Xiao Yang 8331e90cfe tracing: Fix the race between registering 'snapshot' event trigger and triggering 'snapshot' operation ...

commit 0bbe7f7199 upstream.

Traced event can trigger 'snapshot' operation(i.e. calls snapshot_trigger()
or snapshot_count_trigger()) when register_snapshot_trigger() has completed
registration but doesn't allocate buffer for 'snapshot' event trigger.  In
the rare case, 'snapshot' operation always detects the lack of allocated
buffer so make register_snapshot_trigger() allocate buffer first.

trigger-snapshot.tc in kselftest reproduces the issue on slow vm:
-----------------------------------------------------------
cat trace
...
ftracetest-3028  [002] ....   236.784290: sched_process_fork: comm=ftracetest pid=3028 child_comm=ftracetest child_pid=3036
     <...>-2875  [003] ....   240.460335: tracing_snapshot_instance_cond: *** SNAPSHOT NOT ALLOCATED ***
     <...>-2875  [003] ....   240.460338: tracing_snapshot_instance_cond: *** stopping trace here!   ***
-----------------------------------------------------------

Link: http://lkml.kernel.org/r/20200414015145.66236-1-yangx.jy@cn.fujitsu.com

Cc: stable@vger.kernel.org
Fixes: 93e31ffbf4 ("tracing: Add 'snapshot' event trigger command")
Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2023-05-15 17:15:39 +09:00

..

bpf

bpf: Explicitly memset the bpf_attr structure

2023-05-15 17:12:39 +09:00

configs

ANDROID: add script to fetch android kernel config fragments

2017-10-03 17:19:26 +00:00

debug

kdb: do a sanity check on the cpu in kdb_per_cpu()

2023-05-15 16:45:22 +09:00

events

perf/core: Fix mlock accounting in perf_mmap()

2023-05-15 16:57:01 +09:00

gcov

gcov: support GCC 7.1

2017-09-02 07:07:53 +02:00

irq

genirq: Fix reference leaks on irq affinity notifiers

2023-05-15 17:11:48 +09:00

livepatch

livepatch/module: make TAINT_LIVEPATCH module-specific

2016-08-26 14:42:08 +02:00

locking

locking/lockdep: Avoid recursion in lockdep_count_{for,back}ward_deps()

2023-05-15 17:13:57 +09:00

power

PM / hibernate: memory_bm_find_bit(): Tighten node optimisation

2023-05-15 16:30:12 +09:00

printk

printk: fix integer overflow in setup_log_buf()

2023-05-15 15:17:10 +09:00

rcu

rcuperf: Fix cleanup path for invalid perf_type strings

2023-05-15 13:36:07 +09:00

sched

sched: Avoid scale real weight down to zero

2023-05-15 17:13:50 +09:00

time

clocksource: Prevent double add_timer_on() for watchdog_timer

2023-05-15 16:57:00 +09:00

trace

tracing: Fix the race between registering 'snapshot' event trigger and triggering 'snapshot' operation

2023-05-15 17:15:39 +09:00

.gitignore

certs: add .gitignore to stop git nagging about x509_certificate_list

2015-10-21 15:18:35 +01:00

acct.c

kernel/acct.c: fix the acct->needcheck check in check_free_space()

2018-01-10 09:29:51 +01:00

async.c

kernel/async.c: revert "async: simplify lowest_in_progress()"

2018-02-17 13:21:18 +01:00

audit_fsnotify.c

wrappers for ->i_mutex access

2016-01-22 18:04:28 -05:00

audit_tree.c

audit: cleanup prune_tree_thread

2016-04-04 09:46:47 -04:00

audit_watch.c

audit_get_nd(): don't unlock parent too early

2023-05-15 16:08:52 +09:00

audit.c

audit: always check the netlink payload length in audit_receive_msg()

2023-05-15 17:02:10 +09:00

audit.h

Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit

2016-07-29 17:54:17 -07:00

auditfilter.c

audit: fix error handling in audit_data_to_entry()

2023-05-15 17:01:41 +09:00

auditsc.c

audit: print empty EXECVE args

2023-05-15 15:18:40 +09:00

backtracetest.c

…

bounds.c

kbuild: fix kernel/bounds.c 'W=1' warning

2023-05-15 09:22:43 +09:00

capability.c

ptrace: Capture the ptracer's creds not PT_PTRACE_CAP

2017-01-06 10:40:13 +01:00

cfi.c

cfi: print target address on failure

2018-05-01 16:49:34 +00:00

cgroup_freezer.c

cgroup: kill cgrp_ss_priv[CGROUP_CANFORK_COUNT] and friends

2015-12-03 10:24:08 -05:00

cgroup_pids.c

cgroup: pids: use atomic64_t for pids->limit

2023-05-15 16:16:25 +09:00

cgroup.c

cgroup: memcg: net: do not associate sock with unrelated cgroup

2023-05-15 17:09:20 +09:00

compat.c

19af5c5 dtv_demod: add AGC control for board t309 [1/1]

