general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 0 PID: 10723 Comm: syz.6.1514 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 RIP: 0010:__percpu_ref_switch_mode+0x123/0x5f0 lib/percpu-refcount.c:277 Code: 31 ff 89 c6 e8 6e 7a 59 fd 45 85 ff 0f 84 5a 04 00 00 e8 b0 76 59 fd eb 05 e8 a9 76 59 fd 4d 8d 74 24 10 4d 89 f5 49 c1 ed 03 <41> 80 7c 1d 00 00 74 08 4c 89 f7 e8 3d 7f b2 fd 49 83 3e 00 0f 84 RSP: 0018:ffffc90019bcf8e0 EFLAGS: 00010002 RAX: ffffffff842e67f0 RBX: dffffc0000000000 RCX: 0000000000080000 RDX: ffffc9000eb49000 RSI: 00000000000026e4 RDI: 00000000000026e5 RBP: ffffc90019bcf9f8 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52003379f1c R12: 0000000000000000 R13: 0000000000000002 R14: 0000000000000010 R15: 0000000000000001 FS: 00007f94a00da6c0(0000) GS:ffff8880b8c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f88edd556c8 CR3: 000000006007d000 CR4: 00000000003526f0 Call Trace: percpu_ref_kill_and_confirm+0x9b/0x130 lib/percpu-refcount.c:395 percpu_ref_kill include/linux/percpu-refcount.h:149 [inline] __mddev_suspend+0x2d1/0x630 drivers/md/md.c:533 mddev_suspend_and_lock drivers/md/md.h:876 [inline] raid_disks_store+0xb8/0x550 drivers/md/md.c:4320 md_attr_store+0x19c/0x390 drivers/md/md.c:5756 kernfs_fop_write_iter+0x3a4/0x520 fs/kernfs/file.c:352 call_write_iter include/linux/fs.h:2019 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x474/0x9a0 fs/read_write.c:584 ksys_write+0x151/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f949f19f559 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f94a00da028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f949f426090 RCX: 00007f949f19f559 RDX: 0000000000000001 RSI: 0000200000000180 RDI: 0000000000000006 RBP: 00007f949f236b50 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f949f426128 R14: 00007f949f426090 R15: 00007ffe48dc4b38 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__percpu_ref_switch_mode+0x123/0x5f0 lib/percpu-refcount.c:277 Code: 31 ff 89 c6 e8 6e 7a 59 fd 45 85 ff 0f 84 5a 04 00 00 e8 b0 76 59 fd eb 05 e8 a9 76 59 fd 4d 8d 74 24 10 4d 89 f5 49 c1 ed 03 <41> 80 7c 1d 00 00 74 08 4c 89 f7 e8 3d 7f b2 fd 49 83 3e 00 0f 84 RSP: 0018:ffffc90019bcf8e0 EFLAGS: 00010002 RAX: ffffffff842e67f0 RBX: dffffc0000000000 RCX: 0000000000080000 RDX: ffffc9000eb49000 RSI: 00000000000026e4 RDI: 00000000000026e5 RBP: ffffc90019bcf9f8 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52003379f1c R12: 0000000000000000 R13: 0000000000000002 R14: 0000000000000010 R15: 0000000000000001 FS: 00007f94a00da6c0(0000) GS:ffff8880b8c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f88edd556c8 CR3: 000000006007d000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: 31 ff xor %edi,%edi 2: 89 c6 mov %eax,%esi 4: e8 6e 7a 59 fd call 0xfd597a77 9: 45 85 ff test %r15d,%r15d c: 0f 84 5a 04 00 00 je 0x46c 12: e8 b0 76 59 fd call 0xfd5976c7 17: eb 05 jmp 0x1e 19: e8 a9 76 59 fd call 0xfd5976c7 1e: 4d 8d 74 24 10 lea 0x10(%r12),%r14 23: 4d 89 f5 mov %r14,%r13 26: 49 c1 ed 03 shr $0x3,%r13 * 2a: 41 80 7c 1d 00 00 cmpb $0x0,0x0(%r13,%rbx,1) <-- trapping instruction 30: 74 08 je 0x3a 32: 4c 89 f7 mov %r14,%rdi 35: e8 3d 7f b2 fd call 0xfdb27f77 3a: 49 83 3e 00 cmpq $0x0,(%r14) 3e: 0f .byte 0xf 3f: 84 .byte 0x84