|
|
0a122b |
From d3ec1ceddceff322c71dae8c6efff7bec166aeb8 Mon Sep 17 00:00:00 2001
|
|
|
0a122b |
From: Kevin Wolf <kwolf@redhat.com>
|
|
|
0a122b |
Date: Wed, 8 Jan 2014 19:43:25 +0000
|
|
|
0a122b |
Subject: [PATCH 01/37] block: fix backing file segfault
|
|
|
0a122b |
|
|
|
0a122b |
Message-id: <1392117622-28812-2-git-send-email-kwolf@redhat.com>
|
|
|
0a122b |
Patchwork-id: 57166
|
|
|
0a122b |
O-Subject: [RHEL-7.0 qemu-kvm PATCH v2 01/37] block: fix backing file segfault
|
|
|
0a122b |
Bugzilla: 748906
|
|
|
0a122b |
RH-Acked-by: Laszlo Ersek <lersek@redhat.com>
|
|
|
0a122b |
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
|
|
|
0a122b |
RH-Acked-by: Max Reitz <mreitz@redhat.com>
|
|
|
0a122b |
|
|
|
0a122b |
From: Peter Feiner <peter@gridcentric.ca>
|
|
|
0a122b |
|
|
|
0a122b |
When a backing file is opened such that (1) a protocol is directly
|
|
|
0a122b |
used as the block driver and (2) the block driver has bdrv_file_open,
|
|
|
0a122b |
bdrv_open_backing_file segfaults. The problem arises because
|
|
|
0a122b |
bdrv_open_common returns without setting bd->backing_hd->file.
|
|
|
0a122b |
|
|
|
0a122b |
To effect (1), you seem to have to use the -F flag in qemu-img. There
|
|
|
0a122b |
are several block drivers that satisfy (2), such as "file" and "nbd".
|
|
|
0a122b |
Here are some concrete examples:
|
|
|
0a122b |
|
|
|
0a122b |
#!/bin/bash
|
|
|
0a122b |
|
|
|
0a122b |
echo Test file format
|
|
|
0a122b |
./qemu-img create -f file base.file 1m
|
|
|
0a122b |
./qemu-img create -f qcow2 -F file -o backing_file=base.file\
|
|
|
0a122b |
file-overlay.qcow2
|
|
|
0a122b |
./qemu-img convert -O raw file-overlay.qcow2 file-convert.raw
|
|
|
0a122b |
|
|
|
0a122b |
echo Test nbd format
|
|
|
0a122b |
SOCK=$PWD/nbd.sock
|
|
|
0a122b |
./qemu-img create -f raw base.raw 1m
|
|
|
0a122b |
./qemu-nbd -t -k $SOCK base.raw &
|
|
|
0a122b |
trap "kill $!" EXIT
|
|
|
0a122b |
while ! test -e $SOCK; do sleep 1; done
|
|
|
0a122b |
./qemu-img create -f qcow2 -F nbd -o backing_file=nbd:unix:$SOCK\
|
|
|
0a122b |
nbd-overlay.qcow2
|
|
|
0a122b |
./qemu-img convert -O raw nbd-overlay.qcow2 nbd-convert.raw
|
|
|
0a122b |
|
|
|
0a122b |
Without this patch, the two qemu-img convert commands segfault.
|
|
|
0a122b |
|
|
|
0a122b |
This is a regression that was introduced in v1.7 by
|
|
|
0a122b |
dbecebddfa4932d1c83915bcb9b5ba5984eb91be.
|
|
|
0a122b |
|
|
|
0a122b |
Signed-off-by: Peter Feiner <peter@gridcentric.ca>
|
|
|
0a122b |
Reviewed-by: Max Reitz <mreitz@redhat.com>
|
|
|
0a122b |
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
|
|
|
0a122b |
(cherry picked from commit d80ac658f2caacfb14ea386211c4a9bea0cea280)
|
|
|
0a122b |
|
|
|
0a122b |
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
|
|
|
0a122b |
---
|
|
|
0a122b |
block.c | 8 ++++++--
|
|
|
0a122b |
1 file changed, 6 insertions(+), 2 deletions(-)
|
|
|
0a122b |
---
|
|
|
0a122b |
block.c | 8 ++++++--
|
|
|
0a122b |
1 files changed, 6 insertions(+), 2 deletions(-)
|
|
|
0a122b |
|
|
|
0a122b |
diff --git a/block.c b/block.c
|
|
|
0a122b |
index 1433844..df0adf3 100644
|
|
|
0a122b |
--- a/block.c
|
|
|
0a122b |
+++ b/block.c
|
|
|
0a122b |
@@ -978,8 +978,12 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
|
|
|
0a122b |
error_propagate(errp, local_err);
|
|
|
0a122b |
return ret;
|
|
|
0a122b |
}
|
|
|
0a122b |
- pstrcpy(bs->backing_file, sizeof(bs->backing_file),
|
|
|
0a122b |
- bs->backing_hd->file->filename);
|
|
|
0a122b |
+
|
|
|
0a122b |
+ if (bs->backing_hd->file) {
|
|
|
0a122b |
+ pstrcpy(bs->backing_file, sizeof(bs->backing_file),
|
|
|
0a122b |
+ bs->backing_hd->file->filename);
|
|
|
0a122b |
+ }
|
|
|
0a122b |
+
|
|
|
0a122b |
return 0;
|
|
|
0a122b |
}
|
|
|
0a122b |
|
|
|
0a122b |
--
|
|
|
0a122b |
1.7.1
|
|
|
0a122b |
|