From cf8fcc97c173618534874046d2f29d4135cf2441 Mon Sep 17 00:00:00 2001
Message-Id: <cf8fcc97c173618534874046d2f29d4135cf2441@dist-git>
From: Peter Krempa <pkrempa@redhat.com>
Date: Fri, 8 Dec 2017 10:27:03 +0100
Subject: [PATCH] qemu: blockjob: Reset disk source index after pivot

Since we are re-detecting the backing chain after pivoting to the active
block commit target (or block copy target) the disk index needs to be
reset to 0. This is necessary since we move a member of the backing
chain to disk->src but clear indexes only starting from
disk->src->backingStore. The freshly detected images have indexes
starting from 1, but since we've pivoted into an image which was
previously a backing store it would have a non-0 index.
The lookup function would then return the top of the chain for queries
like 'vda[1]' instead of the first backing store.

This problem will not be present once we keep the disk indexes stable.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1519745
(cherry picked from commit fac8724ceb371f962d5d185c639456a34d71659e)
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 src/qemu/qemu_blockjob.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/qemu/qemu_blockjob.c b/src/qemu/qemu_blockjob.c
index c1b46f7d0a..afc05f161c 100644
--- a/src/qemu/qemu_blockjob.c
+++ b/src/qemu/qemu_blockjob.c
@@ -165,6 +165,7 @@ qemuBlockJobEventProcess(virQEMUDriverPtr driver,
         disk->mirror = NULL;
         disk->mirrorState = VIR_DOMAIN_DISK_MIRROR_STATE_NONE;
         disk->mirrorJob = VIR_DOMAIN_BLOCK_JOB_TYPE_UNKNOWN;
+        disk->src->id = 0;
         ignore_value(qemuDomainDetermineDiskChain(driver, vm, disk,
                                                   true, true));
         ignore_value(qemuBlockNodeNamesDetect(driver, vm, asyncJob));
-- 
2.15.1