending changes. Future kernel pull requests will include the removal of the
empty elements (sentinels) from sysctl arrays in the kernel/, net/, mm/ and
security/ dirs. After that, the superfluous check for procname == NULL will be
removed. And the push to avoid bloating the kernel as these arrays move out of
kernel/sysctl.c will be completed.
Even though Thomas' changes went into sysctl-next after v6.8-rc5 (3 weeks in
linux-next), I include them as they contained no functional changes and
therefore have little chance of resulting in an error/regression. Finally the
new shared repo is now picked up by linux-next and is the source for upcoming
sysctl changes.
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Merge tag 'sysctl-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl
Pull sysctl updates from Joel Granados:
"No functional changes - additional testing is required for the rest of
the pending changes.
- New shared repo for sysctl maintenance
- check-sysctl-docs adjustment for API changes by Thomas Weißschuh"
* tag 'sysctl-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl:
scripts: check-sysctl-docs: handle per-namespace sysctls
ipc: remove linebreaks from arguments of __register_sysctl_table
scripts: check-sysctl-docs: adapt to new API
MAINTAINERS: Update sysctl tree location
Fix:
Julia Lawall pointed out a null pointer dereference.
Cleanup:
Vlastimil Babka sent me a patch to remove some SLAB related code.
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Merge tag 'for-linus-6.9-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux
Pull orangefs updates from Mike Marshall:
"One fix, one cleanup...
Fix: Julia Lawall pointed out a null pointer dereference.
Cleanup: Vlastimil Babka sent me a patch to remove some SLAB related
code"
* tag 'for-linus-6.9-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
Julia Lawall reported this null pointer dereference, this should fix it.
fs/orangefs: remove ORANGEFS_CACHE_CREATE_FLAGS
In this round, there are a number of updates on mainly two areas: Zoned block
device support and Per-file compression. For example, we've found several issues
to support Zoned block device especially having large sections regarding to GC
and file pinning used for Android devices. In compression side, we've fixed many
corner race conditions that had broken the design assumption.
Enhancement:
- Support file pinning for Zoned block device having large section
- Enhance the data recovery after sudden power cut on Zoned block device
- Add more error injection cases to easily detect the kernel panics
- add a proc entry show the entire disk layout
- Improve various error paths paniced by BUG_ON in block allocation and GC
- support SEEK_DATA and SEEK_HOLE for compression files
Bug fix:
- fix to avoid use-after-free issue in f2fs_filemap_fault
- fix some race conditions to break the atomic write design assumption
- fix to truncate meta inode pages forcely
- resolve various per-file compression issues wrt the space management and
compression policies
- fix some swap-related bugs
In addition, we removed deprecated codes such as io_bits and heap_allocation,
and also fixed minor error handling routines with neat debugging messages.
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Merge tag 'f2fs-for-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs update from Jaegeuk Kim:
"In this round, there are a number of updates on mainly two areas:
Zoned block device support and Per-file compression. For example,
we've found several issues to support Zoned block device especially
having large sections regarding to GC and file pinning used for
Android devices. In compression side, we've fixed many corner race
conditions that had broken the design assumption.
Enhancements:
- Support file pinning for Zoned block device having large section
- Enhance the data recovery after sudden power cut on Zoned block
device
- Add more error injection cases to easily detect the kernel panics
- add a proc entry show the entire disk layout
- Improve various error paths paniced by BUG_ON in block allocation
and GC
- support SEEK_DATA and SEEK_HOLE for compression files
Bug fixes:
- avoid use-after-free issue in f2fs_filemap_fault
- fix some race conditions to break the atomic write design
assumption
- fix to truncate meta inode pages forcely
- resolve various per-file compression issues wrt the space
management and compression policies
- fix some swap-related bugs
In addition, we removed deprecated codes such as io_bits and
heap_allocation, and also fixed minor error handling routines with
neat debugging messages"
* tag 'f2fs-for-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (60 commits)
f2fs: fix to avoid use-after-free issue in f2fs_filemap_fault
f2fs: truncate page cache before clearing flags when aborting atomic write
f2fs: mark inode dirty for FI_ATOMIC_COMMITTED flag
f2fs: prevent atomic write on pinned file
f2fs: fix to handle error paths of {new,change}_curseg()
f2fs: unify the error handling of f2fs_is_valid_blkaddr
f2fs: zone: fix to remove pow2 check condition for zoned block device
f2fs: fix to truncate meta inode pages forcely
f2fs: compress: fix reserve_cblocks counting error when out of space
f2fs: compress: relocate some judgments in f2fs_reserve_compress_blocks
f2fs: add a proc entry show disk layout
f2fs: introduce SEGS_TO_BLKS/BLKS_TO_SEGS for cleanup
f2fs: fix to check return value of f2fs_gc_range
f2fs: fix to check return value __allocate_new_segment
f2fs: fix to do sanity check in update_sit_entry
f2fs: fix to reset fields for unloaded curseg
f2fs: clean up new_curseg()
f2fs: relocate f2fs_precache_extents() in f2fs_swap_activate()
f2fs: fix blkofs_end correctly in f2fs_migrate_blocks()
f2fs: ro: don't start discard thread for readonly image
...
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Merge tag 'vfs-6.9-rc1.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:
"This contains a few small fixes for this merge window:
- Undo the hiding of silly-rename files in afs. If they're hidden
they can't be deleted by rm manually anymore causing regressions
- Avoid caching the preferred address for an afs server to avoid
accidently overriding an explicitly specified preferred server
address
- Fix bad stat() and rmdir() interaction in afs
- Take a passive reference on the superblock when opening a block
device so the holder is available to concurrent callers from the
block layer
- Clear private data pointer in fscache_begin_operation() to avoid it
being falsely treated as valid"
* tag 'vfs-6.9-rc1.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
fscache: Fix error handling in fscache_begin_operation()
fs,block: get holder during claim
afs: Fix occasional rmdir-then-VNOVNODE with generic/011
afs: Don't cache preferred address
afs: Revert "afs: Hide silly-rename files from userspace"
Two regression fixes that had been introduced in the previous PR,
additional HD-audio quirks, and a further enhancement for the new
kunit.
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Merge tag 'sound-fix-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"Two regression fixes that had been introduced in this merge window,
additional HD-audio quirks, and a further enhancement for the new
kunit"
* tag 'sound-fix-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: core: add kunitconfig
ALSA: hda/realtek: add in quirk for Acer Swift Go 16 - SFG16-71
Revert "ALSA: usb-audio: Name feature ctl using output if input is PCM"
ALSA: timer: Fix missing irq-disable at closing
ALSA: hda/realtek: Add quirk for Lenovo Yoga 9 14IMH9
The __string() helper macro of the TRACE_EVENT() macro is used to
determine how much of the ring buffer needs to be allocated to fit the
given source string. Some trace events have a string that is dependent on
another variable that could be NULL, and in those cases the string is
passed in to be NULL.
The __string() macro can handle being passed in a NULL pointer for which
it will turn it into "(null)". It does that with:
strlen((src) ? (const char *)(src) : "(null)") + 1
But if src itself has the same conditional type it can confuse the
compiler. That is:
__string(r ? dev(r)->name : NULL)
Would turn into:
strlen((r ? dev(r)->name : NULL) ? (r ? dev(r)->name : NULL) : "(null)" + 1
For which the compiler thinks that NULL is being passed to strlen() and
gives this kind of warning:
./include/trace/stages/stage5_get_offsets.h:50:21: warning: argument 1 null where non-null expected [-Wnonnull]
50 | strlen((src) ? (const char *)(src) : "(null)") + 1)
Instead, create a static inline function that takes the src string and
will return the string if it is not NULL and will return "(null)" if it
is. This will then make the strlen() line:
strlen(__string_src(src)) + 1
Where the compiler can see that strlen() will not end up with NULL and
does not warn about it.
Note that this depends on commit 51270d573a ("tracing/net_sched: Fix
tracepoints that save qdisc_dev() as a string") being applied, as passing
the qdisc_dev() into __string_src() will give an error.
Link: https://lore.kernel.org/all/ZfNmfCmgCs4Nc+EH@aschofie-mobl2/
Link: https://lore.kernel.org/linux-trace-kernel/20240314232754.345cea82@rorschach.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reported-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The WARN_ON() check in __assign_str() to catch where the source variable
to the macro doesn't match the source variable to __string() gives an
error in clang:
>> include/trace/events/sunrpc.h:703:4: warning: result of comparison against a string literal is unspecified (use an explicit string comparison function instead) [-Wstring-compare]
670 | __assign_str(progname, "unknown");
That's because the __assign_str() macro has:
WARN_ON_ONCE((src) != __data_offsets.dst##_ptr_);
Where "src" is a string literal. Clang warns when comparing a string
literal directly as it is undefined to what the value of the literal is.
Since this is still to make sure the same string that goes to __string()
is the same as __assign_str(), for string literals do a test for that and
then use strcmp() in those cases
Note that this depends on commit 51270d573a ("tracing/net_sched: Fix
tracepoints that save qdisc_dev() as a string") being applied, as this was
what found that bug.
Link: https://lore.kernel.org/linux-trace-kernel/20240312113002.00031668@gandalf.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202402292111.KIdExylU-lkp@intel.com/
Fixes: 433e1d88a3be ("tracing: Add warning if string in __assign_str() does not match __string()")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There are two WARN_ON*() warnings in tracepoint.h that deal with RCU
usage. But when they trigger, especially from using a TRACE_EVENT()
macro, the information is not very helpful and is confusing:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at include/trace/events/lock.h:24 lock_acquire+0x2b2/0x2d0
Where the above warning takes you to:
TRACE_EVENT(lock_acquire, <<<--- line 24 in lock.h
TP_PROTO(struct lockdep_map *lock, unsigned int subclass,
int trylock, int read, int check,
struct lockdep_map *next_lock, unsigned long ip),
[..]
