Re: [PATCH] fix: scsi: srp_reconnect_rport: unbalanced scsi_block_targets/scsi_target_unblock

Hi WenTao,

kernel test robot noticed the following build warnings:

[auto build test WARNING on jejb-scsi/for-next]
[also build test WARNING on mkp-scsi/for-next linus/master v7.2-rc6 next-20260805]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/WenTao-Liang/fix-scsi-srp_reconnect_rport-unbalanced-scsi_block_targets-scsi_target_unblock/20260805-214818
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi.git for-next
patch link:    https://lore.kernel.org/r/20260626161402.55116-1-vulab%40iscas.ac.cn
patch subject: [PATCH] fix: scsi: srp_reconnect_rport: unbalanced   scsi_block_targets/scsi_target_unblock
config: x86_64-kexec (https://download.01.org/0day-ci/archive/20260806/[email protected]/config)
compiler: clang version 22.1.8 (https://github.com/llvm/llvm-project ca7933e47d3a3451d81e72ac174dcb5aa28b59d1)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260806/[email protected]/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

All warnings (new ones prefixed by >>):

>> drivers/scsi/scsi_transport_srp.c:553:3: warning: misleading indentation; statement is not part of the previous 'if' [-Wmisleading-indentation]
     553 |                 blocked = true;
         |                 ^
   drivers/scsi/scsi_transport_srp.c:545:2: note: previous statement is here
     545 |         if (rport->state != SRP_RPORT_FAIL_FAST && rport->state != SRP_RPORT_LOST)
         |         ^
   1 warning generated.


vim +/if +553 drivers/scsi/scsi_transport_srp.c

   509	
   510	/**
   511	 * srp_reconnect_rport() - reconnect to an SRP target port
   512	 * @rport: SRP target port.
   513	 *
   514	 * Blocks SCSI command queueing before invoking reconnect() such that
   515	 * queuecommand() won't be invoked concurrently with reconnect() from outside
   516	 * the SCSI EH. This is important since a reconnect() implementation may
   517	 * reallocate resources needed by queuecommand().
   518	 *
   519	 * Notes:
   520	 * - This function neither waits until outstanding requests have finished nor
   521	 *   tries to abort these. It is the responsibility of the reconnect()
   522	 *   function to finish outstanding commands before reconnecting to the target
   523	 *   port.
   524	 * - It is the responsibility of the caller to ensure that the resources
   525	 *   reallocated by the reconnect() function won't be used while this function
   526	 *   is in progress. One possible strategy is to invoke this function from
   527	 *   the context of the SCSI EH thread only. Another possible strategy is to
   528	 *   lock the rport mutex inside each SCSI LLD callback that can be invoked by
   529	 *   the SCSI EH (the scsi_host_template.eh_*() functions and also the
   530	 *   scsi_host_template.queuecommand() function).
   531	 */
   532	int srp_reconnect_rport(struct srp_rport *rport)
   533	{
   534		struct Scsi_Host *shost = rport_to_shost(rport);
   535		struct srp_internal *i = to_srp_internal(shost->transportt);
   536		struct scsi_device *sdev;
   537		int res;
   538		bool blocked = false;
   539	
   540		pr_debug("SCSI host %s\n", dev_name(&shost->shost_gendev));
   541	
   542		res = mutex_lock_interruptible(&rport->mutex);
   543		if (res)
   544			goto out;
   545		if (rport->state != SRP_RPORT_FAIL_FAST && rport->state != SRP_RPORT_LOST)
   546			/*
   547			 * sdev state must be SDEV_TRANSPORT_OFFLINE, transition
   548			 * to SDEV_BLOCK is illegal. Calling scsi_target_unblock()
   549			 * later is ok though, scsi_internal_device_unblock_nowait()
   550			 * treats SDEV_TRANSPORT_OFFLINE like SDEV_BLOCK.
   551			 */
   552			scsi_block_targets(shost, &shost->shost_gendev);
 > 553			blocked = true;
   554		res = rport->state != SRP_RPORT_LOST ? i->f->reconnect(rport) : -ENODEV;
   555		pr_debug("%s (state %d): transport.reconnect() returned %d\n",
   556			 dev_name(&shost->shost_gendev), rport->state, res);
   557		if (res == 0) {
   558			cancel_delayed_work(&rport->fast_io_fail_work);
   559			cancel_delayed_work(&rport->dev_loss_work);
   560	
   561			rport->failed_reconnects = 0;
   562			srp_rport_set_state(rport, SRP_RPORT_RUNNING);
   563			if (blocked)
   564				scsi_target_unblock(&shost->shost_gendev, SDEV_RUNNING);
   565			/*
   566			 * If the SCSI error handler has offlined one or more devices,
   567			 * invoking scsi_target_unblock() won't change the state of
   568			 * these devices into running so do that explicitly.
   569			 */
   570			shost_for_each_device(sdev, shost) {
   571				mutex_lock(&sdev->state_mutex);
   572				if (sdev->sdev_state == SDEV_OFFLINE)
   573					sdev->sdev_state = SDEV_RUNNING;
   574				mutex_unlock(&sdev->state_mutex);
   575			}
   576		} else if (rport->state == SRP_RPORT_RUNNING) {
   577			/*
   578			 * srp_reconnect_rport() has been invoked with fast_io_fail
   579			 * and dev_loss off. Mark the port as failed and start the TL
   580			 * failure timers if these had not yet been started.
   581			 */
   582			__rport_fail_io_fast(rport);
   583			__srp_start_tl_fail_timers(rport);
   584		} else if (rport->state != SRP_RPORT_BLOCKED) {
   585			if (blocked)
   586				scsi_target_unblock(&shost->shost_gendev,
   587					    SDEV_TRANSPORT_OFFLINE);
   588		}
   589		mutex_unlock(&rport->mutex);
   590	
   591	out:
   592		return res;
   593	}
   594	EXPORT_SYMBOL(srp_reconnect_rport);
   595