================================================================== BUG: KCSAN: data-race in do_nanosleep / mm_update_next_owner read to 0xffff888126f440e4 of 4 bytes by task 7501 on cpu 0: mm_update_next_owner+0x29f/0x460 kernel/exit.c:389 exit_mm kernel/exit.c:484 [inline] do_exit+0x4c1/0x18f0 kernel/exit.c:804 do_group_exit+0xb4/0x1c0 kernel/exit.c:921 get_signal+0x2a2/0x1320 kernel/signal.c:2734 do_signal+0x3b/0xc00 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x250/0x2c0 arch/x86/entry/common.c:159 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x353/0x370 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x44/0xa9 write to 0xffff888126f440e4 of 4 bytes by task 7247 on cpu 1: freezer_do_not_count include/linux/freezer.h:109 [inline] freezable_schedule include/linux/freezer.h:171 [inline] do_nanosleep+0x127/0x320 kernel/time/hrtimer.c:1871 hrtimer_nanosleep+0x191/0x320 kernel/time/hrtimer.c:1924 __do_sys_nanosleep kernel/time/hrtimer.c:1958 [inline] __se_sys_nanosleep kernel/time/hrtimer.c:1945 [inline] __x64_sys_nanosleep+0x106/0x150 kernel/time/hrtimer.c:1945 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7247 Comm: syz-executor.2 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ================================================================== Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 7247 Comm: syz-executor.2 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xf5/0x159 lib/dump_stack.c:113 panic+0x210/0x640 kernel/panic.c:221 kcsan_report.cold+0xc/0x10 kernel/kcsan/report.c:302 __kcsan_setup_watchpoint+0x32e/0x4a0 kernel/kcsan/core.c:411 __tsan_write4 kernel/kcsan/kcsan.c:35 [inline] __tsan_write4+0x32/0x40 kernel/kcsan/kcsan.c:35 freezer_do_not_count include/linux/freezer.h:109 [inline] freezable_schedule include/linux/freezer.h:171 [inline] do_nanosleep+0x127/0x320 kernel/time/hrtimer.c:1871 hrtimer_nanosleep+0x191/0x320 kernel/time/hrtimer.c:1924 __do_sys_nanosleep kernel/time/hrtimer.c:1958 [inline] __se_sys_nanosleep kernel/time/hrtimer.c:1945 [inline] __x64_sys_nanosleep+0x106/0x150 kernel/time/hrtimer.c:1945 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x457f00 Code: c0 5b 5d c3 66 0f 1f 44 00 00 8b 04 24 48 83 c4 18 5b 5d c3 66 0f 1f 44 00 00 83 3d 51 e8 61 00 00 75 14 b8 23 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 24 d3 fb ff c3 48 83 ec 08 e8 ea 46 00 00 RSP: 002b:00007fffc27baa68 EFLAGS: 00000246 ORIG_RAX: 0000000000000023 RAX: ffffffffffffffda RBX: 000000000000e8dd RCX: 0000000000457f00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007fffc27baa70 RBP: 0000000000000014 R08: 0000000000000001 R09: 0000000000b49940 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000007 R13: 00007fffc27baac0 R14: 000000000000e87f R15: 00007fffc27baad0 Kernel Offset: disabled Rebooting in 86400 seconds..