From 0db6ca8a5e1ea585795db3643ec7d50fc8cb1aff Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Fri, 2 Jun 2017 14:21:55 -0700 Subject: scsi: Protect SCSI device state changes with a mutex Serializing SCSI device state changes avoids that two state changes can occur concurrently, e.g. the state changes in scsi_target_block() and __scsi_remove_device(). This serialization is essential to make patch "Make __scsi_remove_device go straight from BLOCKED to DEL" work reliably. Enable this mechanism for all scsi_target_*block() callers but not for the scsi_internal_device_unblock() calls from the mpt3sas driver because that driver can call scsi_internal_device_unblock() from atomic context. Signed-off-by: Bart Van Assche Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Johannes Thumshirn Signed-off-by: Martin K. Petersen --- drivers/scsi/scsi_transport_srp.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'drivers/scsi/scsi_transport_srp.c') diff --git a/drivers/scsi/scsi_transport_srp.c b/drivers/scsi/scsi_transport_srp.c index 3c5d89852e9f..f617021c94f7 100644 --- a/drivers/scsi/scsi_transport_srp.c +++ b/drivers/scsi/scsi_transport_srp.c @@ -554,11 +554,12 @@ int srp_reconnect_rport(struct srp_rport *rport) * invoking scsi_target_unblock() won't change the state of * these devices into running so do that explicitly. */ - spin_lock_irq(shost->host_lock); - __shost_for_each_device(sdev, shost) + shost_for_each_device(sdev, shost) { + mutex_lock(&sdev->state_mutex); if (sdev->sdev_state == SDEV_OFFLINE) sdev->sdev_state = SDEV_RUNNING; - spin_unlock_irq(shost->host_lock); + mutex_unlock(&sdev->state_mutex); + } } else if (rport->state == SRP_RPORT_RUNNING) { /* * srp_reconnect_rport() has been invoked with fast_io_fail -- cgit v1.2.3-70-g09d2