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* [syzbot] [kernfs?] possible deadlock in lookup_slow (3)
@ 2023-07-19 13:17 syzbot
  2026-03-13  3:08 ` syzbot
  0 siblings, 1 reply; 2+ messages in thread
From: syzbot @ 2023-07-19 13:17 UTC (permalink / raw)
  To: gregkh, linux-fsdevel, linux-kernel, syzkaller-bugs, tj

Hello,

syzbot found the following issue on:

HEAD commit:    ccff6d117d8d Merge tag 'perf-tools-fixes-for-v6.5-1-2023-0..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13b20fa2a80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a4507c291b5ab5d4
dashboard link: https://syzkaller.appspot.com/bug?extid=65459fd3b61877d717a3
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9e214fc8e043/disk-ccff6d11.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0791f1cf1876/vmlinux-ccff6d11.xz
kernel image: https://storage.googleapis.com/syzbot-assets/92b6acf6a807/bzImage-ccff6d11.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+65459fd3b61877d717a3@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
6.5.0-rc2-syzkaller-00046-gccff6d117d8d #0 Not tainted
------------------------------------------------------
syz-executor.4/14533 is trying to acquire lock:
ffff888054161e80 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:781 [inline]
ffff888054161e80 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1706

but task is already holding lock:
ffff88804425e488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x4f0 fs/kernfs/file.c:325

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&of->mutex){+.+.}-{3:3}:
       __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
       kernfs_seq_start+0x53/0x3a0 fs/kernfs/file.c:154
       seq_read_iter+0x3d4/0xd10 fs/seq_file.c:225
       call_read_iter include/linux/fs.h:1865 [inline]
       new_sync_read fs/read_write.c:389 [inline]
       vfs_read+0x795/0xb00 fs/read_write.c:470
       ksys_read+0x1a0/0x2c0 fs/read_write.c:613
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #2 (&p->lock){+.+.}-{3:3}:
       __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
       seq_read_iter+0xb2/0xd10 fs/seq_file.c:182
       call_read_iter include/linux/fs.h:1865 [inline]
       copy_splice_read+0x4c9/0x9c0 fs/splice.c:367
       splice_direct_to_actor+0x2c4/0x9e0 fs/splice.c:1070
       do_splice_direct+0x2ac/0x3f0 fs/splice.c:1195
       do_sendfile+0x623/0x1070 fs/read_write.c:1254
       __do_sys_sendfile64 fs/read_write.c:1322 [inline]
       __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1308
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #1 (sb_writers#4){.+.+}-{0:0}:
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1494 [inline]
       sb_start_write+0x4d/0x1c0 include/linux/fs.h:1569
       mnt_want_write+0x3f/0x90 fs/namespace.c:403
       ovl_create_object+0xf8/0x300 fs/overlayfs/dir.c:629
       lookup_open fs/namei.c:3492 [inline]
       open_last_lookups fs/namei.c:3560 [inline]
       path_openat+0x13e7/0x3180 fs/namei.c:3790
       do_filp_open+0x234/0x490 fs/namei.c:3820
       do_sys_openat2+0x13e/0x1d0 fs/open.c:1407
       do_sys_open fs/open.c:1422 [inline]
       __do_sys_openat fs/open.c:1438 [inline]
       __se_sys_openat fs/open.c:1433 [inline]
       __x64_sys_openat+0x247/0x290 fs/open.c:1433
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3142 [inline]
       check_prevs_add kernel/locking/lockdep.c:3261 [inline]
       validate_chain kernel/locking/lockdep.c:3876 [inline]
       __lock_acquire+0x39ff/0x7f70 kernel/locking/lockdep.c:5144
       lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5761
       down_read+0x47/0x2f0 kernel/locking/rwsem.c:1520
       inode_lock_shared include/linux/fs.h:781 [inline]
       lookup_slow+0x45/0x70 fs/namei.c:1706
       walk_component+0x2d0/0x400 fs/namei.c:1998
       lookup_last fs/namei.c:2455 [inline]
       path_lookupat+0x16f/0x450 fs/namei.c:2479
       filename_lookup+0x255/0x610 fs/namei.c:2508
       kern_path+0x3b/0x180 fs/namei.c:2606
       lookup_bdev+0xc5/0x290 block/bdev.c:943
       resume_store+0x19c/0x700 kernel/power/hibernate.c:1177
       kernfs_fop_write_iter+0x3a6/0x4f0 fs/kernfs/file.c:334
       call_write_iter include/linux/fs.h:1871 [inline]
       new_sync_write fs/read_write.c:491 [inline]
       vfs_write+0x782/0xaf0 fs/read_write.c:584
       ksys_write+0x1a0/0x2c0 fs/read_write.c:637
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

