From: NeilBrown Date: Mon, 15 Dec 2014 01:56:58 +0000 (+1100) Subject: md/bitmap: protect clearing of ->bitmap by mddev->lock X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=978a7a47cae79ae7a7b5a1e80bfcaef6ee700312;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git md/bitmap: protect clearing of ->bitmap by mddev->lock This makes it safe to inspect the struct while holding only the spinlock. Signed-off-by: NeilBrown --- diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index 1695ee5f3ffc..3424b1915fc4 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -1619,7 +1619,9 @@ void bitmap_destroy(struct mddev *mddev) return; mutex_lock(&mddev->bitmap_info.mutex); + spin_lock(&mddev->lock); mddev->bitmap = NULL; /* disconnect from the md device */ + spin_unlock(&mddev->lock); mutex_unlock(&mddev->bitmap_info.mutex); if (mddev->thread) mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT; diff --git a/drivers/md/md.h b/drivers/md/md.h index e41559dccdc9..8770308a8052 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -392,6 +392,7 @@ struct mddev { * clearing MD_CHANGE_* * in_sync - and related safemode and MD_CHANGE changes * pers (also protected by reconfig_mutex and pending IO). + * clearing ->bitmap */ spinlock_t lock; wait_queue_head_t sb_wait; /* for waiting on superblock updates */