BUG: unable to handle page fault for address: fffffc0000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 430 Comm: io_uring-sq Not tainted 5.4.161-syzkaller-00026-g8a3679a75730 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:91 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:108 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:134 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:165 [inline] RIP: 0010:check_memory_region_inline mm/kasan/generic.c:181 [inline] RIP: 0010:check_memory_region+0x70/0x2e0 mm/kasan/generic.c:191 Code: bd 01 00 00 00 00 fc ff df 4d 01 ea 4d 89 d6 4d 29 ce 49 83 fe 10 7f 2c 4d 85 f6 0f 84 aa 01 00 00 4c 89 cb 4c 29 d3 0f 1f 00 <45> 0f b6 19 45 84 db 0f 85 f3 01 00 00 49 ff c1 48 ff c3 75 eb e9 RSP: 0018:ffff8881e866fc30 EFLAGS: 00010006 RAX: 1ffff1103ebf8b01 RBX: 1fffffffffffffff RCX: ffffffff8424284d RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffffffffffff RBP: 1ffff1103d0cdf8c R08: dffffc0000000000 R09: fffffc0000000000 R10: dffffc0000000001 R11: 0000000000000000 R12: 1fffffffffffffff R13: dffffc0000000001 R14: e000000000000002 R15: ffff8881e866fc60 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: fffffc0000000000 CR3: 00000001ea48a000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:693 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock_flags include/linux/spinlock.h:193 [inline] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irqsave+0x8d/0x190 kernel/locking/spinlock.c:159 eventfd_signal+0x49/0x130 fs/eventfd.c:76 io_submit_sqes fs/io_uring.c:2776 [inline] io_sq_thread+0xc66/0x1990 fs/io_uring.c:2902 kthread+0x30f/0x330 kernel/kthread.c:288 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Modules linked in: CR2: fffffc0000000000 ---[ end trace 068da0eab51aac91 ]--- RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:91 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:108 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:134 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:165 [inline] RIP: 0010:check_memory_region_inline mm/kasan/generic.c:181 [inline] RIP: 0010:check_memory_region+0x70/0x2e0 mm/kasan/generic.c:191 Code: bd 01 00 00 00 00 fc ff df 4d 01 ea 4d 89 d6 4d 29 ce 49 83 fe 10 7f 2c 4d 85 f6 0f 84 aa 01 00 00 4c 89 cb 4c 29 d3 0f 1f 00 <45> 0f b6 19 45 84 db 0f 85 f3 01 00 00 49 ff c1 48 ff c3 75 eb e9 RSP: 0018:ffff8881e866fc30 EFLAGS: 00010006 RAX: 1ffff1103ebf8b01 RBX: 1fffffffffffffff RCX: ffffffff8424284d RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffffffffffff RBP: 1ffff1103d0cdf8c R08: dffffc0000000000 R09: fffffc0000000000 R10: dffffc0000000001 R11: 0000000000000000 R12: 1fffffffffffffff R13: dffffc0000000001 R14: e000000000000002 R15: ffff8881e866fc60 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: fffffc0000000000 CR3: 00000001ea48a000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: bd 01 00 00 00 mov $0x1,%ebp 5: 00 fc add %bh,%ah 7: ff (bad) 8: df 4d 01 fisttps 0x1(%rbp) b: ea (bad) c: 4d 89 d6 mov %r10,%r14 f: 4d 29 ce sub %r9,%r14 12: 49 83 fe 10 cmp $0x10,%r14 16: 7f 2c jg 0x44 18: 4d 85 f6 test %r14,%r14 1b: 0f 84 aa 01 00 00 je 0x1cb 21: 4c 89 cb mov %r9,%rbx 24: 4c 29 d3 sub %r10,%rbx 27: 0f 1f 00 nopl (%rax) * 2a: 45 0f b6 19 movzbl (%r9),%r11d <-- trapping instruction 2e: 45 84 db test %r11b,%r11b 31: 0f 85 f3 01 00 00 jne 0x22a 37: 49 ff c1 inc %r9 3a: 48 ff c3 inc %rbx 3d: 75 eb jne 0x2a 3f: e9 .byte 0xe9