Change the WARN_ON_ONCE() to WARN_ONCE() and add a string that allows
someone to search for exactly where the bug happened.
Link: https://lore.kernel.org/linux-trace-kernel/20240228133112.0d64fb1b@gandalf.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Borislav Petkov <bp@alien8.de>
Tested-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Fixes Coccinelle/coccicheck warnings reported by do_div.cocci.
Compared to do_div(), div64_u64() does not implicitly cast the divisor and
does not unnecessarily calculate the remainder.
Link: https://lore.kernel.org/linux-trace-kernel/20240225164507.232942-2-thorsten.blum@toblux.com
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Currently ftrace only dumps the global trace buffer on an OOPs. For
debugging a production usecase, instance trace will be helpful to
check specific problems since global trace buffer may be used for
other purposes.
This patch extend the ftrace_dump_on_oops parameter to dump a specific
or multiple trace instances:
- ftrace_dump_on_oops=0: as before -- don't dump
- ftrace_dump_on_oops[=1]: as before -- dump the global trace buffer
on all CPUs
- ftrace_dump_on_oops=2 or =orig_cpu: as before -- dump the global
trace buffer on CPU that triggered the oops
- ftrace_dump_on_oops=<instance_name>: new behavior -- dump the
tracing instance matching <instance_name>
- ftrace_dump_on_oops[=2/orig_cpu],<instance1_name>[=2/orig_cpu],
<instrance2_name>[=2/orig_cpu]: new behavior -- dump the global trace
buffer and multiple instance buffer on all CPUs, or only dump on CPU
that triggered the oops if =2 or =orig_cpu is given
Also, the sysctl node can handle the input accordingly.
Link: https://lore.kernel.org/linux-trace-kernel/20240223083126.1817731-1-quic_hyiwei@quicinc.com
Cc: Ross Zwisler <zwisler@google.com>
Cc: <mhiramat@kernel.org>
Cc: <mark.rutland@arm.com>
Cc: <mcgrof@kernel.org>
Cc: <keescook@chromium.org>
Cc: <j.granados@samsung.com>
Cc: <mathieu.desnoyers@efficios.com>
Cc: <corbet@lwn.net>
Signed-off-by: Huang Yiwei <quic_hyiwei@quicinc.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The second parameter of __assign_rel_str() is no longer used. It can be removed.
Note, the only real users of rel_string is user events. This code is just
in the sample code for testing purposes.
This makes __assign_rel_str() different than __assign_str() but that's
fine. __assign_str() is used over 700 places and has a larger impact. That
change will come later.
Link: https://lore.kernel.org/linux-trace-kernel/20240223162519.2beb8112@gandalf.local.home
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In preparation to remove the second parameter of __assign_str(), make sure
it is really a duplicate of __string() by adding a WARN_ON_ONCE().
Link: https://lore.kernel.org/linux-trace-kernel/20240223161356.63b72403@gandalf.local.home
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There's no example code that uses __string_len(), and since the sample
code is used for testing the event logic, add a use case.
Link: https://lore.kernel.org/linux-trace-kernel/20240223152827.5f9f78e2@gandalf.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Now that __assign_str() gets the length from the __string() (and
__string_len()) macros, there's no reason to have a separate
__assign_str_len() macro as __assign_str() can get the length of the
string needed.
Also remove __assign_rel_str() although it had no users anyway.
Link: https://lore.kernel.org/linux-trace-kernel/20240223152206.0b650659@gandalf.local.home
Cc: Jeff Layton <jlayton@kernel.org>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reduce the number of kernel-doc warnings from 52 down to 10, i.e.,
fix 42 kernel-doc warnings by (a) using the Returns: format for
function return values or (b) using "@var:" instead of "@var -"
for function parameter descriptions.
Fix one return values list so that it is formatted correctly when
rendered for output.
Spell "non-zero" with a hyphen in several places.
Link: https://lore.kernel.org/linux-trace-kernel/20240223054833.15471-1-rdunlap@infradead.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/oe-kbuild-all/202312180518.X6fRyDSN-lkp@intel.com/
Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Running the ftrace selftests caused the ring buffer mapping test to fail.
Investigating, I found that the snapshot counter would be incremented
every time a snapshot trigger was added, even if that snapshot trigger
failed.
# cd /sys/kernel/tracing
# echo "snapshot" > events/sched/sched_process_fork/trigger
# echo "snapshot" > events/sched/sched_process_fork/trigger
-bash: echo: write error: File exists
That second one that fails increments the snapshot counter but doesn't
decrement it. It needs to be decremented when the snapshot fails.
Link: https://lore.kernel.org/linux-trace-kernel/20240223013344.729055907@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Fixes: 16f7e48ffc53a ("tracing: Add snapshot refcount")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Running the ftrace selftests caused the ring buffer mapping test to fail.
