From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oa2-f11.google.com (mail-oa2-f11.google.com [74.125.231.75]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3C2B33C6600 for ; Tue, 22 Sep 2026 11:54:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.231.75 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790078100; cv=none; b=DvzfFYtm3+MTBp0a19VqkTcWt6l/f4EPzREp/4CZwIiI7d7rfHRaNqwkxWNNEjE9VjAFvTgCMNZdNIsI2s6REfWIRjFMrrBaeAOgqSVMRCB8RwXvfNxVR16FVHBL0MOPqjri/2TZtguYZ6qVb+PHFLyhPryIOKBxRgNCwvA2GiI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790078100; c=relaxed/simple; bh=9Vrz2yJ5IJQ8xZobKroTxgw4W4TDjfkF1IVwe35tFzM=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=Cy6ZHfcErPlWpevt8GSnEh9ttaIju6KTTgXPvhaXaLXFtOXb+YnSkqqO2JY8wcPz64hDK6Hw+5EIBwBcPOSdhN+IQxbxwR54T/f6X4Lfb91AOE6tOjWpJRUFXqxExdMiLG9SJB+f6xQVIir5MecY0wBiavBlH1SDwh16bljMAAA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=74.125.231.75 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oa2-f11.google.com with SMTP id 586e51a60fabf-46a6530ebd4so1339500fac.0 for ; Tue, 22 Sep 2026 04:54:57 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790078097; x=1790682897; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=xz9NsVfFyEQ4ELu4SH9AXjL8muGA26kDetAt0gAOsqY=; b=qH/op6VcUTZPrdj9ucNiW1zYaBSiImZILLK5dgEDxaXMBEREhS5ta9TUYQdINLmirD HzJlE/NTK4yu4+zUEAPcY3ImaVmN+k8FkjBNhDltsSN8PKoZ/DHuWRWfBfDFYLAQ6G6N C+/yT2VlCerAXLq2A4CUF3tY0G1uPg0OcT+Db8U+GJb7neWkPIIie0vEu+RpumDcIOhW LcSy74jMXrlkOzuXAeOclBl3mYGmXEZndPqfbBFBhZCF4Je/DTXyq05SfS1JoGUWV15q 1O5AXuJ05MV4EZkqw549blAIbSgdvIiDu0ew9F+LKp40DL7b+xqnvapt2v7fU+cFSPL4 c3rA== X-Forwarded-Encrypted: i=1; AKwUvBwxnaTtmVzGfN7Y2iEDX7Zzej/q9PJnnHl6KxfEg0HkOCCaFwRaFemJcN9fEK/Pm5azeNSjrY324492nw==@vger.kernel.org X-Gm-Message-State: AFuF++l+ee6N6q+F+Od5V00FsjmehYxm0pOyIi7nkVPoEs58lDyE+yJs gDRVxaoRoTzAIKOrl26fSfqby3NFhC36xhf1xAdXw+SBjXHf4DC5QF3x2gMI6L2mcotNz/pFLxH vdyFurF5o2t5cn6Rm+1eTxZQwaVz/wrYzR/QfTzVH0pyW8/NCTTdD2xCzC+Q= Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:2908:b0:6c9:e0a0:af1d with SMTP id 006d021491bc7-6ca9a643b29mr12002654eaf.26.1790078096876; Tue, 22 Sep 2026 04:54:56 -0700 (PDT) Date: Tue, 22 Sep 2026 04:54:56 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6ab26c90.c68e76dc.23da29.00ab.GAE@google.com> Subject: [syzbot] [block?] possible deadlock in sd_revalidate_disk From: syzbot To: axboe@kernel.dk, dlemoal@kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 9d80aa4617b3 Add linux-next specific files for 20260903 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=175ba915580000 kernel config: https://syzkaller.appspot.com/x/.config?x=b370c26fb58c72f0 dashboard link: https://syzkaller.appspot.com/bug?extid=2e02ccadb3c5522a5c59 compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/84a12994f553/disk-9d80aa46.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/2329deeb3b2b/vmlinux-9d80aa46.xz kernel image: https://storage.googleapis.com/syzbot-assets/689910d8c695/bzImage-9d80aa46.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+2e02ccadb3c5522a5c59@syzkaller.appspotmail.com sd 1:0:0:0: [sdb] Test Unit Ready failed: Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK sd 1:0:0:0: [sdb] Read Capacity(10) failed: Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK sd 1:0:0:0: [sdb] Sense not available. ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ kworker/u8:3/49 is trying to acquire lock: ffffffff8f090420 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:316 [inline] ffffffff8f090420 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:4636 [inline] ffffffff8f090420 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:4974 [inline] ffffffff8f090420 (fs_reclaim){+.+.}-{0:0}, at: __do_kmalloc_node mm/slub.c:5418 [inline] ffffffff8f090420 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_noprof+0xbc/0x710 mm/slub.c:5444 but task is already holding lock: ffff888012ece3b8 (&q->limits_lock){+.+.}-{4:4}, at: queue_limits_start_update include/linux/blkdev.h:1101 [inline] ffff888012ece3b8 (&q->limits_lock){+.+.}-{4:4}, at: sd_revalidate_disk+0xb88/0xb350 drivers/scsi/sd.c:3803 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&q->limits_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x197/0x15a0 kernel/locking/mutex.c:821 queue_limits_start_update include/linux/blkdev.h:1101 [inline] disk_update_zone_resources block/blk-zoned.c:2067 [inline] blk_revalidate_disk_zones+0xad9/0x12e0 block/blk-zoned.c:2375 nvme_mpath_revalidate_zones+0x106/0x1c0 drivers/nvme/host/multipath.c:301 nvme_update_ns_info+0x984/0x1200 drivers/nvme/host/core.c:2622 nvme_alloc_ns drivers/nvme/host/core.c:4284 [inline] nvme_scan_ns+0x2563/0x3640 drivers/nvme/host/core.c:4471 async_run_entry_fn+0x9d/0x430 kernel/async.c:129 process_one_work kernel/workqueue.c:3399 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3482 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3563 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #1 (&q->q_usage_counter(io)#77){++++}-{0:0}: blk_alloc_queue+0x544/0x690 block/blk-core.c:504 __blk_alloc_disk+0xe3/0x1d0 block/genhd.c:1527 nvme_mpath_alloc_disk+0x5c2/0x8b0 