Chain exists of:
  &ovl_i_mutex_dir_key[depth] --> &p->lock --> &of->mutex

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&of->mutex);
                               lock(&p->lock);
                               lock(&of->mutex);
  rlock(&ovl_i_mutex_dir_key[depth]);

 *** DEADLOCK ***

4 locks held by syz-executor.4/14533:
 #0: ffff88807cfc45c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x254/0x2f0 fs/file.c:1047
 #1: ffff88802d7ec410 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x216/0xaf0 fs/read_write.c:580
 #2: ffff88804425e488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x4f0 fs/kernfs/file.c:325
 #3: ffff888019277e88 (kn->active#62){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x4f0 fs/kernfs/file.c:326

stack backtrace:
CPU: 0 PID: 14533 Comm: syz-executor.4 Not tainted 6.5.0-rc2-syzkaller-00046-gccff6d117d8d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x375/0x4a0 kernel/locking/lockdep.c:2195
 check_prev_add kernel/locking/lockdep.c:3142 [inline]
 check_prevs_add kernel/locking/lockdep.c:3261 [inline]
 validate_chain kernel/locking/lockdep.c:3876 [inline]
 __lock_acquire+0x39ff/0x7f70 kernel/locking/lockdep.c:5144
 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5761
 down_read+0x47/0x2f0 kernel/locking/rwsem.c:1520
 inode_lock_shared include/linux/fs.h:781 [inline]
 lookup_slow+0x45/0x70 fs/namei.c:1706
 walk_component+0x2d0/0x400 fs/namei.c:1998
 lookup_last fs/namei.c:2455 [inline]
 path_lookupat+0x16f/0x450 fs/namei.c:2479
 filename_lookup+0x255/0x610 fs/namei.c:2508
 kern_path+0x3b/0x180 fs/namei.c:2606
 lookup_bdev+0xc5/0x290 block/bdev.c:943
 resume_store+0x19c/0x700 kernel/power/hibernate.c:1177
 kernfs_fop_write_iter+0x3a6/0x4f0 fs/kernfs/file.c:334
 call_write_iter include/linux/fs.h:1871 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x782/0xaf0 fs/read_write.c:584
 ksys_write+0x1a0/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f538d87cb29
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f538e5020c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f538d99bf80 RCX: 00007f538d87cb29
RDX: 0000000000000012 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 00007f538d8c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f538d99bf80 R15: 00007ffc07e8a938
 </TASK>
PM: Image not found (code -6)


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the bug is already fixed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to change bug's subsystems, reply with:
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(See the list of subsystem names on the web dashboard)

If the bug is a duplicate of another bug, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [syzbot] [kernfs?] possible deadlock in lookup_slow (3)
  2023-07-19 13:17 [syzbot] [kernfs?] possible deadlock in lookup_slow (3) syzbot
@ 2026-03-13  3:08 ` syzbot
  0 siblings, 0 replies; 2+ messages in thread
From: syzbot @ 2026-03-13  3:08 UTC (permalink / raw)
  To: driver-core, gregkh, linux-fsdevel, linux-kernel, syzkaller-bugs,
	tj

syzbot has found a reproducer for the following issue on:

