• Russell King's avatar
    [BLOCK] Fix oops on removal of SD/MMC card · 56cf6504
    Russell King authored
    The block layer keeps a reference (driverfs_dev) to the struct
    device associated with the block device, and uses it internally
    for generating uevents in block_uevent.
    
    Block device uevents include umounting the partition, which can
    occur after the backing device has been removed.
    
    Unfortunately, this reference is not counted.  This means that
    if the struct device is removed from the device tree, the block
    layers reference will become stale.
    
    Guard against this by holding a reference to the struct device
    in add_disk(), and only drop the reference when we're releasing
    the gendisk kobject - in other words when we can be sure that no
    further uevents will be generated for this block device.
    Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
    Acked-by: default avatarJens Axboe <axboe@suse.de>
    56cf6504
genhd.c 16.7 KB