Re: [PATCH] virtio: rtc: time out alarm requests

[Peter Hilber]

On Tue, Jul 14, 2026 at 10:43:52AM +0800, GuoHan Zhao wrote:
> RTC class operations run with rtc_device.ops_lock held. The virtio RTC
> alarm requests currently wait without a timeout for the device to return
> their requestq buffers.
> 
> On surprise removal, virtio-pci marks the virtqueues broken before
> unregistering the virtio device. If an alarm request is waiting when the
> device stops responding, viortc_remove() blocks in viortc_class_stop()
> while trying to acquire ops_lock. The request cannot complete and device
> removal hangs until the waiting task is signalled.
> 
> Use the same 60-second timeout as clock read requests for alarm reads,
> alarm programming, and alarm interrupt enable requests. The existing
> message reference counting keeps a timed-out request alive until a late
> response or device teardown.
> 
> Fixes: 9d4f22fd563e ("virtio_rtc: Add RTC class driver")
> Assisted-by: Codex:gpt-5.6-sol
> Signed-off-by: GuoHan Zhao <zhaoguohan@xxxxxxxxxx>

Thanks for the fix!

Reviewed-by: Peter Hilber <peter.hilber@xxxxxxxxxxxxxxxx>