HEAD commit:    8004279c41ad Merge tag 'nfs-for-7.0-2' of git://git.linux-..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12f9775a580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=294595c42a927f55
dashboard link: https://syzkaller.appspot.com/bug?extid=65459fd3b61877d717a3
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1429cd52580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=162eff5a580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8d1ce7fc684d/disk-8004279c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9d97f0127a44/vmlinux-8004279c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f36219283bb9/bzImage-8004279c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+65459fd3b61877d717a3@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.17/6008 is trying to acquire lock:
ffff88807982dab8 (&type->i_mutex_dir_key#6){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline]
ffff88807982dab8 (&type->i_mutex_dir_key#6){++++}-{4:4}, at: lookup_slow+0x42/0x70 fs/namei.c:1932

but task is already holding lock:
ffffffff8e69df08 (param_lock){+.+.}-{4:4}, at: kernel_param_lock kernel/params.c:602 [inline]
ffffffff8e69df08 (param_lock){+.+.}-{4:4}, at: param_attr_store+0xec/0x300 kernel/params.c:587

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (param_lock){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:614 [inline]
       __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776
       ieee80211_rate_control_ops_get net/mac80211/rate.c:223 [inline]
       rate_control_alloc net/mac80211/rate.c:269 [inline]
       ieee80211_init_rate_ctrl_alg+0x1df/0x3b0 net/mac80211/rate.c:1016
       ieee80211_register_hw+0x2950/0x4140 net/mac80211/main.c:1544
       mac80211_hwsim_new_radio+0x2847/0x57d0 drivers/net/wireless/virtual/mac80211_hwsim.c:5810
       init_mac80211_hwsim+0x6db/0x7f0 drivers/net/wireless/virtual/mac80211_hwsim.c:7173
       do_one_initcall+0x11d/0x760 init/main.c:1382
       do_initcall_level init/main.c:1444 [inline]
       do_initcalls init/main.c:1460 [inline]
       do_basic_setup init/main.c:1479 [inline]
       kernel_init_freeable+0x6e5/0x7a0 init/main.c:1692
       kernel_init+0x1f/0x1e0 init/main.c:1582
       ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

-> #2 (rtnl_mutex){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:614 [inline]
       __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776
       cgrp_css_online+0xa1/0x1f0 net/core/netprio_cgroup.c:157
       online_css+0xb2/0x350 kernel/cgroup/cgroup.c:5732
       css_create kernel/cgroup/cgroup.c:5820 [inline]
       cgroup_apply_control_enable+0x8bd/0xbd0 kernel/cgroup/cgroup.c:3389
       cgroup_mkdir+0x57f/0x1330 kernel/cgroup/cgroup.c:6021
       kernfs_iop_mkdir+0x111/0x190 fs/kernfs/dir.c:1273
       vfs_mkdir+0x361/0x850 fs/namei.c:5233
       filename_mkdirat+0x48b/0x5e0 fs/namei.c:5266
       __do_sys_mkdirat fs/namei.c:5287 [inline]
       __se_sys_mkdirat fs/namei.c:5284 [inline]
       __x64_sys_mkdirat+0x89/0xc0 fs/namei.c:5284
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (cgroup_mutex){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:614 [inline]
       __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776
       cgroup_lock include/linux/cgroup.h:394 [inline]
       cgroup_kn_lock_live+0x116/0x520 kernel/cgroup/cgroup.c:1732
       cgroup_rmdir+0x22/0x2e0 kernel/cgroup/cgroup.c:6226
       kernfs_iop_rmdir+0x106/0x170 fs/kernfs/dir.c:1291
       vfs_rmdir fs/namei.c:5338 [inline]
       vfs_rmdir+0x328/0x8a0 fs/namei.c:5311
       filename_rmdir+0x31a/0x5c0 fs/namei.c:5393
       __do_sys_rmdir fs/namei.c:5416 [inline]
       __se_sys_rmdir fs/namei.c:5413 [inline]
       __x64_sys_rmdir+0x46/0x70 fs/namei.c:5413
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&type->i_mutex_dir_key#6){++++}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3165 [inline]
       check_prevs_add kernel/locking/lockdep.c:3284 [inline]
       validate_chain kernel/locking/lockdep.c:3908 [inline]
       __lock_acquire+0x14b8/0x2630 kernel/locking/lockdep.c:5237
       lock_acquire kernel/locking/lockdep.c:5868 [inline]
       lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825
       down_read+0x99/0x460 kernel/locking/rwsem.c:1537
       inode_lock_shared include/linux/fs.h:1043 [inline]
       lookup_slow+0x42/0x70 fs/namei.c:1932
       walk_component fs/namei.c:2279 [inline]
       lookup_last fs/namei.c:2780 [inline]
       path_lookupat+0x5e8/0xc40 fs/namei.c:2804
       filename_lookup+0x202/0x590 fs/namei.c:2833
       kern_path+0x37/0x50 fs/namei.c:3040
       lookup_bdev+0xd8/0x280 block/bdev.c:1221
       bdev_file_open_by_path+0x82/0x330 block/bdev.c:1094
       add_device drivers/mtd/devices/block2mtd.c:279 [inline]
       block2mtd_setup2.isra.0+0x2ee/0xc70 drivers/mtd/devices/block2mtd.c:459
       block2mtd_setup+0xbd/0xd0 drivers/mtd/devices/block2mtd.c:476
       param_attr_store+0x199/0x300 kernel/params.c:589
       module_attr_store+0x58/0x80 kernel/params.c:913
       sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:142
       kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:352
       new_sync_write fs/read_write.c:595 [inline]
       vfs_write+0x6ac/0x1070 fs/read_write.c:688
       ksys_write+0x12a/0x250 fs/read_write.c:740
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &type->i_mutex_dir_key#6 --> rtnl_mutex --> param_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(param_lock);
                               lock(rtnl_mutex);
                               lock(param_lock);
  rlock(&type->i_mutex_dir_key#6);

