When tracing is disabled, there's no reason that waiters should stay
waiting, wake them up, otherwise tasks get stuck when they should be
flushing the buffers.
Cc: stable@vger.kernel.org
Fixes: e30f53aad2 ("tracing: Do not busy wait in buffer splice")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The wake up waiters only checks the "wakeup_full" variable and not the
"full_waiters_pending". The full_waiters_pending is set when a waiter is
added to the wait queue. The wakeup_full is only set when an event is
triggered, and it clears the full_waiters_pending to avoid multiple calls
to irq_work_queue().
The irq_work callback really needs to check both wakeup_full as well as
full_waiters_pending such that this code can be used to wake up waiters
when a file is closed that represents the ring buffer and the waiters need
to be woken up.
Link: https://lkml.kernel.org/r/20220927231824.209460321@goodmis.org
Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 15693458c4 ("tracing/ring-buffer: Move poll wake ups into ring buffer code")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
If a page is partially read, and then the splice system call is run
against the ring buffer, it will always fail to read, no matter how much
is in the ring buffer. That's because the code path for a partial read of
the page does will fail if the "full" flag is set.
The splice system call wants full pages, so if the read of the ring buffer
is not yet full, it should return zero, and the splice will block. But if
a previous read was done, where the beginning has been consumed, it should
still be given to the splice caller if the rest of the page has been
written to.
This caused the splice command to never consume data in this scenario, and
let the ring buffer just fill up and lose events.
Link: https://lkml.kernel.org/r/20220927144317.46be6b80@gandalf.local.home
Cc: stable@vger.kernel.org
Fixes: 8789a9e7df ("ring-buffer: read page interface")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When executing following commands like what document said, but the log
"#### all functions enabled ####" was not shown as expect:
1. Set a 'mod' filter:
$ echo 'write*:mod:ext3' > /sys/kernel/tracing/set_ftrace_filter
2. Invert above filter:
$ echo '!write*:mod:ext3' >> /sys/kernel/tracing/set_ftrace_filter
3. Read the file:
$ cat /sys/kernel/tracing/set_ftrace_filter
By some debugging, I found that flag FTRACE_HASH_FL_MOD was not unset
after inversion like above step 2 and then result of ftrace_hash_empty()
is incorrect.
Link: https://lkml.kernel.org/r/20220926152008.2239274-1-zhengyejian1@huawei.com
Cc: <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 8c08f0d5c6 ("ftrace: Have cached module filters be an active filter")
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
An unused macro reported by [-Wunused-macros].
This macro is used to access the sp in pt_regs because at that time
x86_32 can only get sp by kernel_stack_pointer(regs).
'3c88c692c287 ("x86/stackframe/32: Provide consistent pt_regs")'
This commit have unified the pt_regs and from them we can get sp from
pt_regs with regs->sp easily. Nowhere is using this macro anymore.
Refrencing pt_regs directly is more clear. Remove this macro for
code cleaning.
Link: https://lkml.kernel.org/r/20220924072629.104759-1-chenzhongjin@huawei.com
Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
It was found that some tracing functions in kernel/trace/trace.c acquire
an arch_spinlock_t with preemption and irqs enabled. An example is the
tracing_saved_cmdlines_size_read() function which intermittently causes
a "BUG: using smp_processor_id() in preemptible" warning when the LTP
read_all_proc test is run.
That can be problematic in case preemption happens after acquiring the
lock. Add the necessary preemption or interrupt disabling code in the
appropriate places before acquiring an arch_spinlock_t.
The convention here is to disable preemption for trace_cmdline_lock and
interupt for max_lock.
Link: https://lkml.kernel.org/r/20220922145622.1744826-1-longman@redhat.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: stable@vger.kernel.org
Fixes: a35873a099 ("tracing: Add conditional snapshot")
Fixes: 939c7a4f04 ("tracing: Introduce saved_cmdlines_size file")
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There is a recursive lock on the cpu_hotplug_lock.
In kernel/trace/trace_osnoise.c:<start/stop>_per_cpu_kthreads:
- start_per_cpu_kthreads calls cpus_read_lock() and if
start_kthreads returns a error it will call stop_per_cpu_kthreads.