drivers/nvme/host/multipath.c:769 nvme_alloc_ns_head drivers/nvme/host/core.c:4043 [inline] nvme_init_ns_head drivers/nvme/host/core.c:4144 [inline] nvme_alloc_ns drivers/nvme/host/core.c:4258 [inline] nvme_scan_ns+0x1e0f/0x3640 drivers/nvme/host/core.c:4471 async_run_entry_fn+0x9d/0x430 kernel/async.c:129 process_one_work kernel/workqueue.c:3399 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3482 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3563 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #0 (fs_reclaim){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3209 [inline] check_prevs_add kernel/locking/lockdep.c:3328 [inline] validate_chain kernel/locking/lockdep.c:3952 [inline] __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 __fs_reclaim_acquire mm/page_alloc.c:4357 [inline] fs_reclaim_acquire+0x71/0x100 mm/page_alloc.c:4371 might_alloc include/linux/sched/mm.h:316 [inline] slab_pre_alloc_hook mm/slub.c:4636 [inline] slab_alloc_node mm/slub.c:4974 [inline] __do_kmalloc_node mm/slub.c:5418 [inline] __kmalloc_noprof+0xbc/0x710 mm/slub.c:5444 _kmalloc_noprof include/linux/slab.h:995 [inline] sd_read_block_zero drivers/scsi/sd.c:3749 [inline] sd_revalidate_disk+0x177d/0xb350 drivers/scsi/sd.c:3817 sd_probe+0x9f3/0x1180 drivers/scsi/sd.c:4101 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x254/0xae0 drivers/base/dd.c:706 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1026 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach_async_helper+0x1e7/0x2b0 drivers/base/dd.c:1055 async_run_entry_fn+0x9d/0x430 kernel/async.c:129 process_one_work kernel/workqueue.c:3399 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3482 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3563 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 other info that might help us debug this: Chain exists of: fs_reclaim --> &q->q_usage_counter(io)#77 --> &q->limits_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->limits_lock); lock(&q->q_usage_counter(io)#77); lock(&q->limits_lock); lock(fs_reclaim); *** DEADLOCK *** locks held by kworker/u8:3/49: 4, last CPU#0: #0: ffff88801bedc940 ((wq_completion)async){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88801bedc940 ((wq_completion)async){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88801bedc940 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3364 [inline] #0: ffff88801bedc940 ((wq_completion)async){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3482 #1: ffffc90000ba7c40 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90000ba7c40 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90000ba7c40 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3364 [inline] #1: ffffc90000ba7c40 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3482 #2: ffff888075d823c0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline] #2: ffff888075d823c0 (&dev->mutex){....}-{4:4}, at: __device_attach_async_helper+0xa4/0x2b0 drivers/base/dd.c:1041 #3: ffff888012ece3b8 (&q->limits_lock){+.+.}-{4:4}, at: queue_limits_start_update include/linux/blkdev.h:1101 [inline] #3: ffff888012ece3b8 (&q->limits_lock){+.+.}-{4:4}, at: sd_revalidate_disk+0xb88/0xb350 drivers/scsi/sd.c:3803 stack backtrace: CPU: 0 UID: 0 PID: 49 Comm: kworker/u8:3 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: async async_run_entry_fn Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2087 check_noncircular+0x12f/0x150 kernel/locking/lockdep.c:2219 check_prev_add kernel/locking/lockdep.c:3209 [inline] check_prevs_add kernel/locking/lockdep.c:3328 [inline] validate_chain kernel/locking/lockdep.c:3952 [inline] __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 __fs_reclaim_acquire mm/page_alloc.c:4357 [inline] fs_reclaim_acquire+0x71/0x100 mm/page_alloc.c:4371 might_alloc include/linux/sched/mm.h:316 [inline] slab_pre_alloc_hook mm/slub.c:4636 [inline] slab_alloc_node mm/slub.c:4974 [inline] __do_kmalloc_node mm/slub.c:5418 [inline] __kmalloc_noprof+0xbc/0x710 mm/slub.c:5444 _kmalloc_noprof include/linux/slab.h:995 [inline] sd_read_block_zero drivers/scsi/sd.c:3749 [inline] sd_revalidate_disk+0x177d/0xb350 drivers/scsi/sd.c:3817 sd_probe+0x9f3/0x1180 drivers/scsi/sd.c:4101 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x254/0xae0 drivers/base/dd.c:706 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1026 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach_async_helper+0x1e7/0x2b0 drivers/base/dd.c:1055 async_run_entry_fn+0x9d/0x430 kernel/async.c:129 process_one_work kernel/workqueue.c:3399 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3482 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3563 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 sd 1:0:0:0: [sdb] 0 512-byte logical blocks: (0 B/0 B) sd 1:0:0:0: [sdb] 0-byte physical blocks sd 1:0:0:0: [sdb] Write Protect is off sd 1:0:0:0: [sdb] Mode Sense: 00 00 00 00 sd 1:0:0:0: [sdb] Asking for cache data failed sd 1:0:0:0: [sdb] Assuming drive cache: write through sd 1:0:0:0: [sdb] Attached SCSI removable disk --- This report is generated by a bot. 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