2019-05-06 21:14:10 +08:00

configs.c

…

context_tracking.c

context_tracking: Switch to new static_branch API

2015-11-24 09:56:43 +01:00

cpu_pm.c

kernel/cpu_pm: fix cpu_cluster_pm_exit comment

2015-09-03 02:42:20 +02:00

cpu.c

x86/speculation: Remove redundant arch_smt_update() invocation

2023-05-15 17:14:41 +09:00

cpuset.c

Merge 4.9.55 into android-4.9

2017-10-12 22:31:24 +02:00

crash_dump.c

crash_dump: Make is_kdump_kernel() accessible from modules

2014-08-25 15:42:19 -07:00

cred.c

memcg: account security cred as well to kmemcg

2023-05-15 16:30:24 +09:00

delayacct.c

kmemcg: account certain kmem allocations to memcg

2016-01-14 16:00:49 -08:00

dma.c

…

elfcore.c

kernel/elfcore.c: include proper prototypes

2023-05-15 14:48:01 +09:00

exec_domain.c

Remove rest of exec domains.

2015-04-12 21:03:31 +02:00

exit.c

kernel/exit.c: release ptraced tasks before zap_pid_ns_processes

2023-05-15 11:16:37 +09:00

extable.c

kernel/extable.c: mark core_kernel_text notrace

2017-07-21 07:42:21 +02:00

fork.c

kernel/sysctl.c: do not override max_threads provided by userspace

2023-05-15 14:49:35 +09:00

freezer.c

freezer, oom: check TIF_MEMDIE on the correct task

2016-07-28 16:07:41 -07:00

futex_compat.c

ptrace: use fsuid, fsgid, effective creds for fs access checks

2016-01-20 17:09:18 -08:00

futex.c

futex: Unbreak futex hashing

2023-05-15 17:11:11 +09:00

groups.c

kernel: make groups_sort calling a responsibility group_info allocators

2018-01-10 09:29:52 +01:00

hung_task.c

kernel: hung_task.c: disable on suspend

2023-05-15 12:23:14 +09:00

irq_work.c

treewide: Remove old email address

2015-11-23 09:44:58 +01:00

jump_label.c

jump_label: Invoke jump_label_test() via early_initcall()

2017-12-14 09:28:24 +01:00

kallsyms.c

rodata: optimize memory usage of rodata section [4/5]

2023-04-21 13:52:34 +09:00

kcmp.c

ptrace: use fsuid, fsgid, effective creds for fs access checks

2016-01-20 17:09:18 -08:00

Kconfig.freezer

…

Kconfig.hz

…

Kconfig.locks

locking/qrwlock: Rename QUEUE_RWLOCK to QUEUED_RWLOCKS

2015-05-12 09:46:00 +02:00

Kconfig.preempt

…

kcov.c

kcov: ensure irq code sees a valid area

2023-05-12 16:39:07 +09:00

kexec_core.c

objtool, x86: Add several functions and files to the objtool whitelist

2018-06-05 10:28:57 +02:00

kexec_file.c

kexec: fix double-free when failing to relocate the purgatory

2016-09-01 17:52:01 -07:00

kexec_internal.h

kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE

2016-01-20 17:09:18 -08:00

kexec.c

kexec: allow architectures to override boot mapping

2016-08-02 19:35:27 -04:00

kmod.c

kmod: make request_module() return an error when autoloading is disabled

2023-05-15 17:14:56 +09:00

kprobes.c

kprobes: Don't call BUG_ON() if there is a kprobe in use on free list

2023-05-15 15:08:53 +09:00

ksysfs.c

kexec: add a kexec_crash_loaded() function

2016-08-02 19:35:30 -04:00

kthread.c

kthread, tracing: Don't expose half-written comm when creating kthreads

2023-05-12 16:38:55 +09:00

latencytop.c

sched/debug: Make schedstats a runtime tunable that is disabled by default

2016-02-09 11:54:23 +01:00

Makefile

x86/uaccess, kcov: Disable stack protector

2023-05-15 13:48:54 +09:00

membarrier.c

Fix: Disable sys_membarrier when nohz_full is enabled

2017-03-12 06:41:45 +01:00

memremap.c

mm, devm_memremap_pages: kill mapping "System RAM" support

2023-05-15 10:54:41 +09:00

module_signing.c

KEYS: Move the point of trust determination to __key_link()

2016-04-11 22:43:43 +01:00

module-internal.h

…

module.c

kernel/module.c: wakeup processes in module_wq on module unload

2023-05-15 16:17:28 +09:00

notifier.c

x86/mm: split vmalloc_sync_all()

