================================================================== BUG: KCSAN: data-race in do_epoll_ctl / do_epoll_ctl read-write to 0xffffffff883159e8 of 8 bytes by task 12917 on cpu 1: do_epoll_ctl+0x41a/0x1c10 fs/eventpoll.c:2191 __do_sys_epoll_ctl fs/eventpoll.c:2281 [inline] __se_sys_epoll_ctl fs/eventpoll.c:2272 [inline] __x64_sys_epoll_ctl+0xb3/0xe0 fs/eventpoll.c:2272 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffffffff883159e8 of 8 bytes by task 12916 on cpu 0: do_epoll_ctl+0x367/0x1c10 fs/eventpoll.c:2185 __do_sys_epoll_ctl fs/eventpoll.c:2281 [inline] __se_sys_epoll_ctl fs/eventpoll.c:2272 [inline] __x64_sys_epoll_ctl+0xb3/0xe0 fs/eventpoll.c:2272 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 12916 Comm: systemd-udevd Not tainted 5.10.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ================================================================== Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 12916 Comm: systemd-udevd Not tainted 5.10.0-rc4-syzkaller #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+0x116/0x15d lib/dump_stack.c:118 panic+0x1e7/0x5fa kernel/panic.c:231 kcsan_report+0x67b/0x680 kernel/kcsan/report.c:634 kcsan_setup_watchpoint+0x46a/0x4d0 kernel/kcsan/core.c:568 do_epoll_ctl+0x367/0x1c10 fs/eventpoll.c:2185 __do_sys_epoll_ctl fs/eventpoll.c:2281 [inline] __se_sys_epoll_ctl fs/eventpoll.c:2272 [inline] __x64_sys_epoll_ctl+0xb3/0xe0 fs/eventpoll.c:2272 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f4c9156b2aa Code: 48 8b 0d f1 fb 2a 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 e9 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d be fb 2a 00 f7 d8 64 89 01 48 RSP: 002b:00007ffc55baaab8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9 RAX: ffffffffffffffda RBX: 00007ffc55baabb0 RCX: 00007f4c9156b2aa RDX: 000000000000000e RSI: 0000000000000001 RDI: 0000000000000004 RBP: 0000563a0bb07028 R08: 0000000000000020 R09: 0000000000000018 R10: 00007ffc55baab64 R11: 0000000000000246 R12: 0000563a0bb07010 R13: 0000563a0bb080c0 R14: 0000000000000003 R15: 000000000000000e Kernel Offset: disabled Rebooting in 86400 seconds..