Hello Tejun, Am 22.07.2012 19:31, schrieb Tejun Heo:> > I haven't consulted SAT but it seems like a bug in SAS driver or > firmware. If it's a driver bug, we better fix it there. If a > firmware bug, working around those is one of major roles of drivers, > so I think setting allow_restart is fine. as it turns out my workaround (setting allow_restart=1) isn't all that useful after all. There are no more i/o errors because the drive just never goes to standby mode anymore (at least 'hdparm -y /dev/sda' does not seem to have any effect anymore). I don't really understand why - do sas drives ever get to standby mode? (they have allow_restart=1 set by default) And is this desired or expected behavior for sata disk on sas controllers? For the moment the only way for me to have my sata drives sleeping without i/o errors is to revert your original commit (85ef06d1d252f6a2e73b678591ab71caad4667bb - tested with kernels 3.1.10, 3.4.4, 3.4.5, 3.4.6 and 3.5.0) -- Matthias P.S. I hope I'm not getting on everybody's nerves here (especially yours Tejun) -- 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
