RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ============================================ WARNING: possible recursive locking detected 6.15.0-rc3-syzkaller-00019-gbc3372351d0c #0 Not tainted -------------------------------------------- syz.2.3491/17979 is trying to acquire lock: ffffffff8f701648 (fw_lock){+.+.}-{4:4}, at: assign_fw+0x56/0x890 drivers/base/firmware_loader/main.c:700 but task is already holding lock: ffffffff8f701648 (fw_lock){+.+.}-{4:4}, at: device_cache_fw_images drivers/base/firmware_loader/main.c:1548 [inline] ffffffff8f701648 (fw_lock){+.+.}-{4:4}, at: fw_pm_notify+0x23c/0x2f0 drivers/base/firmware_loader/main.c:1601 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.2.3491/17979: #0: ffffffff8f5afa68 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x54/0x340 drivers/char/misc.c:143 #1: ffffffff8ebee028 (system_transition_mutex){+.+.}-{4:4}, at: lock_system_sleep+0x60/0xa0 kernel/power/main.c:56 #2: ffffffff8ec11690 ((pm_chain_head).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain_robust+0xb8/0x1f0 kernel/notifier.c:344 #3: ffffffff8f701648 (fw_lock){+.+.}-{4:4}, at: device_cache_fw_images drivers/base/firmware_loader/main.c:1548 [inline] #3: ffffffff8f701648 (fw_lock){+.+.}-{4:4}, at: fw_pm_notify+0x23c/0x2f0 drivers/base/firmware_loader/main.c:1601 #4: ffffffff8f6fc8c8 (dpm_list_mtx){+.+.}-{4:4}, at: device_pm_lock drivers/base/power/main.c:113 [inline] #4: ffffffff8f6fc8c8 (dpm_list_mtx){+.+.}-{4:4}, at: dpm_for_each_dev+0x2b/0xc0 drivers/base/power/main.c:2059 stack backtrace: CPU: 1 UID: 0 PID: 17979 Comm: syz.2.3491 Not tainted 6.15.0-rc3-syzkaller-00019-gbc3372351d0c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_deadlock_bug+0x2be/0x2d0 kernel/locking/lockdep.c:3042 check_deadlock kernel/locking/lockdep.c:3094 [inline] validate_chain+0x928/0x24e0 kernel/locking/lockdep.c:3896 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x1a5/0x10c0 kernel/locking/mutex.c:746 assign_fw+0x56/0x890 drivers/base/firmware_loader/main.c:700 _request_firmware+0xfd1/0x1540 drivers/base/firmware_loader/main.c:944 request_firmware drivers/base/firmware_loader/main.c:992 [inline] cache_firmware drivers/base/firmware_loader/main.c:1330 [inline] __async_dev_cache_fw_image+0xf3/0x350 drivers/base/firmware_loader/main.c:1444 async_schedule_node_domain+0xdc/0x110 kernel/async.c:221 async_schedule_domain include/linux/async.h:72 [inline] dev_cache_fw_image+0x36f/0x3e0 drivers/base/firmware_loader/main.c:1500 dpm_for_each_dev+0x58/0xc0 drivers/base/power/main.c:2061 device_cache_fw_images drivers/base/firmware_loader/main.c:1550 [inline] fw_pm_notify+0x254/0x2f0 drivers/base/firmware_loader/main.c:1601 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 notifier_call_chain_robust kernel/notifier.c:120 [inline] blocking_notifier_call_chain_robust+0xf2/0x1f0 kernel/notifier.c:345 pm_notifier_call_chain_robust+0x2c/0x60 kernel/power/main.c:102 snapshot_open+0x132/0x280 kernel/power/user.c:87 misc_open+0x2cc/0x340 drivers/char/misc.c:179 chrdev_open+0x514/0x600 fs/char_dev.c:414 do_dentry_open+0xdec/0x1960 fs/open.c:956 vfs_open+0x3b/0x370 fs/open.c:1086 do_open fs/namei.c:3880 [inline] path_openat+0x2caf/0x35d0 fs/namei.c:4039 do_filp_open+0x284/0x4e0 fs/namei.c:4066 do_sys_openat2+0x12b/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_compat_sys_openat fs/open.c:1506 [inline] __se_compat_sys_openat fs/open.c:1504 [inline] __ia32_compat_sys_openat+0x241/0x290 fs/open.c:1504 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7f57539 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:00000000f507655c EFLAGS: 00000206 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 00000000800002c0 RDX: 0000000000040081 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