Oops: general protection fault, probably for non-canonical address 0xdffffc0000000030: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000180-0x0000000000000187]
CPU: 1 PID: 13172 Comm: syz-executor.0 Not tainted 6.9.0-syzkaller-08995-g0450d2083be6 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:rcu_seq_done kernel/rcu/rcu.h:156 [inline]
RIP: 0010:poll_state_synchronize_srcu+0x43/0x90 kernel/rcu/srcutree.c:1543
Code: 48 83 ec 08 48 c1 ea 03 80 3c 02 00 75 45 48 b8 00 00 00 00 00 fc ff df 48 8b 5b 38 48 8d bb 80 01 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 32 48 8b 93 80 01 00 00 31 c0 48 39 f2 78 0b f0 83
RSP: 0018:ffffc900036cf4e0 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90027ec9000
RDX: 0000000000000030 RSI: 0000000000000004 RDI: 0000000000000180
RBP: dffffc0000000000 R08: 0000000000000000 R09: fffffbfff283de73
R10: ffffffff941ef39f R11: 00000000000001db R12: ffff8880551e4790
R13: ffff8880551e4810 R14: ffff888059780000 R15: ffff888059780000
FS:  0000000000000000(0000) GS:ffff88802c100000(0063) knlGS:00000000f5e98b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f740d0c4 CR3: 0000000028fde000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 bch2_btree_key_cache_scan+0x376/0x1740 fs/bcachefs/btree_key_cache.c:846
 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435
 shrink_slab+0x18a/0x1310 mm/shrinker.c:662
 drop_slab_node mm/vmscan.c:393 [inline]
 drop_slab+0x14c/0x2c0 mm/vmscan.c:411
 drop_caches_sysctl_handler+0x171/0x190 fs/drop_caches.c:68
 proc_sys_call_handler+0x4cc/0x6f0 fs/proc/proc_sysctl.c:592
 call_write_iter include/linux/fs.h:2120 [inline]
 iter_file_splice_write+0x906/0x10b0 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x19b/0x6d0 fs/splice.c:1164
 splice_direct_to_actor+0x346/0xa40 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0x17e/0x250 fs/splice.c:1233
 do_sendfile+0xaa8/0xdb0 fs/read_write.c:1295
 __do_compat_sys_sendfile fs/read_write.c:1377 [inline]
 __se_compat_sys_sendfile fs/read_write.c:1366 [inline]
 __ia32_compat_sys_sendfile+0x163/0x230 fs/read_write.c:1366
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf72c7579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f5e985ac EFLAGS: 00000292 ORIG_RAX: 00000000000000bb
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000000003
RDX: 0000000020002080 RSI: 000000000000023b RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:rcu_seq_done kernel/rcu/rcu.h:156 [inline]
RIP: 0010:poll_state_synchronize_srcu+0x43/0x90 kernel/rcu/srcutree.c:1543
Code: 48 83 ec 08 48 c1 ea 03 80 3c 02 00 75 45 48 b8 00 00 00 00 00 fc ff df 48 8b 5b 38 48 8d bb 80 01 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 32 48 8b 93 80 01 00 00 31 c0 48 39 f2 78 0b f0 83
RSP: 0018:ffffc900036cf4e0 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90027ec9000
RDX: 0000000000000030 RSI: 0000000000000004 RDI: 0000000000000180
RBP: dffffc0000000000 R08: 0000000000000000 R09: fffffbfff283de73
R10: ffffffff941ef39f R11: 00000000000001db R12: ffff8880551e4790
R13: ffff8880551e4810 R14: ffff888059780000 R15: ffff888059780000
FS:  0000000000000000(0000) GS:ffff88802c000000(0063) knlGS:00000000f5e98b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000002062e000 CR3: 0000000028fde000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	48 83 ec 08          	sub    $0x8,%rsp
   4:	48 c1 ea 03          	shr    $0x3,%rdx
   8:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   c:	75 45                	jne    0x53
   e:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  15:	fc ff df
  18:	48 8b 5b 38          	mov    0x38(%rbx),%rbx
  1c:	48 8d bb 80 01 00 00 	lea    0x180(%rbx),%rdi
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	75 32                	jne    0x62
  30:	48 8b 93 80 01 00 00 	mov    0x180(%rbx),%rdx
  37:	31 c0                	xor    %eax,%eax
  39:	48 39 f2             	cmp    %rsi,%rdx
  3c:	78 0b                	js     0x49
  3e:	f0                   	lock
  3f:	83                   	.byte 0x83