Investigating, I found that the snapshot counter would be incremented
every time a tracer that uses the snapshot is enabled even if the snapshot
was used by the previous tracer.
That is:
# cd /sys/kernel/tracing
# echo wakeup_rt > current_tracer
# echo wakeup_dl > current_tracer
# echo nop > current_tracer
would leave the snapshot counter at 1 and not zero. That's because the
enabling of wakeup_dl would increment the counter again but the setting
the tracer to nop would only decrement it once.
Do not arm the snapshot for a tracer if the previous tracer already had it
armed.
Link: https://lore.kernel.org/linux-trace-kernel/20240223013344.570525723@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Fixes: 16f7e48ffc53a ("tracing: Add snapshot refcount")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The TRACE_EVENT macros has some dependency if a __string() field is NULL,
where it will save "(null)" as the string. This string is also used by
__assign_str(). It's better to create a single macro instead of having
something that will not be caught by the compiler if there is an
unfortunate typo.
Link: https://lore.kernel.org/linux-trace-kernel/20240222211443.106216915@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The TRACE_EVENT() macro handles dynamic strings by having:
TP_PROTO(struct some_struct *s),
TP_ARGS(s),
TP_STRUCT__entry(
__string(my_string, s->string)
),
TP_fast_assign(
__assign_str(my_string, s->string);
)
TP_printk("%s", __get_str(my_string))
There's even some code that may call a function helper to find the
s->string value. The problem with the above is that the work to get the
s->string is done twice. Once at the __string() and again in the
__assign_str().
The length of the string is calculated via a strlen(), not once, but
twice. Once during the __string() macro and again in __assign_str(). But
the length is actually already recorded in the data location and here's no
reason to call strlen() again.
Just use the saved length that was saved in the __string() code for the
__assign_str() code.
Link: https://lore.kernel.org/linux-trace-kernel/20240222211442.793074999@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The TRACE_EVENT() macro handles dynamic strings by having:
TP_PROTO(struct some_struct *s),
TP_ARGS(s),
TP_STRUCT__entry(
__string(my_string, s->string)
),
TP_fast_assign(
__assign_str(my_string, s->string);
)
TP_printk("%s", __get_str(my_string))
There's even some code that may call a function helper to find the
s->string value. The problem with the above is that the work to get the
s->string is done twice. Once at the __string() and again in the
__assign_str().
But the __string() uses dynamic_array() which has a helper structure that
is created holding the offsets and length of the string fields. Instead of
finding the string twice, just save it off in another field from that
helper structure, and have __assign_str() use that instead.
Note, this also means that the second parameter of __assign_str() isn't
even used anymore, and may be removed in the future.
Link: https://lore.kernel.org/linux-trace-kernel/20240222211442.634192653@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The TP_STRUCT__entry that gets assigned the region name, or an
empty string if no region is present, is erroneously initialized
to the cxl_region pointer. It needs to be properly initialized
otherwise it's length is wrong and garbage chars can appear in
the kernel trace output: /sys/kernel/tracing/trace
The bad initialization was due in part to a naming conflict with
the parameter: struct cxl_region *region. The field 'region' is
already exposed externally as the region name, so changing that
to something logical, like 'region_name' is not an option. Instead
rename the internal only struct cxl_region to the commonly used
'cxlr'.
Impact is that tooling depending on that trace data can miss
picking up a valid event when searching by region name. The
TP_printk() output, if enabled, does emit the correct region
names in the dmesg log.
This was found during testing of the cxl-list option to report
media-errors for a region.
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: stable@vger.kernel.org
Fixes: ddf49d57b8 ("cxl/trace: Add TRACE support for CXL media-error records")
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The __string() and __assign_str() helper macros of the TRACE_EVENT() macro
are going through some optimizations where only the source string of
__string() will be used and the __assign_str() source will be ignored and
later removed.
To make sure that there's no issues, a new check is added between the
__string() src argument and the __assign_str() src argument that does a
strcmp() to make sure they are the same string.
The hclgevf trace events have:
__assign_str(devname, &hdev->nic.kinfo.netdev->name);
Which triggers the warning:
hclgevf_trace.h:34:39: error: passing argument 1 of ‘strcmp’ from incompatible pointer type [-Werror=incompatible-pointer-types]
34 | __assign_str(devname, &hdev->nic.kinfo.netdev->name);
[..]
arch/x86/include/asm/string_64.h:75:24: note: expected ‘const char *’ but argument is of type ‘char (*)[16]’
75 | int strcmp(const char *cs, const char *ct);
| ~~~~~~~~~~~~^~
Because __assign_str() now has:
WARN_ON_ONCE(__builtin_constant_p(src) ? \
strcmp((src), __data_offsets.dst##_ptr_) : \
(src) != __data_offsets.dst##_ptr_); \
The problem is the '&' on hdev->nic.kinfo.netdev->name. That's because
that name is:
char name[IFNAMSIZ]
Where passing an address '&' of a char array is not compatible with strcmp().
