| From 1ffa7d12a15fdc4f1bbed59bf5d3292ac2b574b3 Mon Sep 17 00:00:00 2001 |
| From: Jeffrey Cody <jcody@redhat.com> |
| Date: Mon, 12 Jun 2017 14:46:56 +0200 |
| Subject: [PATCH 11/13] block: fix external snapshot abort permission error |
| |
| RH-Author: Jeffrey Cody <jcody@redhat.com> |
| Message-id: <14e6e82657b93fb6bec16eddce051ced36db5ff9.1497278737.git.jcody@redhat.com> |
| Patchwork-id: 75593 |
| O-Subject: [RHEV-7.4 qemu-kvm-rhev PATCH 1/1] block: fix external snapshot abort permission error |
| Bugzilla: 1447184 |
| RH-Acked-by: Kevin Wolf <kwolf@redhat.com> |
| RH-Acked-by: Max Reitz <mreitz@redhat.com> |
| RH-Acked-by: John Snow <jsnow@redhat.com> |
| |
| In external_snapshot_abort(), we try to undo what was done in |
| external_snapshot_prepare() calling bdrv_replace_node() to swap the |
| nodes back. However, we receive a permissions error as writers are |
| blocked on the old node, which is now the new node backing file. |
| |
| An easy fix (initially suggested by Kevin Wolf) is to call |
| bdrv_set_backing_hd() on the new node, to set the backing node to NULL. |
| |
| Signed-off-by: Jeff Cody <jcody@redhat.com> |
| Reviewed-by: Eric Blake <eblake@redhat.com> |
| Signed-off-by: Kevin Wolf <kwolf@redhat.com> |
| (cherry picked from commit 719fc28c80a22ab9f1533d775bae09c14442bbbe) |
| Signed-off-by: Jeff Cody <jcody@redhat.com> |
| Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com> |
| |
| blockdev.c | 4 ++++ |
| 1 file changed, 4 insertions(+) |
| |
| diff --git a/blockdev.c b/blockdev.c |
| index 4432143..a3a0731 100644 |
| |
| |
| @@ -1847,7 +1847,11 @@ static void external_snapshot_abort(BlkActionState *common) |
| DO_UPCAST(ExternalSnapshotState, common, common); |
| if (state->new_bs) { |
| if (state->overlay_appended) { |
| + bdrv_ref(state->old_bs); /* we can't let bdrv_set_backind_hd() |
| + close state->old_bs; we need it */ |
| + bdrv_set_backing_hd(state->new_bs, NULL, &error_abort); |
| bdrv_replace_node(state->new_bs, state->old_bs, &error_abort); |
| + bdrv_unref(state->old_bs); /* bdrv_replace_node() ref'ed old_bs */ |
| } |
| } |
| } |
| -- |
| 1.8.3.1 |
| |