On Fri, 2014-01-17 at 05:21 -0500, Tejun Heo wrote: > Hello, > > On Fri, Jan 17, 2014 at 11:16:49AM +0100, Oliver Neukum wrote: > > The START-STOP may result in an error. What do you do in that case? > > At least for libata, worrying about suspend/resume failures don't make > whole lot of sense. If suspend failed, just proceed with suspend. If > the device can't be woken up afterwards, that's that.
The specific worry is the writeback cache. If the flush fails and we power down with dirty blocks in the cache, those blocks are lost but the filesystem still thinks they're committed. I think as long as you're using flush barriers on your system, this isn't a problem, but if you're not using barriers, it can lead to undetected corruption that blows up later. If it were a choice between suspend my laptop and save my data, I'd choose the latter. But the question is do we care ... perhaps we can just say you have to use flush barriers if you want to suspend. James -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