The '&' is not necessary, remove it.
Link: https://lore.kernel.org/linux-trace-kernel/20240313093454.3909afe7@gandalf.local.home
Cc: netdev <netdev@vger.kernel.org>
Cc: Yisen Zhuang <yisen.zhuang@huawei.com>
Cc: Salil Mehta <salil.mehta@huawei.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Yufeng Mo <moyufeng@huawei.com>
Cc: Huazhong Tan <tanhuazhong@huawei.com>
Cc: stable@vger.kernel.org
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Jijie Shao <shaojijie@huawei.com>
Fixes: d8355240cf ("net: hns3: add trace event support for PF/VF mailbox")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
I'm working on improving the __assign_str() and __string() macros to be
more efficient, and removed some unneeded semicolons. This triggered a bug
in the build as some of the __assign_str() macros in intel_display_trace
was missing a terminating semicolon.
Link: https://lore.kernel.org/linux-trace-kernel/20240222133057.2af72a19@gandalf.local.home
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@gmail.com>
Cc: stable@vger.kernel.org
Fixes: 2ceea5d880 ("drm/i915: Print plane name in fbc tracepoints")
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
I'm working on restructuring the __string* macros so that it doesn't need
to recalculate the string twice. That is, it will save it off when
processing __string() and the __assign_str() will not need to do the work
again as it currently does.
Currently __string_len(item, src, len) doesn't actually use "src", but my
changes will require src to be correct as that is where the __assign_str()
will get its value from.
The event class nfsd_clid_class has:
__string_len(name, name, clp->cl_name.len)
But the second "name" does not exist and causes my changes to fail to
build. That second parameter should be: clp->cl_name.data.
Link: https://lore.kernel.org/linux-trace-kernel/20240222122828.3d8d213c@gandalf.local.home
Cc: Neil Brown <neilb@suse.de>
Cc: Olga Kornievskaia <kolga@netapp.com>
Cc: Dai Ngo <Dai.Ngo@oracle.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: stable@vger.kernel.org
Fixes: d27b74a867 ("NFSD: Use new __string_len C macros for nfsd_clid_class")
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Instead of using UTS_RELEASE, use init_utsname()->release, which means that
we don't need to rebuild the code just for the git head commit changing.
Link: https://lore.kernel.org/linux-trace-kernel/20240222124639.65629-1-john.g.garry@oracle.com
Signed-off-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
User programs can now ask user_events to handle the synchronization of
multiple different formats for an event with the same name via the new
USER_EVENT_REG_MULTI_FORMAT flag.
Add a section for USER_EVENT_REG_MULTI_FORMAT that explains the intended
purpose and caveats of using it. Explain how deletion works in these
cases and how to use /sys/kernel/tracing/dynamic_events for per-version
deletion.
Link: https://lore.kernel.org/linux-trace-kernel/20240222001807.1463-5-beaub@linux.microsoft.com
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
User_events now has multi-format events which allow for the same
register name, but with different formats. When this occurs, different
tracepoints are created with unique names.
Add a new test that ensures the same name can be used for two different
formats. Ensure they are isolated from each other and that name and arg
matching still works if yet another register comes in with the same
format as one of the two.
Link: https://lore.kernel.org/linux-trace-kernel/20240222001807.1463-4-beaub@linux.microsoft.com
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Currently user_events supports 1 event with the same name and must have
the exact same format when referenced by multiple programs. This opens
an opportunity for malicious or poorly thought through programs to
create events that others use with different formats. Another scenario
is user programs wishing to use the same event name but add more fields
later when the software updates. Various versions of a program may be
running side-by-side, which is prevented by the current single format
requirement.
Add a new register flag (USER_EVENT_REG_MULTI_FORMAT) which indicates
the user program wishes to use the same user_event name, but may have
several different formats of the event. When this flag is used, create
the underlying tracepoint backing the user_event with a unique name
per-version of the format. It's important that existing ABI users do
not get this logic automatically, even if one of the multi format
events matches the format. This ensures existing programs that create
events and assume the tracepoint name will match exactly continue to
work as expected. Add logic to only check multi-format events with
other multi-format events and single-format events to only check
single-format events during find.
Change system name of the multi-format event tracepoint to ensure that
multi-format events are isolated completely from single-format events.
This prevents single-format names from conflicting with multi-format
events if they end with the same suffix as the multi-format events.
Add a register_name (reg_name) to the user_event struct which allows for
split naming of events. We now have the name that was used to register
within user_events as well as the unique name for the tracepoint. Upon
registering events ensure matches based on first the reg_name, followed
by the fields and format of the event. This allows for multiple events
with the same registered name to have different formats. The underlying
tracepoint will have a unique name in the format of {reg_name}.{unique_id}.
