From: Arkadiusz Bubała <arkadiusz.bubala@open-e.com>
Date: Thu, 6 Jul 2017 15:38:24 +0000 (+0200)
Subject: Reschedule processes on -ERESTARTSYS
X-Git-Tag: zfs-0.7.0-rc5~15
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=94b25662c51696ec081494e69efb5896566dede2;p=zfs

Reschedule processes on -ERESTARTSYS

On the single core machine the system may hang when the
spa_namespare_lock acquisition fails in the zvol_first_open
function. It returns -ERESTARTSYS error what causes the
endless loop in __blkdev_get function.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Arkadiusz Bubała <arkadiusz.bubala@open-e.com>
Closes #6283
Closes #6312
---

diff --git a/module/zfs/zvol.c b/module/zfs/zvol.c
index 3e9f004ef..4f1601ec6 100644
--- a/module/zfs/zvol.c
+++ b/module/zfs/zvol.c
@@ -1358,6 +1358,8 @@ out_mutex:
 	mutex_exit(&zv->zv_state_lock);
 	if (drop_suspend)
 		rw_exit(&zv->zv_suspend_lock);
+	if (error == -ERESTARTSYS)
+		schedule();
 
 	return (SET_ERROR(error));
 }