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_error.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'drivers/scsi/scsi_error.c') diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index ecc07dab893d..ac3196420435 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -1628,11 +1628,17 @@ static void scsi_eh_offline_sdevs(struct list_head *work_q, struct list_head *done_q) { struct scsi_cmnd *scmd, *next; + struct scsi_device *sdev; list_for_each_entry_safe(scmd, next, work_q, eh_entry) { sdev_printk(KERN_INFO, scmd->device, "Device offlined - " "not ready after error recovery\n"); - scsi_device_set_state(scmd->device, SDEV_OFFLINE); + sdev = scmd->device; + + mutex_lock(&sdev->state_mutex); + scsi_device_set_state(sdev, SDEV_OFFLINE); + mutex_unlock(&sdev->state_mutex); + scsi_eh_finish_cmd(scmd, done_q); } return; -- cgit v1.2.3