Re: [syzbot] [kernel?] WARNING in gic_handle_irq

[Marc Zyngier <maz@kernel.org>]

On Tue, 25 Aug 2026 20:14:33 +0100,
syzbot <syzbot+1e7fd72b380dc57b82b8@syzkaller.appspotmail.com> wrote:
> 
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    21d6ac051080 Merge branch 'for-next/core' into for-kernelci
> git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
> console output: https://syzkaller.appspot.com/x/log.txt?x=12f93e79580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=d1128bc53f2ef7f3
> dashboard link: https://syzkaller.appspot.com/bug?extid=1e7fd72b380dc57b82b8
> compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
> userspace arch: arm64
> 
> Unfortunately, I don't have any reproducer for this issue yet.
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/88380e2ddcb9/disk-21d6ac05.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/5dba5c2896b7/vmlinux-21d6ac05.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/52ac739e37e0/Image-21d6ac05.gz.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+1e7fd72b380dc57b82b8@syzkaller.appspotmail.com
> 
> ------------[ cut here ]------------
> Unexpected interrupt (irqnr 8194)

This appears to be triggered by an LPI (most probably an MSI) firing,
but by the time we handle it, there is nothing to left handle it in
the corresponding irq domain.

The console log contains the following bits:

[   73.897524][ T1057] nvme nvme0: Identify namespace failed (-5)
[   73.906396][   T39] nvme nvme0: 2/0/0 default/read/poll queues
[   73.907149][ T7866] nvme nvme0: resetting controller
[   73.923113][  T866] usb 1-1: new high-speed USB device number 5 using dummy_hcd
[   73.943439][  T866] usb 1-1: device descriptor read/8, error -71
[   73.986096][    C0] ------------[ cut here ]------------
[   73.986109][    C0] Unexpected interrupt (irqnr 8194)

which indicates that some stuff is being reset/failing close to that
time. With the right timing (made easier with virtualisation), it
isn't impossible to think that the interrupt has already reached the
handling CPU while another CPU tears it down.

Not sure there is anything to do here other than tone down the
warning.

	M.

-- 
Jazz isn't dead. It just smells funny.