For example, if both "test u32 value" and "test u64 value" are used with
the USER_EVENT_REG_MULTI_FORMAT the system would have 2 unique
tracepoints. The dynamic_events file would then show the following:
u:test u64 count
u:test u32 count
The actual tracepoint names look like this:
test.0
test.1
Both would be under the new user_events_multi system name to prevent the
older ABI from being used to squat on multi-formatted events and block
their use.
Deleting events via "!u:test u64 count" would only delete the first
tracepoint that matched that format. When the delete ABI is used all
events with the same name will be attempted to be deleted. If
per-version deletion is required, user programs should either not use
persistent events or delete them via dynamic_events.
Link: https://lore.kernel.org/linux-trace-kernel/20240222001807.1463-3-beaub@linux.microsoft.com
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The current code for finding and deleting events assumes that there will
never be cases when user_events are registered with the same name, but
different formats. Scenarios exist where programs want to use the same
name but have different formats. An example is multiple versions of a
program running side-by-side using the same event name, but with updated
formats in each version.
This change does not yet allow for multi-format events. If user_events
are registered with the same name but different arguments the programs
see the same return values as before. This change simply makes it
possible to easily accommodate for this.
Update find_user_event() to take in argument parameters and register
flags to accommodate future multi-format event scenarios. Have find
validate argument matching and return error pointers to cover when
an existing event has the same name but different format. Update
callers to handle error pointer logic.
Move delete_user_event() to use hash walking directly now that
find_user_event() has changed. Delete all events found that match the
register name, stop if an error occurs and report back to the user.
Update user_fields_match() to cover list_empty() scenarios now that
find_user_event() uses it directly. This makes the logic consistent
across several callsites.
Link: https://lore.kernel.org/linux-trace-kernel/20240222001807.1463-2-beaub@linux.microsoft.com
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When a ring-buffer is memory mapped by user-space, no trace or
ring-buffer swap is possible. This means the snapshot feature is
mutually exclusive with the memory mapping. Having a refcount on
snapshot users will help to know if a mapping is possible or not.
Instead of relying on the global trace_types_lock, a new spinlock is
introduced to serialize accesses to trace_array->snapshot. This intends
to allow access to that variable in a context where the mmap lock is
already held.
Link: https://lore.kernel.org/linux-trace-kernel/20240220202310.2489614-4-vdonnefort@google.com
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The default behavior of ring_buffer_wait() when passed a NULL "cond"
parameter is to exit the function the first time it is woken up. The
current implementation uses a counter that starts at zero and when it is
greater than one it exits the wait_event_interruptible().
But this relies on the internal working of wait_event_interruptible() as
that code basically has:
if (cond)
return;
prepare_to_wait();
if (!cond)
schedule();
finish_wait();
That is, cond is called twice before it sleeps. The default cond of
ring_buffer_wait() needs to account for that and wait for its counter to
increment twice before exiting.
Instead, use the seq/atomic_inc logic that is used by the tracing code
that calls this function. Add an atomic_t seq to rb_irq_work and when cond
is NULL, have the default callback take a descriptor as its data that
holds the rbwork and the value of the seq when it started.
The wakeups will now increment the rbwork->seq and the cond callback will
simply check if that number is different, and no longer have to rely on
the implementation of wait_event_interruptible().
Link: https://lore.kernel.org/linux-trace-kernel/20240315063115.6cb5d205@gandalf.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 7af9ded0c2 ("ring-buffer: Use wait_event_interruptible() in ring_buffer_wait()")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Fix fscache_begin_operation() to clear cres->cache_priv on error, otherwise
fscache_resources_valid() will report it as being valid.
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/3933237.1710514106@warthog.procyon.org.uk
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reported-by: Marc Dionne <marc.dionne@auristor.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Now that we open block devices as files we need to deal with the
realities that closing is a deferred operation. An operation on the
block device such as e.g., freeze, thaw, or removal that runs
concurrently with umount, tries to acquire a stable reference on the
holder. The holder might already be gone though. Make that reliable by
grabbing a passive reference to the holder during bdev_open() and
releasing it during bdev_release().
Fixes: f3a608827d ("bdev: open block device as files") # mainline only
Reported-by: Christoph Hellwig <hch@infradead.org>
Link: https://lore.kernel.org/r/ZfEQQ9jZZVes0WCZ@infradead.org
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Reported-by: https://lore.kernel.org/r/CAHj4cs8tbDwKRwfS1=DmooP73ysM__xAb2PQc6XsAmWR+VuYmg@mail.gmail.com
Link: https://lore.kernel.org/r/20240315-freibad-annehmbar-ca68c375af91@brauner
Signed-off-by: Christian Brauner <brauner@kernel.org>
Core:
- i3c_bus_type is now const
Drivers:
- dw: disabling IBI is only allowed when hot join and SIR are disabled
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Merge tag 'i3c/for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux
Pull i3c updates from Alexandre Belloni:
"Not much this cycle with only three patches.