 *** DEADLOCK ***

4 locks held by syz.0.17/6008:
 #0: ffff888037100420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:740
 #1: ffff888063a41488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343
 #2: ffff88803515ee18 (kn->active#4){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff88803515ee18 (kn->active#4){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344
 #3: ffffffff8e69df08 (param_lock){+.+.}-{4:4}, at: kernel_param_lock kernel/params.c:602 [inline]
 #3: ffffffff8e69df08 (param_lock){+.+.}-{4:4}, at: param_attr_store+0xec/0x300 kernel/params.c:587

stack backtrace:
CPU: 1 UID: 0 PID: 6008 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_circular_bug.cold+0x178/0x1c7 kernel/locking/lockdep.c:2043
 check_noncircular+0x146/0x160 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3165 [inline]
 check_prevs_add kernel/locking/lockdep.c:3284 [inline]
 validate_chain kernel/locking/lockdep.c:3908 [inline]
 __lock_acquire+0x14b8/0x2630 kernel/locking/lockdep.c:5237
 lock_acquire kernel/locking/lockdep.c:5868 [inline]
 lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825
 down_read+0x99/0x460 kernel/locking/rwsem.c:1537
 inode_lock_shared include/linux/fs.h:1043 [inline]
 lookup_slow+0x42/0x70 fs/namei.c:1932
 walk_component fs/namei.c:2279 [inline]
 lookup_last fs/namei.c:2780 [inline]
 path_lookupat+0x5e8/0xc40 fs/namei.c:2804
 filename_lookup+0x202/0x590 fs/namei.c:2833
 kern_path+0x37/0x50 fs/namei.c:3040
 lookup_bdev+0xd8/0x280 block/bdev.c:1221
 bdev_file_open_by_path+0x82/0x330 block/bdev.c:1094
 add_device drivers/mtd/devices/block2mtd.c:279 [inline]
 block2mtd_setup2.isra.0+0x2ee/0xc70 drivers/mtd/devices/block2mtd.c:459
 block2mtd_setup+0xbd/0xd0 drivers/mtd/devices/block2mtd.c:476
 param_attr_store+0x199/0x300 kernel/params.c:589
 module_attr_store+0x58/0x80 kernel/params.c:913
 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:142
 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:352
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6ac/0x1070 fs/read_write.c:688
 ksys_write+0x12a/0x250 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faeae79c799
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:00007ffd3b6d7408 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007faeaea15fa0 RCX: 00007faeae79c799
RDX: 0000000000000025 RSI: 0000200000000000 RDI: 0000000000000004
RBP: 00007faeae832c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007faeaea15fac R14: 00007faeaea15fa0 R15: 00007faeaea15fa0
 </TASK>
block2mtd: error: cannot open device �inX�����\x14±��jFB�\x1eB>U�;߸\x0f�Ilk�


---
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