bisecting fixing commit since fc3abb53250a90ba2150eebd182137c136f4d25a
building syzkaller on abf9ba4fc75d9b29af15625d44dcfc1360fad3b7
testing commit fc3abb53250a90ba2150eebd182137c136f4d25a with gcc (GCC) 8.4.1 20210217
kernel signature: 2d171b5e99cc1e86f328ad10335be5d24c0cdee9cf72ab9f90479e8592770217
run #0: crashed: BUG: soft lockup in wb_workfn
run #1: crashed: BUG: soft lockup in tc_modify_qdisc
run #2: crashed: BUG: soft lockup in tc_modify_qdisc
run #3: crashed: BUG: soft lockup in rtnl_newlink
run #4: crashed: BUG: soft lockup in do_idle
run #5: crashed: BUG: soft lockup in do_idle
run #6: crashed: BUG: soft lockup in do_idle
run #7: crashed: BUG: workqueue lockup
run #8: crashed: BUG: soft lockup in rtnl_newlink
run #9: crashed: BUG: soft lockup in do_idle
run #10: crashed: BUG: soft lockup in wb_workfn
run #11: crashed: BUG: soft lockup in do_idle
run #12: crashed: BUG: soft lockup in mutex_spin_on_owner
run #13: crashed: BUG: soft lockup in do_idle
run #14: crashed: BUG: soft lockup in smp_call_function
run #15: crashed: BUG: soft lockup in do_idle
run #16: crashed: BUG: soft lockup in wb_workfn
run #17: crashed: BUG: soft lockup in do_idle
run #18: crashed: BUG: soft lockup in do_idle
run #19: crashed: BUG: soft lockup in do_idle
testing current HEAD dbe69e43372212527abf48609aba7fc39a6daa27
testing commit dbe69e43372212527abf48609aba7fc39a6daa27 with gcc (GCC) 10.2.1 20210217
kernel signature: c363c3e9ef6d325b8020d550976d42af03f732bd2bc987c0cef15c1000f4c59b
run #0: crashed: BUG: soft lockup in net_tx_action
run #1: crashed: BUG: soft lockup in tc_modify_qdisc
run #2: crashed: BUG: soft lockup in mutex_spin_on_owner
run #3: crashed: BUG: soft lockup in inet6_rtm_newaddr
run #4: crashed: BUG: soft lockup in rtnl_newlink
run #5: crashed: BUG: workqueue lockup
run #6: crashed: BUG: soft lockup in do_faccessat
run #7: crashed: BUG: soft lockup in net_tx_action
run #8: crashed: BUG: soft lockup in do_idle
run #9: crashed: BUG: soft lockup in do_idle
revisions tested: 2, total time: 22m27.389949092s (build: 12m21.424360221s, test: 9m15.485970062s)
the crash still happens on HEAD
commit msg: Merge tag 'net-next-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
crash: BUG: soft lockup in do_idle
watchdog: BUG: soft lockup - CPU#0 stuck for 27s! [swapper/0:0]
Modules linked in:
irq event stamp: 138154
hardirqs last  enabled at (138153): [<ffffffff87822f97>] acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline]
hardirqs last  enabled at (138153): [<ffffffff87822f97>] acpi_idle_do_entry+0x157/0x290 drivers/acpi/processor_idle.c:553
hardirqs last disabled at (138154): [<ffffffff877faccb>] sysvec_apic_timer_interrupt+0xb/0xc0 arch/x86/kernel/apic/apic.c:1100
softirqs last  enabled at (138142): [<ffffffff814202c9>] invoke_softirq kernel/softirq.c:432 [inline]
softirqs last  enabled at (138142): [<ffffffff814202c9>] __irq_exit_rcu kernel/softirq.c:636 [inline]
softirqs last  enabled at (138142): [<ffffffff814202c9>] irq_exit_rcu+0x229/0x270 kernel/softirq.c:648
softirqs last disabled at (136879): [<ffffffff814202c9>] invoke_softirq kernel/softirq.c:432 [inline]
softirqs last disabled at (136879): [<ffffffff814202c9>] __irq_exit_rcu kernel/softirq.c:636 [inline]
softirqs last disabled at (136879): [<ffffffff814202c9>] irq_exit_rcu+0x229/0x270 kernel/softirq.c:648
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:native_safe_halt+0xb/0x10 arch/x86/include/asm/irqflags.h:52
Code: e8 da 0b 25 fa e9 e7 fe ff ff 48 89 df e8 cd 0b 25 fa eb 9c cc cc cc cc cc cc cc cc cc cc cc eb 07 0f 00 2d b7 5f 66 00 fb f4 <c3> 0f 1f 40 00 eb 07 0f 00 2d a7 5f 66 00 f4 c3 cc cc cc cc cc 55
RSP: 0018:ffffffff89407d70 EFLAGS: 00000286
RAX: 1ffffffff12aeaa1 RBX: ffff88810475e065 RCX: 1ffffffff14cb131
RDX: dffffc0000000000 RSI: ffffffff87eb5e60 RDI: ffffffff8833aba0
RBP: ffffffff8949a4c0 R08: 0000000000000001 R09: 0000000000000001
R10: fffffbfff1293498 R11: 0000000000000001 R12: 0000000000000001
R13: ffffffff89c92420 R14: ffff88810475e064 R15: ffff888104d5b004
FS:  0000000000000000(0000) GS:ffff8881f6400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f79ca357000 CR3: 000000010a839000 CR4: 0000000000350ef0
Call Trace:
 arch_safe_halt arch/x86/include/asm/paravirt.h:167 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline]
 acpi_idle_do_entry+0x189/0x290 drivers/acpi/processor_idle.c:553
 acpi_idle_enter+0x2d4/0x4a0 drivers/acpi/processor_idle.c:688
 cpuidle_enter_state+0x145/0x990 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x45/0xa0 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x497/0x730 kernel/sched/idle.c:306
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
 start_kernel+0x340/0x35e init/main.c:1084
 secondary_startup_64_no_verify+0xb0/0xbb