Errors are reported through printk. In the upstream kernel this is the spot where an error would be detected and reported for a bad sd_resume: drivers/scsi/sd.c:3061 if (res) { sd_printk(KERN_WARNING, sdkp, "START_STOP FAILED\n"); sd_print_result(sdkp, res); if (driver_byte(res) & DRIVER_SENSE) sd_print_sense_hdr(sdkp, &sshdr); } So it would print out the device id with a message that the start_stop failed, and then optionally print out the sense buffer if it was supplied. Todd Brandt Linux Kernel Developer OTC, Hillsboro OR https://opensource.intel.com/linux-wiki/ToddBrandt ________________________________________ From: Oliver Neukum [oneukum@xxxxxxx] Sent: Friday, August 02, 2013 10:05 AM To: Brandt, Todd E Cc: linux-ide@xxxxxxxxxxxxxxx; linux-scsi@xxxxxxxxxxxxxxx Subject: Re: [PATCH] Hard disk S3 resume time optimization On Fri, 2013-08-02 at 16:41 +0000, Brandt, Todd E wrote: > Do you mean in terms of debug after a failure? I can resubmit the patch with the scsi_sense_hdr buffer still in place. I just wanted to keep the first draft simple to get the concept across. How are errors reported? Regards Oliver -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html