2023-05-15 17:11:06 +09:00

nsproxy.c

cgroup: introduce cgroup namespaces

2016-02-16 13:04:58 -05:00

padata.c

padata: always acquire cpu_hotplug_lock before pinst->lock

2023-05-15 17:13:03 +09:00

panic.c

panic: ensure preemption is disabled during panic()

2023-05-15 14:48:19 +09:00

params.c

Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

2015-11-09 15:53:39 -08:00

pid_namespace.c

signal/pid_namespace: Fix reboot_pid_ns to use send_sig not force_sig

2023-05-15 13:59:49 +09:00

pid.c

pidns: disable pid allocation if pid_ns_prepare_proc() is failed in alloc_pid()

2018-04-13 19:47:53 +02:00

profile.c

profile: Convert to hotplug state machine

2016-07-15 10:41:42 +02:00

ptrace.c

ptrace: Fix ->ptracer_cred handling for PTRACE_TRACEME

2023-05-15 13:57:11 +09:00

range.c

kernel: avoid overflow in cmp_range

2015-01-17 10:02:23 +13:00

reboot.c

kexec: split kexec_load syscall from kexec core code

2015-09-10 13:29:01 -07:00

relay.c

kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE

2018-05-30 07:50:29 +02:00

resource.c

resource: fix integer overflow at reallocation

2018-04-24 09:34:09 +02:00

seccomp.c

seccomp: Move speculation migitation control to arch code

2018-05-22 16:58:02 +02:00

signal.c

signal: Extend exec_id to 64bits

2023-05-15 17:14:27 +09:00

smp.c

cpu/hotplug: Fix SMT supported evaluation

2023-05-12 16:55:46 +09:00

smpboot.c

kthread/smpboot: do not park in kthread_create_on_cpu()

2016-10-11 15:06:33 -07:00

smpboot.h

cpu/hotplug: Create hotplug threads

2016-03-01 20:36:56 +01:00

softirq.c

Mark HI and TASKLET softirq synchronous

2023-05-12 16:46:40 +09:00

stacktrace.c

stacktrace, lockdep: Fix address, newline ugliness

2017-02-14 15:25:42 -08:00

stop_machine.c

stop_machine: Use raw spinlocks

2023-05-12 16:43:35 +09:00

sys_ni.c

x86/pkeys: Fix pkeys build breakage for some non-x86 arches

2016-09-13 14:41:36 +02:00

sys.c

kernel/sys.c: prctl: fix false positive in validate_prctl_map()

2023-05-15 13:47:18 +09:00

sysctl_binary.c

kernel/sysctl_binary.c: use generic UUID library

2016-05-20 17:58:30 -07:00

sysctl.c

kernel: sysctl: make drop_caches write-only

2023-05-15 16:21:29 +09:00

task_work.c

task_work: use READ_ONCE/lockless_dereference, avoid pi_lock if !task_works

2016-08-02 19:35:02 -04:00

taskstats.c

taskstats: fix data-race

2023-05-15 16:30:15 +09:00

test_kprobes.c

kernel/test_kprobes.c: use current logging functions

2014-08-08 15:57:18 -07:00

torture.c

torture: Convert torture_shutdown() to hrtimer

2016-08-22 10:01:49 -07:00

tracepoint.c

tracepoint: Do not warn on ENOMEM

2018-05-09 09:50:20 +02:00

tsacct.c

time, acct: Drop irq save & restore from __acct_update_integrals()

2016-02-29 09:53:09 +01:00

ucount.c

kernel/ucount.c: mark user_header with kmemleak_ignore()

2017-06-17 06:41:51 +02:00

uid16.c

kernel: make groups_sort calling a responsibility group_info allocators

2018-01-10 09:29:52 +01:00

up.c

smp: Add function to execute a function synchronously on a CPU

2016-09-05 13:52:39 +02:00

user_namespace.c

userns: move user access out of the mutex

2023-05-12 17:24:22 +09:00

user-return-notifier.c

scheduler: Replace __get_cpu_var with this_cpu_ptr

2014-08-26 13:45:45 -04:00

user.c

ANDROID: proc: Add /proc/uid directory

2018-04-03 11:15:30 -07:00

utsname_sysctl.c

sys: don't hold uts_sem while accessing userspace memory

2023-05-12 17:24:20 +09:00

utsname.c

Merge branch 'nsfs-ioctls' into HEAD

2016-09-22 20:00:36 -05:00

watchdog_hld.c

debug: hard lockup detect

2018-05-09 19:39:28 -07:00

watchdog.c

debug: hard lockup detect

2018-05-09 19:39:28 -07:00

workqueue_internal.h

workqueue: Fix NULL pointer dereference

2017-11-15 15:53:17 +01:00

workqueue.c

workqueue: don't use wq_select_unbound_cpu() for bound works

2023-05-15 17:09:24 +09:00