This patch is the same idea as my previous patch for giving /dev/disk/by-{id,path} a chance to exist. Currently libvirt can race with udev creation of /dev/disk/by-{id,path}, so if we fail to open the directory, retry up to 5 seconds. This is only likely to happen on hosts that are: 1) diskless (so /dev/disk/by-{id,path} doesn't exist already), and 2) slow, and/or heavily loaded (meaning that udev can take some time to create the /dev nodes). Based on the feedback from Dan and Jim, I updated the patch to look more like what is elsewhere in libvirt. Signed-off-by: Chris Lalancette <clalance@redhat.com> Index: src/storage_backend.c =================================================================== RCS file: /data/cvs/libvirt/src/storage_backend.c,v retrieving revision 1.29 diff -u -r1.29 storage_backend.c --- a/src/storage_backend.c 17 Nov 2008 11:19:33 -0000 1.29 +++ b/src/storage_backend.c 26 Nov 2008 12:09:36 -0000 @@ -291,6 +291,7 @@ DIR *dh; struct dirent *dent; char *stablepath; + int opentries = 0; /* Short circuit if pool has no target, or if its /dev */ if (pool->def->target.path == NULL || @@ -304,12 +305,17 @@ if (!STRPREFIX(pool->def->target.path, "/dev")) goto ret_strdup; - /* The pool is pointing somewhere like /dev/disk/by-path - * or /dev/disk/by-id, so we need to check all symlinks in - * the target directory and figure out which one points - * to this device node + /* We loop here because /dev/disk/by-{id,path} may not have existed + * before we started this operation, so we have to give it some time to + * get created. */ + reopen: if ((dh = opendir(pool->def->target.path)) == NULL) { + opentries++; + if (errno == ENOENT && opentries < 50) { + usleep(100 * 1000); + goto reopen; + } virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR, _("cannot read dir %s: %s"), pool->def->target.path, @@ -317,6 +323,11 @@ return NULL; } + /* The pool is pointing somewhere like /dev/disk/by-path + * or /dev/disk/by-id, so we need to check all symlinks in + * the target directory and figure out which one points + * to this device node + */ while ((dent = readdir(dh)) != NULL) { if (dent->d_name[0] == '.') continue;