Core:
- i3c_bus_type is now const
Drivers:
- dw: disabling IBI is only allowed when hot join and SIR are disabled"
* tag 'i3c/for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux:
i3c: Make i3c_bus_type const
i3c: dw: Disable IBI IRQ depends on hot-join and SIR enabling
dt-bindings: i3c: drop "master" node name suffix
- Explicitly wipe BSS in the native EFI entrypoint, so that globals
shared with the legacy decompressor are zero-initialized correctly.
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Merge tag 'efi-fixes-for-v6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi
Pull EFI fix from Ard Biesheuvel:
"This fixes an oversight on my part in the recent EFI stub rework for
x86, which is needed to get Linux/x86 distro builds signed again for
secure boot by Microsoft. For this reason, most of this work is being
backported to v6.1, which is therefore also affected by this
regression.
- Explicitly wipe BSS in the native EFI entrypoint, so that globals
shared with the legacy decompressor are zero-initialized correctly"
* tag 'efi-fixes-for-v6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
x86/efistub: Clear decompressor BSS in native EFI entrypoint
delays and other oddities.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'timers-urgent-2024-03-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Ingo Molnar:
"Fix timer migration bug that can result in long bootup delays and
other oddities"
* tag 'timers-urgent-2024-03-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timer/migration: Remove buggy early return on deactivation
- Work around AMD erratum to filter out bogus LBR stack entries
- Fix incorrect PMU reset that can result in warnings (or worse)
during suspend/hibernation.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'perf-urgent-2024-03-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 perf event fixes from Ingo Molnar:
- Work around AMD erratum to filter out bogus LBR stack entries
- Fix incorrect PMU reset that can result in warnings (or worse)
during suspend/hibernation
* tag 'perf-urgent-2024-03-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/amd/core: Avoid register reset when CPU is dead
perf/x86/amd/lbr: Discard erroneous branch entries
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Merge tag 'linux-watchdog-6.9-rc1' of git://www.linux-watchdog.org/linux-watchdog
Pull watchdog updates from Wim Van Sebroeck:
- Remove usage of the deprecated ida_simple_xx() API
- Add kernel-doc for wdt_set_timeout()
- Add support for R-Car V4M, StarFive's JH8100 and sam9x7-wdt
- Fixes and small improvements
* tag 'linux-watchdog-6.9-rc1' of git://www.linux-watchdog.org/linux-watchdog:
watchdog: intel-mid_wdt: Get platform data via dev_get_platdata()
watchdog: intel-mid_wdt: Don't use "proxy" headers
watchdog: intel-mid_wdt: Remove unused intel-mid.h
dt-bindings: watchdog: sama5d4-wdt: add compatible for sam9x7-wdt
dt-bindings: watchdog: sprd,sp9860-wdt: convert to YAML
dt-bindings: watchdog: starfive,jh7100-wdt: Add compatible for JH8100
watchdog: stm32_iwdg: initialize default timeout
dt-bindings: watchdog: arm,sp805: document the reset signal
watchdog: sp805_wdt: deassert the reset if available
watchdog/hpwdt: Support Suspend and Resume
dt-bindings: watchdog: renesas-wdt: Add support for R-Car V4M
watchdog: starfive: check watchdog status before enabling in system resume
watchdog: starfive: Check pm_runtime_enabled() before decrementing usage counter
watchdog: qcom: fine tune the max timeout value calculation
watchdog: Add kernel-doc for wdt_set_timeout()
watchdog: core: Remove usage of the deprecated ida_simple_xx() API
Ricardo B. Marliere updated the PCMCIA intrastructure to make
use the driver core now allowing some structs to be const.
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Merge tag 'pcmcia-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux
Pull PCMCIA updates from Dominik Brodowski:
"Mark some structs 'const' now that the driver core supports it
(Ricardo B Marliere)"
* tag 'pcmcia-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux:
pcmcia: cs: make pcmcia_socket_class constant
pcmcia: ds: make pcmcia_bus_type const
- a new driver for Goodix Berlin I2C and SPI touch controllers
- support for IQS7222D v1.1 and v1.2 in iqs7222 driver
- support for IST3032C and IST3038B parts in Imagis touchscreen driver
- support for touch keys for Imagis touchscreen controllers
- support for Snakebyte GAMEPADs in xpad driver
- various cleanups and conversions to yaml for device tree bindings
- assorted fixes and cleanups
- old Synaptics navpoint driver has been removed since the only board
that used it (HP iPAQ hx4700) was removed a while ago.
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Merge tag 'input-for-v6.9-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input updates from Dmitry Torokhov:
- a new driver for Goodix Berlin I2C and SPI touch controllers
- support for IQS7222D v1.1 and v1.2 in iqs7222 driver
- support for IST3032C and IST3038B parts in Imagis touchscreen driver
- support for touch keys for Imagis touchscreen controllers
- support for Snakebyte GAMEPADs in xpad driver
- various cleanups and conversions to yaml for device tree bindings
- assorted fixes and cleanups
- old Synaptics navpoint driver has been removed since the only board
that used it (HP iPAQ hx4700) was removed a while ago.
