From d0de492ff3ffc1faaa6856a7e12665449039cdea Mon Sep 17 00:00:00 2001
From: Alasdair Kergon <agk@redhat.com>
Date: Fri, 6 Jun 2008 11:12:50 +0000
Subject: [PATCH] cope with volatile vginfo in vg_read

---
 lib/cache/lvmcache.c    | 3 +++
 lib/metadata/metadata.c | 8 +++++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/lib/cache/lvmcache.c b/lib/cache/lvmcache.c
index 33b029566..77382d4c3 100644
--- a/lib/cache/lvmcache.c
+++ b/lib/cache/lvmcache.c
@@ -243,6 +243,9 @@ struct lvmcache_vginfo *vginfo_from_vgname(const char *vgname, const char *vgid)
 {
 	struct lvmcache_vginfo *vginfo;
 
+	if (!vgname)
+		return vginfo_from_vgid(vgid);
+
 	if (!_vgname_hash)
 		return NULL;
 
diff --git a/lib/metadata/metadata.c b/lib/metadata/metadata.c
index ff05d7c12..d385814a8 100644
--- a/lib/metadata/metadata.c
+++ b/lib/metadata/metadata.c
@@ -1476,6 +1476,8 @@ static int _update_pv_list(struct list *all_pvs, struct volume_group *vg)
  * and call vg_read again).
  *
  * If precommitted is set, use precommitted metadata if present.
+ *
+ * Either of vgname or vgid may be NULL.
  */
 static struct volume_group *_vg_read(struct cmd_context *cmd,
 				     const char *vgname,
@@ -1522,6 +1524,10 @@ static struct volume_group *_vg_read(struct cmd_context *cmd,
 		}
 	}
 
+	/* Now determine the correct vgname if none was supplied */
+	if (!vgname && !(vgname = vgname_from_vgid(cmd->mem, vgid)))
+		return_NULL;
+
 	if (use_precommitted && !(fmt->features & FMT_PRECOMMIT))
 		use_precommitted = 0;
 
@@ -1752,7 +1758,7 @@ static struct volume_group *_vg_read_by_vgid(struct cmd_context *cmd,
 	/* Is corresponding vgname already cached? */
 	if ((vginfo = vginfo_from_vgid(vgid)) &&
 	    vginfo->vgname && !is_orphan_vg(vginfo->vgname)) {
-		if ((vg = _vg_read(cmd, vginfo->vgname, vgid,
+		if ((vg = _vg_read(cmd, NULL, vgid,
 				   &consistent, precommitted)) &&
 		    !strncmp((char *)vg->id.uuid, vgid, ID_LEN)) {
 			if (!consistent) {