linux/kernel
Steven Rostedt (VMware) b40341fad6 ftrace: Move RCU is watching check after recursion check
The first thing that the ftrace function callback helper functions should do
is to check for recursion. Peter Zijlstra found that when
"rcu_is_watching()" had its notrace removed, it caused perf function tracing
to crash. This is because the call of rcu_is_watching() is tested before
function recursion is checked and and if it is traced, it will cause an
infinite recursion loop.

rcu_is_watching() should still stay notrace, but to prevent this should
never had crashed in the first place. The recursion prevention must be the
first thing done in callback functions.

Link: https://lore.kernel.org/r/20200929112541.GM2628@hirez.programming.kicks-ass.net

Cc: stable@vger.kernel.org
Cc: Paul McKenney <paulmck@kernel.org>
Fixes: c68c0fa293 ("ftrace: Have ftrace_ops_get_func() handle RCU and PER_CPU flags too")
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-29 13:05:10 -04:00
..
bpf Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-03 18:50:48 -07:00
cgroup for-5.9/block-20200802 2020-08-03 11:57:03 -07:00
configs compiler: remove CONFIG_OPTIMIZE_INLINING entirely 2020-04-07 10:43:42 -07:00
debug treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
dma dma-pool: Fix an uninitialized variable bug in atomic_pool_expand() 2020-08-27 09:22:56 +02:00
entry x86/entry: Unbreak 32bit fast syscall 2020-09-04 15:50:14 +02:00
events treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
gcov gcov: add support for GCC 10.1 2020-09-11 09:33:54 -07:00
irq Three interrupt related fixes for X86: 2020-08-30 12:01:23 -07:00
kcsan Merge branch 'kcsan' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/core 2020-08-01 09:26:27 +02:00
livepatch livepatch: Make klp_apply_object_relocs static 2020-05-11 00:31:38 +02:00
locking lockdep,trace: Expose tracepoints 2020-08-26 12:41:56 +02:00
power treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
printk Printk changes for 5.9 2020-08-04 22:22:25 -07:00
rcu rcu: kasan: record and print call_rcu() call stack 2020-08-07 11:33:28 -07:00
sched A set of fixes for lockdep, tracing and RCU: 2020-08-30 11:43:50 -07:00
time treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
trace ftrace: Move RCU is watching check after recursion check 2020-09-29 13:05:10 -04:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
Makefile all arch: remove system call sys_sysctl 2020-08-14 19:56:56 -07:00
acct.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
async.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
audit.c audit/stable-5.9 PR 20200803 2020-08-04 14:20:26 -07:00
audit.h revert: 1320a4052e ("audit: trigger accompanying records when no rules present") 2020-07-29 10:00:36 -04:00
audit_fsnotify.c fsnotify: create method handle_inode_event() in fsnotify_operations 2020-07-27 23:25:50 +02:00
audit_tree.c \n 2020-08-06 19:29:51 -07:00
audit_watch.c fsnotify: create method handle_inode_event() in fsnotify_operations 2020-07-27 23:25:50 +02:00
auditfilter.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
auditsc.c audit/stable-5.9 PR 20200803 2020-08-04 14:20:26 -07:00
backtracetest.c treewide: Replace DECLARE_TASKLET() with DECLARE_TASKLET_OLD() 2020-07-30 11:15:58 -07:00
bounds.c
capability.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
compat.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
configs.c
context_tracking.c context_tracking: Ensure that the critical path cannot be instrumented 2020-06-11 15:14:36 +02:00
cpu.c The changes in this cycle are: 2020-06-03 13:06:42 -07:00
cpu_pm.c kernel/cpu_pm: Fix uninitted local in cpu_pm 2020-05-15 11:44:34 -07:00
crash_core.c kdump: append kernel build-id string to VMCOREINFO 2020-08-12 10:58:01 -07:00
crash_dump.c crash_dump: Remove no longer used saved_max_pfn 2020-04-15 11:21:54 +02:00
cred.c exec: Teach prepare_exec_creds how exec treats uids & gids 2020-05-20 14:44:21 -05:00
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c kernel: add a kernel_wait helper 2020-08-12 10:57:59 -07:00
extable.c kernel/extable.c: use address-of operator on section symbols 2020-04-07 10:43:42 -07:00
fail_function.c
fork.c fork: adjust sysctl_max_threads definition to match prototype 2020-09-05 12:14:29 -07:00