- stop_per_cpu_kthreads then calls cpus_read_lock() again causing
deadlock.
Fix this by calling cpus_read_unlock() before calling
stop_per_cpu_kthreads. This behavior can also be seen in commit
f46b16520a ("trace/hwlat: Implement the per-cpu mode").
This error was noticed during the LTP ftrace-stress-test:
WARNING: possible recursive locking detected
--------------------------------------------
sh/275006 is trying to acquire lock:
ffffffffb02f5400 (cpu_hotplug_lock){++++}-{0:0}, at: stop_per_cpu_kthreads
but task is already holding lock:
ffffffffb02f5400 (cpu_hotplug_lock){++++}-{0:0}, at: start_per_cpu_kthreads
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(cpu_hotplug_lock);
lock(cpu_hotplug_lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
3 locks held by sh/275006:
#0: ffff8881023f0470 (sb_writers#24){.+.+}-{0:0}, at: ksys_write
#1: ffffffffb084f430 (trace_types_lock){+.+.}-{3:3}, at: rb_simple_write
#2: ffffffffb02f5400 (cpu_hotplug_lock){++++}-{0:0}, at: start_per_cpu_kthreads
Link: https://lkml.kernel.org/r/20220919144932.3064014-1-npache@redhat.com
Fixes: c8895e271f ("trace/osnoise: Support hotplug operations")
Signed-off-by: Nico Pache <npache@redhat.com>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The sparse tool complains as follows:
kernel/trace/rv/monitors/wwnr/wwnr.c:18:19:
warning: symbol 'rv_wwnr' was not declared. Should it be static?
The `rv_wwnr` symbol is not dereferenced by other extern files,
so add static qualifier for it.
So does wip module.
Link: https://lkml.kernel.org/r/20220824034357.2014202-2-zengheng4@huawei.com
Cc: <mingo@redhat.com>
Fixes: ccc319dcb4 ("rv/monitor: Add the wwnr monitor")
Fixes: 8812d21219 ("rv/monitor: Add the wip monitor skeleton created by dot2k")
Signed-off-by: Zeng Heng <zengheng4@huawei.com>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add the filter option to the event probe. This is useful if user wants
to derive a new event based on the condition of the original event.
E.g.
echo 'e:egroup/stat_runtime_4core sched/sched_stat_runtime \
runtime=$runtime:u32 if cpu < 4' >> ../dynamic_events
Then it can filter the events only on first 4 cores.
Note that the fields used for 'if' must be the fields in the original
events, not eprobe events.
Link: https://lkml.kernel.org/r/165932114513.2850673.2592206685744598080.stgit@devnote2
Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Pull ext4 fixes from Ted Ts'o:
"Regression and bug fixes:
- Performance regression fix from 5.18 on a Rasberry Pi
- Fix extent parsing bug which triggers a BUG_ON when a (corrupted)
extent tree has has a non-root node when zero entries.
- Fix a livelock where in the right (wrong) circumstances a large
number of nfsd threads can try to write to a nearly full file
system, and retry for hours(!)"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: limit the number of retries after discarding preallocations blocks
ext4: fix bug in extents parsing when eh_entries == 0 and eh_depth > 0
ext4: use buckets for cr 1 block scan instead of rbtree
ext4: use locality group preallocation for small closed files
ext4: make directory inode spreading reflect flexbg size
ext4: avoid unnecessary spreading of allocations among groups
ext4: make mballoc try target group first even with mb_optimize_scan
Pull NVDIMM and DAX fixes from Dan Williams:
"A recently discovered one-line fix for devdax that further addresses a
v5.5 regression, and (a bit embarrassing) a small batch of fixes that
have been sitting in my fixes tree for weeks.
The older fixes have soaked in linux-next during that time and address
an fsdax infinite loop and some other minor fixups.
