syzbot ci has tested the following series
[v1] block/blk-mq: fix RT kernel performance regressions https://lore.kernel.org/all/20251220110241.8435-1-ionut.nechita@windriver.co... * [PATCH 1/2] block/blk-mq: fix RT kernel regression with queue_lock in hot path * [PATCH 2/2] block/blk-mq: convert blk_mq_cpuhp_lock to raw_spinlock for RT
and found the following issues: * BUG: sleeping function called from invalid context in __cpuhp_state_add_instance * BUG: sleeping function called from invalid context in __cpuhp_state_remove_instance
Full report is available here: https://ci.syzbot.org/series/632f4721-6256-44fd-83f5-bf439d5f33f9
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BUG: sleeping function called from invalid context in __cpuhp_state_add_instance
tree: torvalds URL: https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux base: dd9b004b7ff3289fb7bae35130c0a5c0537266af arch: amd64 compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 config: https://ci.syzbot.org/builds/9ad1c682-13b1-4626-b61a-a2156384698d/config C repro: https://ci.syzbot.org/findings/f999a055-07f3-4d7a-acfd-8bc0be61e2ec/c_repro syz repro: https://ci.syzbot.org/findings/f999a055-07f3-4d7a-acfd-8bc0be61e2ec/syz_repr...
BUG: sleeping function called from invalid context at ./include/linux/percpu-rwsem.h:51 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5982, name: syz.0.17 preempt_count: 1, expected: 0 RCU nest depth: 0, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [<0000000000000000>] 0x0 CPU: 1 UID: 0 PID: 5982 Comm: syz.0.17 Tainted: G W syzkaller #0 PREEMPT(full) Tainted: [W]=WARN Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 __might_resched+0x495/0x610 kernel/sched/core.c:8827 percpu_down_read_internal include/linux/percpu-rwsem.h:51 [inline] percpu_down_read include/linux/percpu-rwsem.h:77 [inline] cpus_read_lock+0x1b/0x160 kernel/cpu.c:491 __cpuhp_state_add_instance+0x19/0x40 kernel/cpu.c:2454 cpuhp_state_add_instance_nocalls include/linux/cpuhotplug.h:401 [inline] __blk_mq_add_cpuhp block/blk-mq.c:3858 [inline] blk_mq_add_hw_queues_cpuhp+0x19a/0x250 block/blk-mq.c:3906 blk_mq_realloc_hw_ctxs block/blk-mq.c:4611 [inline] blk_mq_init_allocated_queue+0x366/0x1350 block/blk-mq.c:4635 blk_mq_alloc_queue block/blk-mq.c:4416 [inline] __blk_mq_alloc_disk+0x1f0/0x340 block/blk-mq.c:4459 loop_add+0x411/0xad0 drivers/block/loop.c:2050 loop_control_ioctl+0x128/0x5a0 drivers/block/loop.c:2216 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1dc598f7c9 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 RSP: 002b:00007ffff2134d08 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f1dc5be5fa0 RCX: 00007f1dc598f7c9 RDX: 00000000004080f9 RSI: 0000000000004c80 RDI: 0000000000000003 RBP: 00007f1dc59f297f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1dc5be5fa0 R14: 00007f1dc5be5fa0 R15: 0000000000000003 </TASK>
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BUG: sleeping function called from invalid context in __cpuhp_state_remove_instance
tree: torvalds URL: https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux base: dd9b004b7ff3289fb7bae35130c0a5c0537266af arch: amd64 compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 config: https://ci.syzbot.org/builds/9ad1c682-13b1-4626-b61a-a2156384698d/config C repro: https://ci.syzbot.org/findings/f39691bc-570a-4163-9791-31ce10e18fb6/c_repro syz repro: https://ci.syzbot.org/findings/f39691bc-570a-4163-9791-31ce10e18fb6/syz_repr...
BUG: sleeping function called from invalid context at ./include/linux/percpu-rwsem.h:51 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5975, name: syz.0.17 preempt_count: 1, expected: 0 RCU nest depth: 0, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [<0000000000000000>] 0x0 CPU: 0 UID: 0 PID: 5975 Comm: syz.0.17 Tainted: G W syzkaller #0 PREEMPT(full) Tainted: [W]=WARN Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 __might_resched+0x495/0x610 kernel/sched/core.c:8827 percpu_down_read_internal include/linux/percpu-rwsem.h:51 [inline] percpu_down_read include/linux/percpu-rwsem.h:77 [inline] cpus_read_lock+0x1b/0x160 kernel/cpu.c:491 __cpuhp_state_remove_instance+0x77/0x2e0 kernel/cpu.c:2565 cpuhp_state_remove_instance_nocalls include/linux/cpuhotplug.h:502 [inline] __blk_mq_remove_cpuhp+0x140/0x1a0 block/blk-mq.c:3835 blk_mq_remove_cpuhp block/blk-mq.c:3844 [inline] blk_mq_exit_hw_queues block/blk-mq.c:3974 [inline] blk_mq_exit_queue+0xe8/0x380 block/blk-mq.c:4670 __del_gendisk+0x832/0x9e0 block/genhd.c:774 del_gendisk+0xe8/0x160 block/genhd.c:823 loop_remove+0x42/0xc0 drivers/block/loop.c:2121 loop_control_remove drivers/block/loop.c:2180 [inline] loop_control_ioctl+0x4ac/0x5a0 drivers/block/loop.c:2218 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f911d78f7c9 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 RSP: 002b:00007ffd4f0e1fb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f911d9e5fa0 RCX: 00007f911d78f7c9 RDX: 0000000000000006 RSI: 0000000000004c81 RDI: 0000000000000003 RBP: 00007f911d7f297f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f911d9e5fa0 R14: 00007f911d9e5fa0 R15: 0000000000000003 </TASK>
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If these findings have caused you to resend the series or submit a separate fix, please add the following tag to your commit message: Tested-by: syzbot@syzkaller.appspotmail.com
--- This report is generated by a bot. It may contain errors. syzbot ci engineers can be reached at syzkaller@googlegroups.com.