File 0001-Remove-container-should-wait-for-an-array-to-release.patch of Package mdadm.7533
From c922221e2522fd24f86e5a0de0bfba60b14353c0 Mon Sep 17 00:00:00 2001
From: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
Date: Thu, 21 Jul 2016 09:59:42 +0200
Subject: [PATCH] Remove: container should wait for an array to release a drive
A 'faulty' drive is being removed from a container after it has been
released by an array, however there is a race there. The drive is
released asynchronously by a monitor but sometimes it doesn't happen
before container checks it. It results in a container refusing to remove
a drive as it still seems to be a part of some array.
It seems 'ping_monitor' could be a solution here to assure monitor has
had a chance to process the events, however it doesn't resolve the
problem - sometimes an array has to request a release of the drive few
times (as the array is busy) and single 'ping_monitor' call is not
sufficient. As there is no way to query monitor progress, it forces us
to retry a check several times before an error is returned.
Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
---
Manage.c | 41 ++++++++++++++++++++++++++++-------------
1 file changed, 28 insertions(+), 13 deletions(-)
--- a/Manage.c
+++ b/Manage.c
@@ -1139,19 +1139,34 @@ int Manage_remove(struct supertype *tst,
*/
if (rdev == 0)
ret = -1;
- else
- ret = sysfs_unique_holder(devnm, rdev);
- if (ret == 0) {
- pr_err("%s is not a member, cannot remove.\n",
- dv->devname);
- close(lfd);
- return -1;
- }
- if (ret >= 2) {
- pr_err("%s is still in use, cannot remove.\n",
- dv->devname);
- close(lfd);
- return -1;
+ else {
+ /*
+ * The drive has already been set to 'faulty', however
+ * monitor might not have had time to process it and the
+ * drive might still have an entry in the 'holders'
+ * directory. Try a few times to avoid a false error
+ */
+ int count = 20;
+
+ do {
+ ret = sysfs_unique_holder(devnm, rdev);
+ if (ret < 2)
+ break;
+ usleep(100 * 1000); /* 100ms */
+ } while (--count > 0);
+
+ if (ret == 0) {
+ pr_err("%s is not a member, cannot remove.\n",
+ dv->devname);
+ close(lfd);
+ return -1;
+ }
+ if (ret >= 2) {
+ pr_err("%s is still in use, cannot remove.\n",
+ dv->devname);
+ close(lfd);
+ return -1;
+ }
}
}
/* FIXME check that it is a current member */