- Fix a infinite loop bug in fsdax
- Fix memory-type detection for devdax (EINJ regression)
- Small cleanups"
* tag 'dax-and-nvdimm-fixes-v6.0-final' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
devdax: Fix soft-reservation memory description
fsdax: Fix infinite loop in dax_iomap_rw()
nvdimm/namespace: drop nested variable in create_namespace_pmem()
ndtest: Cleanup all of blk namespace specific code
pmem: fix a name collision
Pull i2c fixes from Wolfram Sang:
"I2C driver bugfixes for mlxbf and imx, a few documentation fixes after
the rework this cycle, and one hardening for the i2c-mux core"
* tag 'i2c-for-6.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: mux: harden i2c_mux_alloc() against integer overflows
i2c: mlxbf: Fix frequency calculation
i2c: mlxbf: prevent stack overflow in mlxbf_i2c_smbus_start_transaction()
i2c: mlxbf: incorrect base address passed during io write
Documentation: i2c: fix references to other documents
MAINTAINERS: remove Nehal Shah from AMD MP2 I2C DRIVER
i2c: imx: If pm_runtime_get_sync() returned 1 device access is possible
The "hmem" platform-devices that are created to represent the
platform-advertised "Soft Reserved" memory ranges end up inserting a
resource that causes the iomem_resource tree to look like this:
340000000-43fffffff : hmem.0
340000000-43fffffff : Soft Reserved
340000000-43fffffff : dax0.0
This is because insert_resource() reparents ranges when they completely
intersect an existing range.
This matters because code that uses region_intersects() to scan for a
given IORES_DESC will only check that top-level 'hmem.0' resource and
not the 'Soft Reserved' descendant.
So, to support EINJ (via einj_error_inject()) to inject errors into
memory hosted by a dax-device, be sure to describe the memory as
IORES_DESC_SOFT_RESERVED. This is a follow-on to:
commit b13a3e5fd4 ("ACPI: APEI: Fix _EINJ vs EFI_MEMORY_SP")
...that fixed EINJ support for "Soft Reserved" ranges in the first
instance.
Fixes: 262b45ae3a ("x86/efi: EFI soft reservation to E820 enumeration")
Reported-by: Ricardo Sandoval Torres <ricardo.sandoval.torres@intel.com>
Tested-by: Ricardo Sandoval Torres <ricardo.sandoval.torres@intel.com>
Cc: <stable@vger.kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Omar Avelar <omar.avelar@intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Mark Gross <markgross@kernel.org>
Link: https://lore.kernel.org/r/166397075670.389916.7435722208896316387.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull Kbuild fixes from Masahiro Yamada:
- Fix build error for the combination of SYSTEM_TRUSTED_KEYRING=y and
X509_CERTIFICATE_PARSER=m
- Fix DEBUG_INFO_SPLIT to generate debug info for GCC 11+ and Clang 12+
- Revive debug info for assembly files
- Remove unused code
* tag 'kbuild-fixes-v6.0-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
Makefile.debug: re-enable debug info for .S files
Makefile.debug: set -g unconditional on CONFIG_DEBUG_INFO_SPLIT
certs: make system keyring depend on built-in x509 parser
Kconfig: remove unused function 'menu_get_root_menu'
scripts/clang-tools: remove unused module
Pull s390 fix from Vasily Gorbik:
- Fix potential hangs in VFIO AP driver
* tag 's390-6.0-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/vfio-ap: bypass unnecessary processing of AP resources
Pull power management fixes from Rafael Wysocki:
"These fix an uninitialized variable usage in the operating performance
points code and add missing DT bindings for it.
Specifics:
- Fix uninitialized variable usage in dev_pm_opp_config_clks_simple()
(Christophe JAILLET)
- Add missing OPP DT properties (Rob Herring)"
* tag 'pm-6.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
dt-bindings: opp: Add missing (unevaluated|additional)Properties on child nodes
OPP: Fix an un-initialized variable usage
Pull char/misc driver fixes from Greg KH:
"Here are three tiny driver fixes for 6.0-rc7. They include:
- phy driver reset bugfix
- fpga memleak bugfix
- counter irq config bugfix
The first two have been in linux-next for a while, the last one has
only been added to my tree in the past few days, but was in linux-next
under a different commit id. I couldn't pull directly from the counter
tree due to some gpg key propagation issue, so I took the commit
directly from email instead"
* tag 'char-misc-6.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
counter: 104-quad-8: Fix skipped IRQ lines during events configuration
fpga: m10bmc-sec: Fix possible memory leak of flash_buf
phy: marvell: phy-mvebu-a3700-comphy: Remove broken reset support
Pull tty/serial driver fixes from Greg KH:
"Here are some small, and late, serial driver fixes for 6.0-rc7 to
resolve some reported problems.
