syzbot has found a reproducer for the following issue on: HEAD commit: f31817cbcf48 Add linux-next specific files for 20231116 git tree: linux-next console+strace: https://syzkaller.appspot.com/x/log.txt?x=14fa5a48e80000 kernel config: https://syzkaller.appspot.com/x/.config?x=f59345f1d0a928c dashboard link: https://syzkaller.appspot.com/bug?extid=cef555184e66963dabc2 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13fd7920e80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17d80920e80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/987488cb251e/disk-f31817cb.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/6d4a82d8bd4b/vmlinux-f31817cb.xz kernel image: https://storage.googleapis.com/syzbot-assets/fc43dee9cb86/bzImage-f31817cb.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+cef555184e66963dabc2@xxxxxxxxxxxxxxxxxxxxxxxxx ======================================================== WARNING: possible irq lock inversion dependency detected 6.7.0-rc1-next-20231116-syzkaller #0 Not tainted -------------------------------------------------------- swapper/0/0 just changed the state of lock: ffffffff8cff86b8 (css_set_lock){..-.}-{2:2}, at: put_css_set kernel/cgroup/cgroup-internal.h:208 [inline] ffffffff8cff86b8 (css_set_lock){..-.}-{2:2}, at: put_css_set kernel/cgroup/cgroup-internal.h:196 [inline] ffffffff8cff86b8 (css_set_lock){..-.}-{2:2}, at: cgroup_free+0x7c/0x1d0 kernel/cgroup/cgroup.c:6748 but this lock took another, SOFTIRQ-unsafe lock in the past: (&sighand->siglock){+.+.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sighand->siglock); local_irq_disable(); lock(css_set_lock); lock(&sighand->siglock); <Interrupt> lock(css_set_lock); *** DEADLOCK *** 2 locks held by swapper/0/0: #0: ffffffff8cfacf40 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8cfacf40 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2152 [inline] #0: ffffffff8cfacf40 (rcu_callback){....}-{0:0}, at: rcu_core+0x7cc/0x16b0 kernel/rcu/tree.c:2431 #1: ffffffff8ce58800 (put_task_map-wait-type-override){+...}-{3:3}, at: put_task_struct include/linux/sched/task.h:135 [inline] #1: ffffffff8ce58800 (put_task_map-wait-type-override){+...}-{3:3}, at: put_task_struct include/linux/sched/task.h:123 [inline] #1: ffffffff8ce58800 (put_task_map-wait-type-override){+...}-{3:3}, at: delayed_put_task_struct+0x21e/0x2d0 kernel/exit.c:227 the shortest dependencies between 2nd lock and 1st lock: -> (&sighand->siglock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:530 [inline] ptrace_set_stopped kernel/ptrace.c:391 [inline] ptrace_attach+0x401/0x650 kernel/ptrace.c:478 __do_sys_ptrace+0x204/0x230 kernel/ptrace.c:1290 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x62/0x6a SOFTIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:530 [inline] ptrace_set_stopped kernel/ptrace.c:391 [inline] ptrace_attach+0x401/0x650 kernel/ptrace.c:478 __do_sys_ptrace+0x204/0x230 kernel/ptrace.c:1290 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x62/0x6a INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0x36/0x50 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] calculate_sigpending+0x44/0xa0 kernel/signal.c:197 ret_from_fork+0x23/0x80 arch/x86/kernel/process.c:143 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 } ... key at: [<ffffffff90b49f80>] __key.341+0x0/0x40 ... acquired at: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 __lock_task_sighand+0xc2/0x340 kernel/signal.c:1422 lock_task_sighand include/linux/sched/signal.h:748 [inline] cgroup_freeze_task+0x80/0x190 kernel/cgroup/freezer.c:160 cgroup_freezer_migrate_task+0x1b7/0x3a0 kernel/cgroup/freezer.c:257 cgroup_migrate_execute+0x2d3/0x1230 kernel/cgroup/cgroup.c:2580 cgroup_update_dfl_csses+0x51b/0x640 kernel/cgroup/cgroup.c:3068 cgroup_apply_control kernel/cgroup/cgroup.c:3308 [inline] cgroup_subtree_control_write+0xb94/0xed0 kernel/cgroup/cgroup.c:3453 cgroup_file_write+0x209/0x7c0 kernel/cgroup/cgroup.c:4092 kernfs_fop_write_iter+0x33f/0x500 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:2021 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x64d/0xdf0 fs/read_write.c:584 ksys_write+0x12f/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x62/0x6a -> (css_set_lock){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 put_css_set kernel/cgroup/cgroup-internal.h:208 [inline] put_css_set kernel/cgroup/cgroup-internal.h:196 [inline] cgroup_free+0x7c/0x1d0 kernel/cgroup/cgroup.c:6748 __put_task_struct+0x10b/0x3d0 kernel/fork.c:992 put_task_struct include/linux/sched/task.h:136 [inline] put_task_struct include/linux/sched/task.h:123 [inline] delayed_put_task_struct+0x22c/0x2d0 kernel/exit.c:227 rcu_do_batch kernel/rcu/tree.c:2158 [inline] rcu_core+0x828/0x16b0 kernel/rcu/tree.c:2431 __do_softirq+0x216/0x8d5 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb5/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0x83/0x500 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:215 [inline] do_idle+0x314/0x3f0 kernel/sched/idle.c:312 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:410 