program: syz_usb_control_io(0xffffffffffffffff, 0x0, 0x0) r0 = openat$pmem0(0xffffffffffffff9c, &(0x7f0000002340), 0x80d01, 0x0) r1 = openat$pmem0(0xffffffffffffff9c, &(0x7f0000002340), 0x80d01, 0x0) ioctl$BLKPG(r1, 0x1269, &(0x7f00000001c0)={0x1, 0x0, 0x98, &(0x7f00000000c0)={0x0, 0x1000, 0xd}}) ioctl$BLKPG(r0, 0x1269, &(0x7f00000001c0)={0x2, 0x0, 0x98, &(0x7f00000000c0)={0x400, 0x1000, 0xd}}) [ 74.723304][ T5310] Bluetooth: hci0: command tx timeout [ 74.874450][ T5327] [ 74.875439][ T5327] ====================================================== [ 74.878173][ T5327] WARNING: possible circular locking dependency detected [ 74.880935][ T5327] 6.15.0-rc3-syzkaller-00032-ga79be02bba5c #0 Not tainted [ 74.883677][ T5327] ------------------------------------------------------ [ 74.886549][ T5327] syz.0.0/5327 is trying to acquire lock: [ 74.888783][ T5327] ffff88804009e2d8 (kn->active#5){++++}-{0:0}, at: __kernfs_remove+0x336/0x570 [ 74.892396][ T5327] [ 74.892396][ T5327] but task is already holding lock: [ 74.895383][ T5327] ffff88801f1b0358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_del_partition+0x25/0xe0 [ 74.899287][ T5327] [ 74.899287][ T5327] which lock already depends on the new lock. [ 74.899287][ T5327] [ 74.903432][ T5327] [ 74.903432][ T5327] the existing dependency chain (in reverse order) is: [ 74.907041][ T5327] [ 74.907041][ T5327] -> #2 (&disk->open_mutex){+.+.}-{4:4}: [ 74.910127][ T5327] lock_acquire+0x116/0x2f0 [ 74.912289][ T5327] __mutex_lock+0x1a5/0x10c0 [ 74.914844][ T5327] bdev_open+0xf7/0xcd0 [ 74.916716][ T5327] bdev_file_open_by_dev+0x1b2/0x230 [ 74.919019][ T5327] disk_scan_partitions+0x1be/0x2b0 [ 74.921324][ T5327] add_disk_fwnode+0xd26/0x1020 [ 74.923457][ T5327] pmem_attach_disk+0xd42/0x1020 [ 74.925720][ T5327] nvdimm_bus_probe+0x147/0x4e0 [ 74.927798][ T5327] really_probe+0x2b9/0xad0 [ 74.929798][ T5327] __driver_probe_device+0x1a2/0x390 [ 74.932170][ T5327] driver_probe_device+0x50/0x430 [ 74.934488][ T5327] __driver_attach+0x45f/0x710 [ 74.936508][ T5327] bus_for_each_dev+0x23e/0x2b0 [ 74.938531][ T5327] bus_add_driver+0x346/0x670 [ 74.940615][ T5327] driver_register+0x23a/0x320 [ 74.942663][ T5327] do_one_initcall+0x24a/0x940 [ 74.944966][ T5327] do_initcall_level+0x157/0x210 [ 74.947228][ T5327] do_initcalls+0x71/0xd0 [ 74.949100][ T5327] kernel_init_freeable+0x432/0x5d0 [ 74.951449][ T5327] kernel_init+0x1d/0x2b0 [ 74.953402][ T5327] ret_from_fork+0x4b/0x80 [ 74.955322][ T5327] ret_from_fork_asm+0x1a/0x30 [ 74.957497][ T5327] [ 74.957497][ T5327] -> #1 (&nvdimm_namespace_key){+.+.}-{4:4}: [ 74.960647][ T5327] lock_acquire+0x116/0x2f0 [ 74.962531][ T5327] __mutex_lock+0x1a5/0x10c0 [ 74.964442][ T5327] uevent_show+0x17d/0x340 [ 74.966284][ T5327] dev_attr_show+0x55/0xc0 [ 74.968088][ T5327] sysfs_kf_seq_show+0x32b/0x4a0 [ 74.970050][ T5327] seq_read_iter+0x461/0xda0 [ 74.971907][ T5327] vfs_read+0x9a0/0xb90 [ 74.973786][ T5327] ksys_read+0x19d/0x2d0 [ 74.975471][ T5327] do_syscall_64+0xf3/0x210 [ 74.977290][ T5327] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 74.979734][ T5327] [ 74.979734][ T5327] -> #0 (kn->active#5){++++}-{0:0}: [ 74.982599][ T5327] validate_chain+0xa69/0x24e0 [ 74.984653][ T5327] __lock_acquire+0xad5/0xd80 [ 74.986808][ T5327] lock_acquire+0x116/0x2f0 [ 74.988754][ T5327] kernfs_drain+0x275/0x5e0 [ 74.990742][ T5327] __kernfs_remove+0x336/0x570 [ 74.992826][ T5327] kernfs_remove_by_name_ns+0xad/0x130 [ 74.995367][ T5327] device_del+0x56c/0x9b0 [ 74.997317][ T5327] drop_partition+0x11b/0x180 [ 74.999437][ T5327] bdev_del_partition+0xb0/0xe0 [ 75.001516][ T5327] blkpg_do_ioctl+0x1fe/0x490 [ 75.003637][ T5327] blkdev_ioctl+0x6ba/0x710 [ 75.005756][ T5327] __se_sys_ioctl+0xf1/0x160 [ 75.007792][ T5327] do_syscall_64+0xf3/0x210 [ 75.009778][ T5327] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 75.012327][ T5327] [ 75.012327][ T5327] other info that might help us debug this: [ 75.012327][ T5327] [ 75.016393][ T5327] Chain exists of: [ 75.016393][ T5327] kn->active#5 --> &nvdimm_namespace_key --> &disk->open_mutex [ 75.016393][ T5327] [ 75.021922][ T5327] Possible unsafe locking scenario: [ 75.021922][ T5327] [ 75.025034][ T5327] CPU0 CPU1 [ 75.027125][ T5327] ---- ---- [ 75.029344][ T5327] lock(&disk->open_mutex); [ 75.031292][ T5327] lock(&nvdimm_namespace_key); [ 75.034323][ T5327] lock(&disk->open_mutex); [ 75.037142][ T5327] lock(kn->active#5); [ 75.038860][ T5327] [ 75.038860][ T5327] *** DEADLOCK *** [ 75.038860][ T5327] [ 75.041879][ T5327] 1 lock held by syz.0.0/5327: [ 75.043842][ T5327] #0: ffff88801f1b0358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_del_partition+0x25/0xe0 [ 75.047800][ T5327] [ 75.047800][ T5327] stack backtrace: [ 75.050229][ T5327] CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 Not tainted 6.15.0-rc3-syzkaller-00032-ga79be02bba5c #0 PREEMPT(full) [ 75.050243][ T5327] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 [ 75.050251][ T5327] Call Trace: [ 75.050259][ T5327] [ 75.050265][ T5327] dump_stack_lvl+0x241/0x360 [ 75.050285][ T5327] ? __pfx_dump_stack_lvl+0x10/0x10 [ 75.050300][ T5327] ? __pfx__printk+0x10/0x10 [ 75.050314][ T5327] ? print_lock+0x171/0x1a0 [ 75.050331][ T5327] print_circular_bug+0x2e1/0x300 [ 75.050342][ T5327] check_noncircular+0x142/0x160 [ 75.050354][ T5327] validate_chain+0xa69/0x24e0 [ 75.050365][ T5327] ? check_path+0x21/0x40 [ 75.050374][ T5327] ? check_noncircular+0xee/0x160 [ 75.050384][ T5327] ? lockdep_unlock+0x8d/0x120 [ 75.050397][ T5327] __lock_acquire+0xad5/0xd80 [ 75.050412][ T5327] ? up_write+0x1ab/0x590 [ 75.050422][ T5327] lock_acquire+0x116/0x2f0 [ 75.050434][ T5327] ? __kernfs_remove+0x336/0x570 [ 75.050448][ T5327] kernfs_drain+0x275/0x5e0 [ 75.050458][ T5327] ? __kernfs_remove+0x336/0x570 [ 75.050470][ T5327] ? __pfx_kernfs_drain+0x10/0x10 [ 75.050484][ T5327] __kernfs_remove+0x336/0x570 [ 75.050496][ T5327] kernfs_remove_by_name_ns+0xad/0x130 [ 75.050508][ T5327] device_del+0x56c/0x9b0 [ 75.050522][ T5327] ? __pfx_device_del+0x10/0x10 [ 75.050533][ T5327] ? kobject_put+0x446/0x480 [ 75.050545][ T5327] drop_partition+0x11b/0x180 [ 75.050562][ T5327] bdev_del_partition+0xb0/0xe0 [ 75.050576][ T5327] blkpg_do_ioctl+0x1fe/0x490 [ 75.050590][ T5327] ? __pfx_blkpg_do_ioctl+0x10/0x10 [ 75.050605][ T5327] ? __might_fault+0xaa/0x120 [ 75.050618][ T5327] blkdev_ioctl+0x6ba/0x710 [ 75.050629][ T5327] ? __pfx_blkdev_ioctl+0x10/0x10 [ 75.050640][ T5327] ? __pfx_blkdev_ioctl+0x10/0x10 [ 75.050650][ T5327] __se_sys_ioctl+0xf1/0x160 [ 75.050664][ T5327] do_syscall_64+0xf3/0x210 [ 75.050674][ T5327] ? clear_bhb_loop+0x45/0xa0 [ 75.050686][ T5327] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 75.050698][ T5327] RIP: 0033:0x7fd03518e969 [ 75.050710][ T5327] Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 [ 75.050718][ T5327] RSP: 002b:00007fd036073038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 75.050730][ T5327] RAX: ffffffffffffffda RBX: 00007fd0353b5fa0 RCX: 00007fd03518e969 [ 75.050737][ T5327] RDX: 00002000000001c0 RSI: 0000000000001269 RDI: 0000000000000003 [ 75.050745][ T5327] RBP: 00007fd035210ab1 R08: 0000000000000000 R09: 0000000000000000 [ 75.050752][ T5327] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 75.050759][ T5327] R13: 0000000000000000 R14: 00007fd0353b5fa0 R15: 00007ffc49e6e338 [ 75.050769][ T5327]