bisecting fixing commit since 2187f215ebaac73ddbd814696d7c7fa34f0c3de0
building syzkaller on 79b211f74b08737aeb4934c6ff69a263b3c38013
testing commit 2187f215ebaac73ddbd814696d7c7fa34f0c3de0 with gcc (GCC) 8.1.0
kernel signature: 615e40eda559bf8dcaaa4d5a2eb67a9276578b4748784fbecf5efb0f0425522b
run #0: crashed: INFO: rcu detected stall in corrupted
run #1: crashed: INFO: rcu detected stall in corrupted
run #2: crashed: INFO: rcu detected stall in do_signal
run #3: crashed: INFO: rcu detected stall in bad_area
run #4: crashed: INFO: rcu detected stall in lock_is_held_type
run #5: crashed: INFO: rcu detected stall in do_signal
run #6: crashed: INFO: rcu detected stall in do_signal
run #7: crashed: INFO: rcu detected stall in do_signal
run #8: crashed: INFO: rcu detected stall in bad_area
run #9: crashed: INFO: rcu detected stall in bad_area
testing current HEAD 04300d66f0a06d572d9f2ad6768c38cabde22179
testing commit 04300d66f0a06d572d9f2ad6768c38cabde22179 with gcc (GCC) 8.1.0
kernel signature: 506225a1d115b7c56b9a956ccc05abbc43d709b7f2d7a3bc9dc4f0167463ed1b
run #0: crashed: INFO: rcu detected stall in corrupted
run #1: crashed: INFO: rcu detected stall in corrupted
run #2: crashed: INFO: rcu detected stall in corrupted
run #3: crashed: INFO: rcu detected stall in corrupted
run #4: crashed: INFO: rcu detected stall in corrupted
run #5: crashed: INFO: rcu detected stall in corrupted
run #6: crashed: INFO: rcu detected stall in do_signal
run #7: crashed: INFO: rcu detected stall in corrupted
run #8: crashed: INFO: rcu detected stall in corrupted
run #9: crashed: INFO: rcu detected stall in corrupted
revisions tested: 2, total time: 24m17.484231687s (build: 12m40.722000464s, test: 10m27.745641467s)
the crash still happens on HEAD
commit msg: Merge tag 'riscv-for-linus-5.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux into master
crash: INFO: rcu detected stall in corrupted
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
	(detected by 1, t=10502 jiffies, g=3789, q=336)
rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294952879-4294942376), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10504 jiffies! g3789 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    14280    10      2 0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3458 [inline]
 __schedule+0x3fc/0x870 kernel/sched/core.c:4219
 schedule+0x3b/0xf0 kernel/sched/core.c:4294
 schedule_timeout+0x175/0x310 kernel/time/timer.c:1908
 rcu_gp_fqs_loop kernel/rcu/tree.c:1874 [inline]
 rcu_gp_kthread+0x702/0xc70 kernel/rcu/tree.c:2044
 kthread+0x160/0x180 kernel/kthread.c:291
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293