syzbot


WARNING: suspicious RCU usage in kernel_execve

Status: fixed on 2021/11/10 00:50
Subsystems: fs mm
[Documentation on labels]
Fix commit: 3066820034b5 rcu: Reject RCU_LOCKDEP_WARN() false positives
First crash: 1034d, last: 1034d

Sample crash report:
=============================
WARNING: suspicious RCU usage
5.13.0-rc7-syzkaller #0 Not tainted
-----------------------------
kernel/sched/core.c:8303 Illegal context switch in RCU-sched read-side critical section!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 0
no locks held by kworker/u4:5/10304.

stack backtrace:
CPU: 1 PID: 10304 Comm: kworker/u4:5 Not tainted 5.13.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x141/0x1d7 lib/dump_stack.c:120
 ___might_sleep+0x266/0x2c0 kernel/sched/core.c:8303
 copy_strings_kernel+0x76/0x180 fs/exec.c:658
 kernel_execve+0x2fd/0x460 fs/exec.c:1965
 call_usermodehelper_exec_async+0x2e3/0x580 kernel/umh.c:112
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/06/26 06:41 upstream b7050b242430 9d2ab5df .config console log report info ci-upstream-kasan-gce WARNING: suspicious RCU usage in kernel_execve
* Struck through repros no longer work on HEAD.