• Ronny Hegewald's avatar
    rbd: require stable pages if message data CRCs are enabled · bae818ee
    Ronny Hegewald authored
    rbd requires stable pages, as it performs a crc of the page data before
    they are send to the OSDs.
    
    But since kernel 3.9 (patch 1d1d1a76
    "mm: only enforce stable page writes if the backing device requires
    it") it is not assumed anymore that block devices require stable pages.
    
    This patch sets the necessary flag to get stable pages back for rbd.
    
    In a ceph installation that provides multiple ext4 formatted rbd
    devices "bad crc" messages appeared regularly (ca 1 message every 1-2
    minutes on every OSD that provided the data for the rbd) in the
    OSD-logs before this patch. After this patch this messages are pretty
    much gone (only ca 1-2 / month / OSD).
    
    Cc: stable@vger.kernel.org # 3.9+, needs backporting
    Signed-off-by: default avatarRonny Hegewald <Ronny.Hegewald@online.de>
    [idryomov@gmail.com: require stable pages only in crc case, changelog]
    Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
    bae818ee
rbd.c 146 KB