Hi Nicholas and Bart, On Sun, Apr 02, 2017 at 03:59:05PM -0700, Nicholas A. Bellinger wrote: > On Thu, 2017-03-30 at 10:12 -0700, Bart Van Assche wrote: > > While releasing a command __iscsit_free_cmd() can be called multiple > > times but .iscsit_release_cmd() must be called only once. Hence move > > the .iscsit_release_cmd() call into iscsit_release_cmd(). The latter > > function is only called once per command. The only driver that defines > > the .iscsit_release_cmd() callback is the cxgbit driver so this change > > only affects the cxgbit driver. > > > > Fixes: 7ec811a8e9c3 ("iscsi-target: add void (*iscsit_release_cmd)()") > > Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxxxxxx> > > Cc: Varun Prakash <varun@xxxxxxxxxxx> > > Cc: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> > > Cc: <stable@xxxxxxxxxxxxxxx> > > --- > > drivers/target/iscsi/iscsi_target_util.c | 15 +++++++++------ > > 1 file changed, 9 insertions(+), 6 deletions(-) > > > > Applied to target-pending/for-next, but dropping the stable CC' because > the single caller in cxgbit_release_cmd() is already checking to ensure > resources are only released on the first invocation. > > So it's not a bug-fix. In case of DDP cxgbit driver assigns cmd->se_cmd.t_data_sg to ttinfo->sgl and calls dma_map_sg(), cxgbit_release_cmd() calls dma_unmap_sg(), it needs a valid sg(ttinfo->sgl), before calling iscsit_release_cmd() cmd->se_cmd.t_data_sg gets freed so ttinfo->sgl will not be valid if we move ->iscsit_release_cmd() to iscsit_release_cmd(). Thanks Varun