From db58915fcaf3d24b64fe2c34cc15b5596b9a81bb Mon Sep 17 00:00:00 2001
From: Thomas Huth <thuth@redhat.com>
Date: Fri, 8 Jul 2022 20:49:01 +0200
Subject: [PATCH 14/17] pc-bios/s390-ccw/virtio-blkdev: Request the right
feature bits
RH-Author: Thomas Huth <thuth@redhat.com>
RH-MergeRequest: 106: pc-bios/s390-ccw: Fix boot from disks with 4k sectors that do not have the typical DASD geometry
RH-Commit: [9/10] 9dcd8c2f659f366f9487ab6473d1f0d7778b40a7 (thuth/qemu-kvm-cs9)
RH-Bugzilla: 2098077
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Acked-by: David Hildenbrand <david@redhat.com>
RH-Acked-by: Cornelia Huck <cohuck@redhat.com>
Bugzilla: http://bugzilla.redhat.com/2098077
commit 9125a314cca4a1838b09305a87d8efb98f80ab67
Author: Thomas Huth <thuth@redhat.com>
Date: Mon Jul 4 13:19:01 2022 +0200
pc-bios/s390-ccw/virtio-blkdev: Request the right feature bits
The virtio-blk code uses the block size and geometry fields in the
config area. According to the virtio-spec, these have to be negotiated
with the right feature bits during initialization, otherwise they
might not be available. QEMU is so far very forgiving and always
provides them, but we should not rely on this behavior, so let's
better request them properly via the VIRTIO_BLK_F_GEOMETRY and
VIRTIO_BLK_F_BLK_SIZE feature bits.
Message-Id: <20220704111903.62400-11-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
pc-bios/s390-ccw/virtio-blkdev.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/pc-bios/s390-ccw/virtio-blkdev.c b/pc-bios/s390-ccw/virtio-blkdev.c
index c175b66a47..8271c47296 100644
--- a/pc-bios/s390-ccw/virtio-blkdev.c
+++ b/pc-bios/s390-ccw/virtio-blkdev.c
@@ -13,6 +13,9 @@
#include "virtio.h"
#include "virtio-scsi.h"
+#define VIRTIO_BLK_F_GEOMETRY (1 << 4)
+#define VIRTIO_BLK_F_BLK_SIZE (1 << 6)
+
static int virtio_blk_read_many(VDev *vdev, ulong sector, void *load_addr,
int sec_num)
{
@@ -223,6 +226,7 @@ int virtio_blk_setup_device(SubChannelId schid)
{
VDev *vdev = virtio_get_device();
+ vdev->guest_features[0] = VIRTIO_BLK_F_GEOMETRY | VIRTIO_BLK_F_BLK_SIZE;
vdev->schid = schid;
virtio_setup_ccw(vdev);
--
2.31.1