From: Adrian Hunter adrian.hunter@intel.com
commit af4edb1d50c6d1044cb34bc43621411b7ba2cffe upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/scsi/scsi_error.c | 9 +++++++-- drivers/scsi/sd.c | 6 ++++-- include/scsi/scsi_device.h | 1 + 3 files changed, 12 insertions(+), 4 deletions(-)
--- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -483,8 +483,13 @@ static void scsi_report_sense(struct scs
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) { --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -3754,7 +3754,8 @@ static int sd_suspend_common(struct devi 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) { @@ -3776,7 +3777,8 @@ static int sd_suspend_common(struct devi }
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) --- 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 */