Testing with Loopback I found, that after a Loopback LUN
has executed a TMR, I can no longer unlink the LUN.
The rm command hangs in transport_clear_lun_ref() at
wait_for_completion(&lun->lun_shutdown_comp)
The reason is, that transport_lun_remove_cmd() is not
called at the end of target_tmr_work().
It seems, that in other fabrics this call happens implicitly
when the fabric drivers call transport_generic_free_cmd()
during their ->queue_tm_rsp().
Unfortunately Loopback seems to not comply to the common way
of calling transport_generic_free_cmd() from ->queue_*().
Instead it calls transport_generic_free_cmd() from its
->check_stop_free() only.
But the ->check_stop_free() is called by
transport_cmd_check_stop_to_fabric() after it has reset the
se_cmd->se_lun pointer.
Therefore the following transport_generic_free_cmd() skips the
transport_lun_remove_cmd().
So this patch re-adds the transport_lun_remove_cmd() at the end
of target_tmr_work(), which was removed during commit
2c9fa49e100f962af988f1c0529231bf14905cda
"scsi: target/core: Make ABORT and LUN RESET handling synchronous"
For fabrics using transport_generic_free_cmd() in the usual way
the double call to transport_lun_remove_cmd() doesn't harm, as
transport_lun_remove_cmd() checks for this situation and does
not release lun_ref twice.
Fixes: 2c9fa49e100f ("scsi: target/core: Make ABORT and LUN RESET handling synchronous")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Bodo Stroesser <bstroesser@xxxxxxxxxxxxxx>
Tested-by: Bryant G. Ly <bryangly@xxxxxxxxx>
Reviewed-by: Bart van Assche <bvanassche@xxxxxxx>
---
v2:
- Resend of the same patch with added tags "Fixes:",
"Cc: stable@.." and "Reviewed-by:"
drivers/target/target_core_transport.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 594b724bbf79..264a822c0bfa 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -3350,6 +3350,7 @@ static void target_tmr_work(struct work_struct *work)
cmd->se_tfo->queue_tm_rsp(cmd);
+ transport_lun_remove_cmd(cmd);
transport_cmd_check_stop_to_fabric(cmd);
return;
--
2.12.3