freezer.c
futex.c futex: Convert to use the preferred 'fallthrough' macro 2020-08-13 21:02:12 +02:00
gen_kheaders.sh kbuild: add variables for compression tools 2020-06-06 23:42:01 +09:00
groups.c mm: remove the pgprot argument to __vmalloc 2020-06-02 10:59:11 -07:00
hung_task.c kernel/hung_task.c: introduce sysctl to print all traces when a hung task is detected 2020-06-08 11:05:56 -07:00
iomem.c
irq_work.c irq_work, smp: Allow irq_work on call_single_queue 2020-05-28 10:54:15 +02:00
jump_label.c
kallsyms.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
kcmp.c kernel/kcmp.c: Use new infrastructure to fix deadlocks in execve 2020-03-25 10:04:01 -05:00
kcov.c kcov: make some symbols static 2020-08-12 10:58:02 -07:00
kexec.c
kexec_core.c
kexec_elf.c
kexec_file.c Misc fixes and small updates all around the place: 2020-08-15 10:38:03 -07:00
kexec_internal.h
kheaders.c
kmod.c kmod: remove redundant "be an" in the comment 2020-08-12 10:58:01 -07:00
kprobes.c kprobes: tracing/kprobes: Fix to kill kprobes on initmem after boot 2020-09-18 14:27:24 -04:00
ksysfs.c
kthread.c uaccess: add force_uaccess_{begin,end} helpers 2020-08-12 10:57:59 -07:00
latencytop.c sysctl: pass kernel pointers to ->proc_handler 2020-04-27 02:07:40 -04:00
module-internal.h
module.c Modules updates for v5.9 2020-08-14 11:07:02 -07:00
module_signature.c
module_signing.c
notifier.c mm: remove vmalloc_sync_(un)mappings() 2020-06-02 10:59:12 -07:00
nsproxy.c nsproxy: support CLONE_NEWTIME with setns() 2020-07-08 11:14:22 +02:00
padata.c padata: fix possible padata_works_lock deadlock 2020-09-04 17:51:55 +10:00
panic.c panic: make print_oops_end_marker() static 2020-08-12 10:58:02 -07:00
params.c
pid.c cap-checkpoint-restore-v5.9 2020-08-04 15:02:07 -07:00
pid_namespace.c pid_namespace: use checkpoint_restore_ns_capable() for ns_last_pid 2020-07-19 20:14:42 +02:00
profile.c
ptrace.c
range.c
reboot.c arch: remove unicore32 port 2020-07-01 12:09:13 +03:00
regset.c regset: kill ->get() 2020-07-27 14:31:12 -04:00
relay.c kernel/relay.c: fix memleak on destroy relay channel 2020-08-21 09:52:53 -07:00
resource.c /dev/mem: Revoke mappings when a driver claims the region 2020-05-27 11:10:05 +02:00
rseq.c
scs.c mm: memcontrol: account kernel stack per node 2020-08-07 11:33:25 -07:00
seccomp.c seccomp: don't leave dangling ->notif if file allocation fails 2020-09-08 11:30:16 -07:00
signal.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
smp.c smp: Fix a potential usage of stale nr_cpus 2020-07-22 10:22:04 +02:00
smpboot.c
smpboot.h
softirq.c tasklets API update for v5.9-rc1 2020-08-04 13:40:35 -07:00
stackleak.c gcc-plugins/stackleak: Use asm instrumentation to avoid useless register saving 2020-06-24 07:48:28 -07:00
stacktrace.c uaccess: add force_uaccess_{begin,end} helpers 2020-08-12 10:57:59 -07:00
stop_machine.c
sys.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
sys_ni.c all arch: remove system call sys_sysctl 2020-08-14 19:56:56 -07:00
sysctl-test.c
sysctl.c bpf, sysctl: Let bpf_stats_handler take a kernel pointer buffer 2020-08-24 21:11:40 -07:00
task_work.c task_work: only grab task signal lock when needed 2020-08-13 09:01:38 -06:00
taskstats.c
test_kprobes.c
torture.c torture: Dump ftrace at shutdown only if requested 2020-06-29 12:01:45 -07:00
tracepoint.c
tsacct.c
ucount.c ucount: Make sure ucounts in /proc/sys/user don't regress again 2020-04-07 21:51:27 +02:00
uid16.c
uid16.h
umh.c kernel: add a kernel_wait helper 2020-08-12 10:57:59 -07:00
up.c
user-return-notifier.c
user.c user.c: make uidhash_table static 2020-06-04 19:06:24 -07:00
user_namespace.c nsproxy: add struct nsset 2020-05-09 13:57:12 +02:00
usermode_driver.c umd: Stop using split_argv 2020-07-07 11:58:59 -05:00
utsname.c nsproxy: add struct nsset 2020-05-09 13:57:12 +02:00
utsname_sysctl.c sysctl: pass kernel pointers to ->proc_handler 2020-04-27 02:07:40 -04:00
watch_queue.c watch_queue: Limit the number of watches a user can hold 2020-08-17 09:39:18 -07:00
watchdog.c kernel/watchdog.c: convert {soft/hard}lockup boot parameters to sysctl aliases 2020-06-08 11:05:56 -07:00
watchdog_hld.c
workqueue.c maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
workqueue_internal.h