syzbot


kernel panic: System is deadlocked on memory

Status: upstream: reported on 2026/04/28 08:51
Reported-by: syzbot+6479a2996b0d81efac5a@syzkaller.appspotmail.com
First crash: 14d, last: 14d
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream kernel panic: System is deadlocked on memory (2) mm 2 148 7d02h 637d 0/29 upstream: reported on 2024/08/12 10:54
upstream kernel panic: System is deadlocked on memory mm 2 C done 43 2129d 2127d 15/29 fixed on 2020/11/16 12:12

Sample crash report:
kmalloc-256             4859KB       5256KB
kmalloc-192             1794KB       2264KB
kmalloc-128             1645KB       2624KB
kmalloc-96               638KB       1028KB
kmalloc-64              3586KB       4012KB
kmalloc-32              1388KB       1392KB
kmalloc-16               357KB        424KB
kmalloc-8                646KB        701KB
kmem_cache_node          207KB        208KB
kmem_cache               172KB        172KB
Out of memory and no killable processes...
Kernel panic - not syncing: System is deadlocked on memory
CPU: 1 PID: 3950 Comm: sshd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 panic+0x2e5/0x810 kernel/panic.c:309
 out_of_memory+0x10ea/0x1180 mm/oom_kill.c:1150
 __alloc_pages_may_oom mm/page_alloc.c:4359 [inline]
 __alloc_pages_slowpath+0x1dc5/0x28b0 mm/page_alloc.c:5177
 __alloc_pages+0x340/0x480 mm/page_alloc.c:5514
 alloc_pages_vma+0x393/0x7c0 mm/mempolicy.c:2146
 __read_swap_cache_async+0x1b5/0xa70 mm/swap_state.c:459
 read_swap_cache_async mm/swap_state.c:525 [inline]
 swap_cluster_readahead+0x6a3/0x7c0 mm/swap_state.c:661
 swapin_readahead+0xf1/0xac0 mm/swap_state.c:854
 do_swap_page+0x4b6/0x1f40 mm/memory.c:3622
 handle_pte_fault mm/memory.c:4654 [inline]
 __handle_mm_fault mm/memory.c:4785 [inline]
 handle_mm_fault+0x1b16/0x4410 mm/memory.c:4883
 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1355
 handle_page_fault arch/x86/mm/fault.c:1443 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0010:do_sys_poll+0xf56/0x11a0 fs/select.c:1025
Code: 8b 74 24 30 4c 8d 76 12 48 8b 54 24 68 48 83 c2 06 45 31 ff 4c 89 f0 48 c1 e8 03 42 0f b6 04 28 84 c0 75 2b 42 0f b7 44 fe 12 <66> 89 02 49 89 d4 44 39 fb 74 3b e8 9a df aa ff 49 ff c7 49 83 c6
RSP: 0000:ffffc90002e2f860 EFLAGS: 00050246
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff888027253b80
RDX: 000055d6489dd7e6 RSI: ffffc90002e2fc70 RDI: 0000000000000000
RBP: ffffc90002e2fe10 R08: ffff888078b8af7f R09: 1ffff1100f1715ef
R10: dffffc0000000000 R11: ffffed100f1715f0 R12: 000055d6489dd7f0
R13: dffffc0000000000 R14: ffffc90002e2fc82 R15: 0000000000000000
 __do_sys_ppoll fs/select.c:1120 [inline]
 __se_sys_ppoll+0x206/0x2a0 fs/select.c:1100
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9ad4ece407
Code: Unable to access opcode bytes at RIP 0x7f9ad4ece3dd.
RSP: 002b:00007fff087cc510 EFLAGS: 00000202 ORIG_RAX: 000000000000010f
RAX: ffffffffffffffda RBX: 00007f9ad4dda300 RCX: 00007f9ad4ece407
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 000055d6489dd7e0
RBP: 0000000000000002 R08: 0000000000000008 R09: 0000000000000000
R10: 00007fff087cc7e0 R11: 0000000000000202 R12: 0000000000000064
R13: 0000000000000000 R14: 000055d622ff1004 R15: 0000000000000002
 </TASK>
Kernel Offset: disabled
Rebooting in 86400 seconds..
----------------
Code disassembly (best guess):
   0:	8b 74 24 30          	mov    0x30(%rsp),%esi
   4:	4c 8d 76 12          	lea    0x12(%rsi),%r14
   8:	48 8b 54 24 68       	mov    0x68(%rsp),%rdx
   d:	48 83 c2 06          	add    $0x6,%rdx
  11:	45 31 ff             	xor    %r15d,%r15d
  14:	4c 89 f0             	mov    %r14,%rax
  17:	48 c1 e8 03          	shr    $0x3,%rax
  1b:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax
  20:	84 c0                	test   %al,%al
  22:	75 2b                	jne    0x4f
  24:	42 0f b7 44 fe 12    	movzwl 0x12(%rsi,%r15,8),%eax
* 2a:	66 89 02             	mov    %ax,(%rdx) <-- trapping instruction
  2d:	49 89 d4             	mov    %rdx,%r12
  30:	44 39 fb             	cmp    %r15d,%ebx
  33:	74 3b                	je     0x70
  35:	e8 9a df aa ff       	call   0xffaadfd4
  3a:	49 ff c7             	inc    %r15
  3d:	49                   	rex.WB
  3e:	83                   	.byte 0x83
  3f:	c6                   	.byte 0xc6

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/28 08:50 linux-5.15.y b9d57c40a767 ce741359 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf kernel panic: System is deadlocked on memory
* Struck through repros no longer work on HEAD.