Re: [syzbot] [fuse?] BUG: scheduling while atomic in __synchronize_srcu

[syzbot <syzbot+12b178b7c756664d2518@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
BUG: scheduling while atomic in __synchronize_srcu

BUG: scheduling while atomic: syz.2.40/4121/0x00000002
Modules linked in:
CPU: 0 UID: 0 PID: 4121 Comm: syz.2.40 Not tainted syzkaller #0 PREEMPT 
Hardware name: linux,dummy-virt (DT)
Call trace:
 dump_backtrace arch/arm64/kernel/stacktrace.c:498 [inline] (C)
 show_stack+0x18/0x24 arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x60/0x80 lib/dump_stack.c:120
 dump_stack+0x18/0x24 lib/dump_stack.c:129
 __schedule_bug+0x54/0x78 kernel/sched/core.c:5847
 schedule_debug kernel/sched/core.c:5874 [inline]
 __schedule+0x858/0xd84 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0x34/0x114 kernel/sched/core.c:7008
 schedule_timeout+0xd4/0x110 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common kernel/sched/completion.c:132 [inline]
 wait_for_completion+0x78/0x160 kernel/sched/completion.c:153
 __synchronize_srcu+0x90/0xd0 kernel/rcu/srcutree.c:1496
 synchronize_srcu_expedited+0x24/0x40 kernel/rcu/srcutree.c:1521
 kvm_set_irq_routing+0x204/0x294 virt/kvm/irqchip.c:225
 kvm_vgic_setup_default_irq_routing+0x78/0xc0 arch/arm64/kvm/vgic/vgic-irqfd.c:153
 vgic_init+0x1ac/0x268 arch/arm64/kvm/vgic/vgic-init.c:421
 vgic_lazy_init+0x54/0x6c arch/arm64/kvm/vgic/vgic-init.c:550
 kvm_vgic_inject_irq+0x30/0x12c arch/arm64/kvm/vgic/vgic.c:520
 kvm_timer_update_irq+0x68/0x7c arch/arm64/kvm/arch_timer.c:450
 kvm_timer_vcpu_reset+0xd8/0x1e0 arch/arm64/kvm/arch_timer.c:1036
 kvm_reset_vcpu+0x194/0x360 arch/arm64/kvm/reset.c:268
 kvm_vcpu_set_target arch/arm64/kvm/arm.c:1632 [inline]
 kvm_arch_vcpu_ioctl_vcpu_init arch/arm64/kvm/arm.c:1652 [inline]
 kvm_arch_vcpu_ioctl+0x2e4/0x8c8 arch/arm64/kvm/arm.c:1773
 kvm_vcpu_ioctl+0x4ac/0x8f4 virt/kvm/kvm_main.c:4653
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __arm64_sys_ioctl+0xac/0x104 fs/ioctl.c:583
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x48/0x104 arch/arm64/kernel/syscall.c:49
 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:151
 el0_svc+0x34/0x124 arch/arm64/kernel/entry-common.c:724
 el0t_64_sync_handler+0xa0/0xf0 arch/arm64/kernel/entry-common.c:743
 el0t_64_sync+0x1a4/0x1a8 arch/arm64/kernel/entry.S:596
BUG: scheduling while atomic: syz.2.40/4121/0x00000000
Modules linked in:
CPU: 0 UID: 0 PID: 4121 Comm: syz.2.40 Tainted: G        W           syzkaller #0 PREEMPT 
Tainted: [W]=WARN
Hardware name: linux,dummy-virt (DT)
Call trace:
 dump_backtrace arch/arm64/kernel/stacktrace.c:498 [inline] (C)
 show_stack+0x18/0x24 arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x60/0x80 lib/dump_stack.c:120
 dump_stack+0x18/0x24 lib/dump_stack.c:129
 __schedule_bug+0x54/0x78 kernel/sched/core.c:5847
 schedule_debug kernel/sched/core.c:5874 [inline]
 __schedule+0x858/0xd84 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0x34/0x114 kernel/sched/core.c:7008
 futex_do_wait kernel/futex/waitwake.c:358 [inline]
 __futex_wait+0xf0/0x178 kernel/futex/waitwake.c:687
 futex_wait+0x88/0x118 kernel/futex/waitwake.c:715
 do_futex+0xf8/0x1a0 kernel/futex/syscalls.c:130
 __do_sys_futex kernel/futex/syscalls.c:207 [inline]
 __se_sys_futex kernel/futex/syscalls.c:188 [inline]
 __arm64_sys_futex+0xfc/0x1a0 kernel/futex/syscalls.c:188
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x48/0x104 arch/arm64/kernel/syscall.c:49
 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:151
 el0_svc+0x34/0x124 arch/arm64/kernel/entry-common.c:724
 el0t_64_sync_handler+0xa0/0xf0 arch/arm64/kernel/entry-common.c:743
 el0t_64_sync+0x1a4/0x1a8 arch/arm64/kernel/entry.S:596


Tested on:

commit:         028ef9c9 Linux 7.0
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=132b80ce580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2d08886358f27e8c
dashboard link: https://syzkaller.appspot.com/bug?extid=12b178b7c756664d2518
compiler:       aarch64-linux-gnu-gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: arm64

Note: no patches were applied.