6.1-stable review patch. If anyone has any objections, please let me know.
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From: Damien Le Moal dlemoal@kernel.org
commit 626b13f015e080e434b1dee9a0c116ddbf4fb695 upstream.
Commit ff48b37802e5 ("scsi: Do not attempt to rescan suspended devices") modified scsi_rescan_device() to avoid attempting rescanning a suspended device. However, the modification added a check to verify that a SCSI device is in the running state without checking if the device request queue (in the case of block device) is also running, thus allowing the exectuion of internal requests. Without checking the device request queue, commit ff48b37802e5 fix is incomplete and deadlocks on resume can still happen. Use blk_queue_pm_only() to check if the device request queue allows executing commands in addition to checking the SCSI device state.
Reported-by: Petr Tesarik petr@tesarici.cz Fixes: ff48b37802e5 ("scsi: Do not attempt to rescan suspended devices") Cc: stable@vger.kernel.org Tested-by: Petr Tesarik petr@tesarici.cz Reviewed-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Damien Le Moal dlemoal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/scsi/scsi_scan.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)
--- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -1619,12 +1619,13 @@ int scsi_rescan_device(struct scsi_devic device_lock(dev);
/* - * Bail out if the device is not running. Otherwise, the rescan may - * block waiting for commands to be executed, with us holding the - * device lock. This can result in a potential deadlock in the power - * management core code when system resume is on-going. + * Bail out if the device or its queue are not running. Otherwise, + * the rescan may block waiting for commands to be executed, with us + * holding the device lock. This can result in a potential deadlock + * in the power management core code when system resume is on-going. */ - if (sdev->sdev_state != SDEV_RUNNING) { + if (sdev->sdev_state != SDEV_RUNNING || + blk_queue_pm_only(sdev->request_queue)) { ret = -EWOULDBLOCK; goto unlock; }