* tag 'input-for-v6.9-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (37 commits)
Input: xpad - add support for Snakebyte GAMEPADs
dt-bindings: input: samsung,s3c6410-keypad: convert to DT Schema
Input: imagis - add touch key support
dt-bindings: input: imagis: Document touch keys
Input: imagis - use FIELD_GET where applicable
Input: make input_class constant
dt-bindings: input: atmel,captouch: convert bindings to YAML
Input: iqs7222 - add support for IQS7222D v1.1 and v1.2
dt-bindings: input: allwinner,sun4i-a10-lrad: drop redundant type from label
Input: serio - make serio_bus const
Input: synaptics-rmi4 - make rmi_bus_type const
Input: xilinx_ps2 - fix kernel-doc for xps2_of_probe function
input/touchscreen: imagis: add support for IST3032C
dt-bindings: input/touchscreen: imagis: add compatible for IST3032C
input/touchscreen: imagis: Add support for Imagis IST3038B
dt-bindings: input/touchscreen: Add compatible for IST3038B
input/touchscreen: imagis: Correct the maximum touch area value
Input: leds - change config symbol dependency for audio mute trigger
Input: ti_am335x_tsc - remove redundant assignment to variable config
Input: xpad - sort xpad_device by vendor and product ID
...
syzbot hit an assertion in copy up data loop which looks like it is
the result of a lower file whose size is being changed underneath
overlayfs.
This type of use case is documented to cause undefined behavior, so
returning EIO error for the copy up makes sense, but it should not be
causing a WARN_ON assertion.
Reported-and-tested-by: syzbot+3abd99031b42acf367ef@syzkaller.appspotmail.com
Fixes: ca7ab48240 ("ovl: add permission hooks outside of do_splice_direct()")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
In function ring_buffer_iter_empty(), cpu_buffer->commit_page is read
while other threads may change it. It may cause the time_stamp that read
in the next line come from a different page. Use READ_ONCE() to avoid
having to reason about compiler optimizations now and in future.
Link: https://lore.kernel.org/linux-trace-kernel/tencent_DFF7D3561A0686B5E8FC079150A02505180A@qq.com
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: linke li <lilinke99@qq.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In preparation for the ring-buffer memory mapping where each subbuf will
be accessible to user-space, zero all the page allocations.
Link: https://lore.kernel.org/linux-trace-kernel/20240220202310.2489614-2-vdonnefort@google.com
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The code that handles saved_cmdlines is split between the trace.c file and
the trace_sched_switch.c. There's some history to this. The
trace_sched_switch.c was originally created to handle the sched_switch
tracer that was deprecated due to sched_switch trace event making it
obsolete. But that file did not get deleted as it had some code to help
with saved_cmdlines. But trace.c has grown tremendously since then. Just
move all the saved_cmdlines code into trace_sched_switch.c as that's the
only reason that file still exists, and trace.c has gotten too big.
No functional changes.
Link: https://lore.kernel.org/linux-trace-kernel/20240220140703.497966629@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Mete Durlu <meted@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
In preparation of moving the saved_cmdlines logic out of trace.c and into
trace_sched_switch.c, replace the open coded manipulation of tgid_map in
set_tracer_flag() into a helper function trace_alloc_tgid_map() so that it
can be easily moved into trace_sched_switch.c without changing existing
functions in trace.c.
No functional changes.
Link: https://lore.kernel.org/linux-trace-kernel/20240220140703.338116216@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Mete Durlu <meted@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The saved_cmdlines have three arrays for mapping PIDs to COMMs:
- map_pid_to_cmdline[]
- map_cmdline_to_pid[]
- saved_cmdlines
The map_pid_to_cmdline[] is PID_MAX_DEFAULT in size and holds the index
into the other arrays. The map_cmdline_to_pid[] is a mapping back to the
full pid as it can be larger than PID_MAX_DEFAULT. And the
saved_cmdlines[] just holds the COMMs associated to the pids.
Currently the map_pid_to_cmdline[] and saved_cmdlines[] are allocated
together (in reality the saved_cmdlines is just in the memory of the
rounding of the allocation of the structure as it is always allocated in
powers of two). The map_cmdline_to_pid[] array is allocated separately.
Since the rounding to a power of two is rather large (it allows for 8000
elements in saved_cmdlines), also include the map_cmdline_to_pid[] array.
(This drops it to 6000 by default, which is still plenty for most use
cases). This saves even more memory as the map_cmdline_to_pid[] array
doesn't need to be allocated.
Link: https://lore.kernel.org/linux-trace-kernel/20240212174011.068211d9@gandalf.local.home/
Link: https://lore.kernel.org/linux-trace-kernel/20240220140703.182330529@goodmis.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Mete Durlu <meted@linux.ibm.com>
Fixes: 44dc5c41b5 ("tracing: Fix wasted memory in saved_cmdlines logic")
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