rest_init+0x16f/0x2b0 init/main.c:730 arch_call_rest_init+0x13/0x30 init/main.c:827 start_kernel+0x39e/0x480 init/main.c:1072 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:555 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x166/0x16b INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0x36/0x50 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] cgroup_setup_root+0x62c/0xa00 kernel/cgroup/cgroup.c:2138 cgroup_init+0x23f/0x1100 kernel/cgroup/cgroup.c:6120 start_kernel+0x385/0x480 init/main.c:1063 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:555 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x166/0x16b } ... key at: [<ffffffff8cff86b8>] css_set_lock+0x18/0x60 ... acquired at: mark_usage kernel/locking/lockdep.c:4566 [inline] __lock_acquire+0x13c2/0x3b10 kernel/locking/lockdep.c:5090 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 put_css_set kernel/cgroup/cgroup-internal.h:208 [inline] put_css_set kernel/cgroup/cgroup-internal.h:196 [inline] cgroup_free+0x7c/0x1d0 kernel/cgroup/cgroup.c:6748 __put_task_struct+0x10b/0x3d0 kernel/fork.c:992 put_task_struct include/linux/sched/task.h:136 [inline] put_task_struct include/linux/sched/task.h:123 [inline] delayed_put_task_struct+0x22c/0x2d0 kernel/exit.c:227 rcu_do_batch kernel/rcu/tree.c:2158 [inline] rcu_core+0x828/0x16b0 kernel/rcu/tree.c:2431 __do_softirq+0x216/0x8d5 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb5/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0x83/0x500 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:215 [inline] do_idle+0x314/0x3f0 kernel/sched/idle.c:312 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:410 rest_init+0x16f/0x2b0 init/main.c:730 arch_call_rest_init+0x13/0x30 init/main.c:827 start_kernel+0x39e/0x480 init/main.c:1072 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:555 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x166/0x16b stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.7.0-rc1-next-20231116-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_irq_inversion_bug.part.0+0x3e1/0x590 kernel/locking/lockdep.c:4079 print_irq_inversion_bug kernel/locking/lockdep.c:4032 [inline] check_usage_forwards kernel/locking/lockdep.c:4110 [inline] mark_lock_irq kernel/locking/lockdep.c:4242 [inline] mark_lock+0x570/0xc50 kernel/locking/lockdep.c:4677 mark_usage kernel/locking/lockdep.c:4566 [inline] __lock_acquire+0x13c2/0x3b10 kernel/locking/lockdep.c:5090 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 put_css_set kernel/cgroup/cgroup-internal.h:208 [inline] put_css_set kernel/cgroup/cgroup-internal.h:196 [inline] cgroup_free+0x7c/0x1d0 kernel/cgroup/cgroup.c:6748 __put_task_struct+0x10b/0x3d0 kernel/fork.c:992 put_task_struct include/linux/sched/task.h:136 [inline] put_task_struct include/linux/sched/task.h:123 [inline] delayed_put_task_struct+0x22c/0x2d0 kernel/exit.c:227 rcu_do_batch kernel/rcu/tree.c:2158 [inline] rcu_core+0x828/0x16b0 kernel/rcu/tree.c:2431 __do_softirq+0x216/0x8d5 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb5/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1076 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline] RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:113 Code: 08 ed c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 65 48 8b 05 a8 8a 82 75 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 78 0a b9 00 fb f4 <fa> c3 0f 1f 40 00 0f b6 47 08 3c 01 74 0b 3c 02 74 05 8b 7f 04 eb RSP: 0018:ffffffff8cc07d68 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8a8117f5 RDX: 0000000000000001 RSI: ffff8880156c2800 RDI: ffff8880156c2864 RBP: ffff8880156c2864 R08: 0000000000000001 R09: ffffed1017306dbd R10: ffff8880b9836deb R11: 0000000000000000 R12: ffff888147ac4000 R13: ffffffff8db1a520 R14: 0000000000000000 R15: 0000000000000000 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0x83/0x500 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:215 [inline] do_idle+0x314/0x3f0 kernel/sched/idle.c:312 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:410 rest_init+0x16f/0x2b0 init/main.c:730 arch_call_rest_init+0x13/0x30 init/main.c:827 start_kernel+0x39e/0x480 init/main.c:1072 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:555 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x166/0x16b </TASK> ---------------- Code disassembly (best guess): 0: 08 ed or %ch,%ch 2: c3 ret 3: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1) a: 00 00 00 00 e: 66 90 xchg %ax,%ax 10: 65 48 8b 05 a8 8a 82 mov %gs:0x75828aa8(%rip),%rax # 0x75828ac0 17: 75 18: 48 8b 00 mov (%rax),%rax 1b: a8 08 test $0x8,%al 1d: 75 0c jne 0x2b 1f: 66 90 xchg %ax,%ax 21: 0f 00 2d 78 0a b9 00 verw 0xb90a78(%rip) # 0xb90aa0 28: fb sti 29: f4 hlt * 2a: fa cli <-- trapping instruction 2b: c3 ret 2c: 0f 1f 40 00 nopl 0x0(%rax) 30: 0f b6 47 08 movzbl 0x8(%rdi),%eax 34: 3c 01 cmp $0x1,%al 36: 74 0b je 0x43 38: 3c 02 cmp $0x2,%al 3a: 74 05 je 0x41 3c: 8b 7f 04 mov 0x4(%rdi),%edi 3f: eb .byte 0xeb --- If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing.
