scsi: core: sd: Add silence_suspend flag to suppress some PM messages

Kernel messages produced during runtime PM can cause a never-ending cycle
because user space utilities (e.g. journald or rsyslog) write the messages
back to storage, causing runtime resume, more messages, and so on.

Messages that tell of things that are expected to happen are arguably
unnecessary, so add a flag to suppress them. This flag is used by the UFS
driver.

Link: https://lore.kernel.org/r/20220228113652.970857-2-adrian.hunter@intel.com
Cc: stable@vger.kernel.org
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 9c237b223e63ced8f60cafa9e1edcffabe32c065..fd0827116f5306f6eb8fd28f4ffdb6287a4be893 100644 (file)
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -484,8 +484,13 @@ static void scsi_report_sense(struct scsi_device *sdev,
 
                if (sshdr->asc == 0x29) {
                        evt_type = SDEV_EVT_POWER_ON_RESET_OCCURRED;
-                       sdev_printk(KERN_WARNING, sdev,
-                                   "Power-on or device reset occurred\n");
+                       /*
+                        * Do not print message if it is an expected side-effect
+                        * of runtime PM.
+                        */
+                       if (!sdev->silence_suspend)
+                               sdev_printk(KERN_WARNING, sdev,
+                                           "Power-on or device reset occurred\n");
                }
 
                if (sshdr->asc == 0x2a && sshdr->ascq == 0x01) {

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 2f9d160bc8c21e88596cba17ae7052b32e0e79ea..7a5eb4ebc03667858df13b29d1698717335a3223 100644 (file)
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -3676,7 +3676,8 @@ static int sd_suspend_common(struct device *dev, bool ignore_stop_errors)
                return 0;
 
        if (sdkp->WCE && sdkp->media_present) {
-               sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
+               if (!sdkp->device->silence_suspend)
+                       sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
                ret = sd_sync_cache(sdkp, &sshdr);
 
                if (ret) {
@@ -3698,7 +3699,8 @@ static int sd_suspend_common(struct device *dev, bool ignore_stop_errors)
        }
 
        if (sdkp->device->manage_start_stop) {
-               sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
+               if (!sdkp->device->silence_suspend)
+                       sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
                /* an error is not worth aborting a system sleep */
                ret = sd_start_stop_device(sdkp, 0);
                if (ignore_stop_errors)

diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 647c53b2610514eb5f6c8fa34e8df2261895df8b..57e3e239a1fce64972b82dfa1c43028888edd1e9 100644 (file)
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -206,6 +206,7 @@ struct scsi_device {
        unsigned rpm_autosuspend:1;     /* Enable runtime autosuspend at device
                                         * creation time */
        unsigned ignore_media_change:1; /* Ignore MEDIA CHANGE on resume */
+       unsigned silence_suspend:1;     /* Do not print runtime PM related messages */
 
        unsigned int queue_stopped;     /* request queue is quiesced */
        bool offline_already;           /* Device offline message logged */