On Sat, Nov 23, 2024 at 06:42:24AM -0800, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 06afb0f36106 Merge tag 'trace-v6.13' of git://git.kernel.o.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=125a81c0580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=95b76860fd16c857 > dashboard link: https://syzkaller.appspot.com/bug?extid=9b145229d11aa73e4571 > 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. This one is supposed to be reproduced 100%, :-( > > -> #0 (fs_reclaim){+.+.}-{0:0}: > check_prev_add kernel/locking/lockdep.c:3161 [inline] > check_prevs_add kernel/locking/lockdep.c:3280 [inline] > validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 > __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 > lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 > __fs_reclaim_acquire mm/page_alloc.c:3851 [inline] > fs_reclaim_acquire+0x88/0x130 mm/page_alloc.c:3865 > might_alloc include/linux/sched/mm.h:318 [inline] > slab_pre_alloc_hook mm/slub.c:4036 [inline] > slab_alloc_node mm/slub.c:4114 [inline] > __kmalloc_cache_noprof+0x3d/0x2c0 mm/slub.c:4290 > kmalloc_noprof include/linux/slab.h:879 [inline] > kzalloc_noprof include/linux/slab.h:1015 [inline] > kobject_uevent_env+0x28b/0x8e0 lib/kobject_uevent.c:540 > set_capacity_and_notify+0x206/0x240 block/genhd.c:95 > loop_set_size drivers/block/loop.c:232 [inline] > loop_set_status+0x584/0x8f0 drivers/block/loop.c:1285 > lo_ioctl+0xcbc/0x1f50 > blkdev_ioctl+0x57d/0x6a0 block/ioctl.c:693 > vfs_ioctl fs/ioctl.c:51 [inline] > __do_sys_ioctl fs/ioctl.c:906 [inline] > __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f Looks one real deadlock because bio_queue_enter() may be called from direct reclaim, which is under blk_mq_freeze_queue(). thanks, Ming