Included in here are:
- tegra icount accounting fixes, including a framework function that
other drivers will be converted over to using in 6.1-rc1.
- fsl_lpuart reset bugfix
- 8250 omap 485 bugfix
- sifive serial clock bugfix
The last three patches have not shown up in linux-next due to them
being added to my tree only 2 days ago, but they are tiny and
self-contained and the developers say they resolve issues that they
have with 6.0-rc. The other three have been in linux-next for a while
with no reported issues"
* tag 'tty-6.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: sifive: enable clocks for UART when probed
serial: 8250: omap: Use serial8250_em485_supported
serial: fsl_lpuart: Reset prior to registration
serial: tegra-tcu: Use uart_xmit_advance(), fixes icount.tx accounting
serial: tegra: Use uart_xmit_advance(), fixes icount.tx accounting
serial: Create uart_xmit_advance()
Pull cgroup fixes from Tejun Heo:
- Add Waiman Long as a cpuset maintainer
- cgroup_get_from_id() could be fed a kernfs ID which doesn't point to
a cgroup directory but a knob file and then crash. Error out if the
lookup kernfs_node isn't a directory.
* tag 'cgroup-for-6.0-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: cgroup_get_from_id() must check the looked-up kn is a directory
cpuset: Add Waiman Long as a cpuset maintainer
Pull workqueue fix from Tejun Heo:
"Just one patch to improve flush lockdep coverage"
* tag 'wq-for-6.0-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: don't skip lockdep work dependency in cancel_work_sync()
Pull io_uring fix from Jens Axboe:
"Just a single fix for an issue with un-reaped IOPOLL requests on ring
exit"
* tag 'io_uring-6.0-2022-09-23' of git://git.kernel.dk/linux:
io_uring: ensure that cached task references are always put on exit
Pull block fixes from Jens Axboe:
"Fix a regression that's been plaguing us by reverting the offending
commit, as attempts to both reproduce the issue and fix it in a saner
fashion have failed.
Fix for a potential oops condition in the s390 dasd block driver"
* tag 'block-6.0-2022-09-22' of git://git.kernel.dk/linux:
Revert "block: freeze the queue earlier in del_gendisk"
s390/dasd: fix Oops in dasd_alias_get_start_dev due to missing pavgroup
io_uring caches task references to avoid doing atomics for each of them
per request. If a request is put from the same task that allocated it,
then we can maintain a per-ctx cache of them. This obviously relies
on io_uring always pruning caches in a reliable way, and there's
currently a case off io_uring fd release where we can miss that.
One example is a ring setup with IOPOLL, which relies on the task
polling for completions, which will free them. However, if such a task
submits a request and then exits or closes the ring without reaping
the completion, then ring release will reap and put. If release happens
from that very same task, the completed request task refs will get
put back into the cache pool. This is problematic, as we're now beyond
the point of pruning caches.
Manually drop these caches after doing an IOPOLL reap. This releases
references from the current task, which is enough. If another task
happens to be doing the release, then the caching will not be
triggered and there's no issue.
Cc: stable@vger.kernel.org
Fixes: e98e49b2bb ("io_uring: extend task put optimisations")
Reported-by: Homin Rhee <hominlab@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull arm64 fixes from Will Deacon:
"These are all very simple and self-contained, although the CFI
jump-table fix touches the generic linker script as that's where the
problematic macro lives.
- Fix false positive "sleeping while atomic" warning resulting from
the kPTI rework taking a mutex too early.
- Fix possible overflow in AMU frequency calculation
- Fix incorrect shift in CMN PMU driver which causes problems with
newer versions of the IP
- Reduce alignment of the CFI jump table to avoid huge kernel images
and link errors with !4KiB page size configurations"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
vmlinux.lds.h: CFI: Reduce alignment of jump-table to function alignment
perf/arm-cmn: Add more bits to child node address offset field
arm64: topology: fix possible overflow in amu_fie_setup()
arm64: mm: don't acquire mutex when rewriting swapper
