RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ============================================ WARNING: possible recursive locking detected syzkaller #0 Tainted: G L -------------------------------------------- syz.1.3032/17818 is trying to acquire lock: ffffffff8e901928 (fw_lock){+.+.}-{4:4}, at: assign_fw+0x52/0x8e0 drivers/base/firmware_loader/main.c:700 but task is already holding lock: ffffffff8e901928 (fw_lock){+.+.}-{4:4}, at: device_cache_fw_images drivers/base/firmware_loader/main.c:1504 [inline] ffffffff8e901928 (fw_lock){+.+.}-{4:4}, at: fw_pm_notify+0x1e8/0x2d0 drivers/base/firmware_loader/main.c:1557 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(fw_lock); lock(fw_lock); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz.1.3032/17818: #0: ffffffff8e79fce8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 #1: ffffffff8ddf09a8 (system_transition_mutex){+.+.}-{4:4}, at: lock_system_sleep+0x4a/0x70 kernel/power/main.c:71 #2: ffffffff8de14770 ((pm_chain_head).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain_robust+0x65/0x100 kernel/notifier.c:344 #3: ffffffff8e901928 (fw_lock){+.+.}-{4:4}, at: device_cache_fw_images drivers/base/firmware_loader/main.c:1504 [inline] #3: ffffffff8e901928 (fw_lock){+.+.}-{4:4}, at: fw_pm_notify+0x1e8/0x2d0 drivers/base/firmware_loader/main.c:1557 #4: ffffffff8e8fc888 (dpm_list_mtx){+.+.}-{4:4}, at: device_pm_lock drivers/base/power/main.c:127 [inline] #4: ffffffff8e8fc888 (dpm_list_mtx){+.+.}-{4:4}, at: dpm_for_each_dev+0x29/0xb0 drivers/base/power/main.c:2323 stack backtrace: CPU: 0 UID: 0 PID: 17818 Comm: syz.1.3032 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_deadlock_bug+0x279/0x290 kernel/locking/lockdep.c:3041 check_deadlock kernel/locking/lockdep.c:3093 [inline] validate_chain kernel/locking/lockdep.c:3895 [inline] __lock_acquire+0x2540/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776 assign_fw+0x52/0x8e0 drivers/base/firmware_loader/main.c:700 _request_firmware+0xf08/0x1680 drivers/base/firmware_loader/main.c:901 request_firmware drivers/base/firmware_loader/main.c:948 [inline] cache_firmware drivers/base/firmware_loader/main.c:1286 [inline] __async_dev_cache_fw_image+0x7f/0x2d0 drivers/base/firmware_loader/main.c:1400 async_schedule_node_domain+0xe1/0x120 kernel/async.c:221 async_schedule_domain include/linux/async.h:72 [inline] dev_cache_fw_image+0x364/0x3e0 drivers/base/firmware_loader/main.c:1456 dpm_for_each_dev+0x56/0xb0 drivers/base/power/main.c:2325 device_cache_fw_images drivers/base/firmware_loader/main.c:1506 [inline] fw_pm_notify+0x200/0x2d0 drivers/base/firmware_loader/main.c:1557 notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85 notifier_call_chain_robust kernel/notifier.c:120 [inline] blocking_notifier_call_chain_robust+0x85/0x100 kernel/notifier.c:345 pm_notifier_call_chain_robust+0x2c/0x60 kernel/power/main.c:172 snapshot_open+0x133/0x280 kernel/power/user.c:87 misc_open+0x2d5/0x350 drivers/char/misc.c:163 chrdev_open+0x4cc/0x5e0 fs/char_dev.c:414 do_dentry_open+0x7ce/0x1420 fs/open.c:962 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:4628 [inline] path_openat+0x340e/0x3dd0 fs/namei.c:4787 do_filp_open+0x1fa/0x410 fs/namei.c:4814 do_sys_openat2+0x121/0x200 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_compat_sys_openat fs/open.c:1498 [inline] __se_compat_sys_openat fs/open.c:1496 [inline] __ia32_compat_sys_openat+0x131/0x160 fs/open.c:1496 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x1dc/0x570 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf700d539 Code: 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 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f53fd55c EFLAGS: 00000206 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 00000000800002c0 RDX: 0000000000042801 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 4: 10 07 adc %al,(%rdi) 6: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi a: 10 08 adc %cl,(%rax) c: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 20: 00 51 52 add %dl,0x52(%rcx) 23: 55 push %rbp 24: 89 e5 mov %esp,%ebp 26: 0f 34 sysenter 28: cd 80 int $0x80 * 2a: 5d pop %rbp <-- trapping instruction 2b: 5a pop %rdx 2c: 59 pop %rcx 2d: c3 ret 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop