From: NeilBrown Date: Wed, 31 May 2006 04:27:13 +0000 (-0700) Subject: [PATCH] md: Fix badness in sysfs_notify caused by md_new_event X-Git-Tag: v2.6.17-rc6~60 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c331eb04b995ad276a7ece4608326f1db4e137d8;p=linux-2.6 [PATCH] md: Fix badness in sysfs_notify caused by md_new_event From: NeilBrown If an error is reported by a drive in a RAID array (which is done via bi_end_io - in interrupt context), we call md_error and md_new_event which calls sysfs_notify. However sysfs_notify grabs a mutex and so cannot be called in interrupt context. This patch just creates a variant of md_new_event which avoids the sysfs call, and uses that. A better fix for later is to arrange for the event to be called from user-context. Note: avoiding the sysfs call isn't a problem as an error will not, by itself, modify the sync_action attribute. (We do still need to wake_up(&md_event_waiters) as an error by itself will modify /proc/mdstat). Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/md/md.c b/drivers/md/md.c index ec802913f9..f19b874753 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -167,6 +167,15 @@ void md_new_event(mddev_t *mddev) } EXPORT_SYMBOL_GPL(md_new_event); +/* Alternate version that can be called from interrupts + * when calling sysfs_notify isn't needed. + */ +void md_new_event_inintr(mddev_t *mddev) +{ + atomic_inc(&md_event_count); + wake_up(&md_event_waiters); +} + /* * Enables to iterate over all existing md arrays * all_mddevs_lock protects this list. @@ -4149,7 +4158,7 @@ void md_error(mddev_t *mddev, mdk_rdev_t *rdev) set_bit(MD_RECOVERY_INTR, &mddev->recovery); set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); md_wakeup_thread(mddev->thread); - md_new_event(mddev); + md_new_event_inintr(mddev); } /* seq_file implementation /proc/mdstat */