PR/60182 CVS commit: src/sys/dev/pci

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

The following reply was made to PR kern/60182; it has been noted by GNATS.

From: "Taylor R Campbell" <riastradh%netbsd.org@localhost>
To: gnats-bugs%gnats.NetBSD.org@localhost
Cc: 
Subject: PR/60182 CVS commit: src/sys/dev/pci
Date: Fri, 22 May 2026 14:38:51 +0000

 Module Name:	src
 Committed By:	riastradh
 Date:		Fri May 22 14:38:51 UTC 2026
 
 Modified Files:
 	src/sys/dev/pci: ld_virtio.c
 
 Log Message:
 ld@virtio: Guard virtio_dequeue by virtio_vq_is_enqueued.
 
 After triggering the DMA operation, or any previous virtio_dequeue,
 virtio_vq_is_enqueued issues the necessary bus_dmamap_sync for
 virtio_dequeue to observe any potential (new) result.
 
 Normally this happens inside virtio(4) (in virtio_vq_intr) between
 interrupt delivery and calling the virtqueue's done callback.  But
 polling mode I/O operations (and dump operations) don't take that
 path, so it is necessary to call virtio_vq_is_enqueued explicitly.
 
 PR kern/60182: ld@virtio sometimes hangs up
 
 
 To generate a diff of this commit:
 cvs rdiff -u -r1.47 -r1.48 src/sys/dev/pci/ld_virtio.c
 
 Please note that diffs are not public domain; they are subject to the
 copyright notices on the relevant files.