pve-qemu/debian/patches/pve/0046-block-io-accept-NULL-q...

32 lines
1023 B
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Stefan Reiter <s.reiter@proxmox.com>
Date: Tue, 2 Mar 2021 16:11:54 +0100
Subject: [PATCH] block/io: accept NULL qiov in bdrv_pad_request
Some operations, e.g. block-stream, perform reads while discarding the
results (only copy-on-read matters). In this case they will pass NULL as
the target QEMUIOVector, which will however trip bdrv_pad_request, since
it wants to extend its passed vector.
Simply check for NULL and do nothing, there's no reason to pad the
target if it will be discarded anyway.
---
block/io.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/block/io.c b/block/io.c
index ca2dca3007..a9e70a4f91 100644
--- a/block/io.c
+++ b/block/io.c
@@ -1731,6 +1731,10 @@ static int bdrv_pad_request(BlockDriverState *bs,
{
int ret;
+ if (!qiov) {
+ return 0;
+ }
+
bdrv_check_qiov_request(*offset, *bytes, *qiov, *qiov_offset, &error_abort);
if (!bdrv_init_padding(bs, *offset, *bytes, pad)) {