BUG: sleeping function called from invalid context at kernel/workqueue.c:3414 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 8334, name: syz.1.517 preempt_count: 100, expected: 0 RCU nest depth: 0, expected: 0 3 locks held by syz.1.517/8334: #0: ffff88801aa52418 (sb_writers#5){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #1: ffff8880773d1730 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #1: ffff8880773d1730 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: shmem_file_write_iter+0x82/0x120 mm/shmem.c:2873 #2: ffffc900001f0be0 ((&vub300->inactivity_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd2/0x540 kernel/time/timer.c:1698 Preemption disabled at: [] softirq_handle_begin kernel/softirq.c:419 [inline] [] handle_softirqs+0x101/0x820 kernel/softirq.c:554 CPU: 1 PID: 8334 Comm: syz.1.517 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 __might_resched+0x48d/0x5f0 kernel/sched/core.c:10264 start_flush_work kernel/workqueue.c:3414 [inline] __flush_work+0x10f/0xac0 kernel/workqueue.c:3474 __cancel_work_timer+0x3f8/0x560 kernel/workqueue.c:3562 mmc_free_host+0x19/0x40 drivers/mmc/core/host.c:694 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x570/0x810 kernel/time/timer.c:2023 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036 handle_softirqs+0x27d/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__sanitizer_cov_trace_pc+0x3b/0x60 kernel/kcov.c:215 Code: 8b 15 11 e4 7b 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 24 16 00 00 00 74 2c 8b 91 00 16 00 00 83 fa 02 75 21 <48> 8b 91 08 16 00 00 48 8b 32 48 8d 7e 01 8b 89 04 16 00 00 48 39 RSP: 0018:ffffc900036e6fe0 EFLAGS: 00000246 RAX: ffffffff813c17e8 RBX: ffffc900036e7048 RCX: ffff88802b778000 RDX: 0000000000000002 RSI: ffffc900036e70d0 RDI: ffffc900036e7048 RBP: 1ffff920006dce09 R08: ffff88802b778000 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000002 R12: ffffc900036e7048 R13: ffffc900036e7050 R14: dffffc0000000000 R15: ffffc900036e70d0 __unwind_start+0x598/0x730 arch/x86/kernel/unwind_orc.c:757 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xf8/0x190 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 save_stack+0x125/0x230 mm/page_owner.c:128 __set_page_owner+0x1d/0x60 mm/page_owner.c:192 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582 prep_new_page mm/page_alloc.c:1589 [inline] get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501 __folio_alloc+0x10/0x20 mm/page_alloc.c:4533 vma_alloc_folio+0x474/0x8f0 mm/mempolicy.c:2240 shmem_alloc_folio+0x1a9/0x2a0 mm/shmem.c:1679 shmem_alloc_and_acct_folio+0x1cb/0x6c0 mm/shmem.c:1704 shmem_get_folio_gfp+0xe1d/0x2b40 mm/shmem.c:2041 shmem_get_folio mm/shmem.c:2164 [inline] shmem_write_begin+0xf2/0x430 mm/shmem.c:2706 generic_perform_write+0x2fe/0x5c0 mm/filemap.c:4027 shmem_file_write_iter+0xfb/0x120 mm/shmem.c:2883 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: 0033:0x7f2b61d5fd8e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007f2b5fff5da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f2b5fff66c0 RCX: 00007f2b61d5fd8e RDX: 00000000013bd7ef RSI: 00007f2b57bd6000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007f2b5fff5ee0 R14: 00007f2b5fff5ea0 R15: 00007f2b57bd6000 vkms_vblank_simulate: vblank timer overrun ODEBUG: object ffffc900001f09c0 is NOT on stack ffffc900036e0000, but annotated. ====================================================== ---------------- Code disassembly (best guess): 0: 8b 15 11 e4 7b 7e mov 0x7e7be411(%rip),%edx # 0x7e7be417 6: 81 e2 00 01 ff 00 and $0xff0100,%edx c: 74 11 je 0x1f e: 81 fa 00 01 00 00 cmp $0x100,%edx 14: 75 35 jne 0x4b 16: 83 b9 24 16 00 00 00 cmpl $0x0,0x1624(%rcx) 1d: 74 2c je 0x4b 1f: 8b 91 00 16 00 00 mov 0x1600(%rcx),%edx 25: 83 fa 02 cmp $0x2,%edx 28: 75 21 jne 0x4b * 2a: 48 8b 91 08 16 00 00 mov 0x1608(%rcx),%rdx <-- trapping instruction 31: 48 8b 32 mov (%rdx),%rsi 34: 48 8d 7e 01 lea 0x1(%rsi),%rdi 38: 8b 89 04 16 00 00 mov 0x1604(%rcx),%ecx 3e: 48 rex.W 3f: 39 .byte 0x39