From 96e56055a2f0961ac1161c31ba1ef1e6a9f7d6ff Mon Sep 17 00:00:00 2001 From: Bodo Stroesser Date: Wed, 13 May 2020 17:34:43 +0200 Subject: [PATCH] scsi: target: Put lun_ref at end of tmr processing commit f2e6b75f6ee82308ef7b00f29e71e5f1c6b3d52a upstream. 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 2c9fa49e100f ("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. Link: https://lore.kernel.org/r/20200513153443.3554-1-bstroesser@ts.fujitsu.com Fixes: 2c9fa49e100f ("scsi: target/core: Make ABORT and LUN RESET handling synchronous") Cc: stable@vger.kernel.org Tested-by: Bryant G. Ly Reviewed-by: Bart van Assche Signed-off-by: Bodo Stroesser Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman --- 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 d542e26ca56a..7c78a5d02c08 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -3336,6 +3336,7 @@ 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;