3.18-stable review patch. If anyone has any objections, please let me know.
------------------ From: Hannes Reinecke <[email protected]> commit e791ce27c3f6a1d3c746fd6a8f8e36c9540ec6f9 upstream. Once the reserved page array is unused we can reset the 'res_in_use' state; here we can do a lazy update without holding the mutex as we only need to check against concurrent access, not concurrent release. [mkp: checkpatch] Fixes: 1bc0eb044615 ("scsi: sg: protect accesses to 'reserved' page array") Signed-off-by: Hannes Reinecke <[email protected]> Reviewed-by: Johannes Thumshirn <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Signed-off-by: Martin K. Petersen <[email protected]> Cc: Todd Poynor <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/scsi/sg.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -2098,6 +2098,8 @@ sg_unlink_reserve(Sg_fd * sfp, Sg_reques req_schp->sglist_len = 0; sfp->save_scat_len = 0; srp->res_used = 0; + /* Called without mutex lock to avoid deadlock */ + sfp->res_in_use = 0; } static Sg_request *
