From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Tokarev Subject: Re: sata_nv and RAID1 Date: Mon, 13 Jun 2005 15:57:49 +0400 Message-ID: <42AD74BD.8050704@tls.msk.ru> References: <200506111613.42962.dvadell@lantech.com.ar> <20050611192606.GA4055@pentafluge.infradead.org> <42AB49BC.50104@tls.msk.ru> <42AD2B85.30303@pobox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <42AD2B85.30303@pobox.com> Sender: linux-raid-owner@vger.kernel.org To: Jeff Garzik Cc: "Diego M. Vadell" , linux-raid@vger.kernel.org List-Id: linux-raid.ids Jeff Garzik wrote: [linux I/O layer loops forever on SATA drive unplug; SATA hotplug is unsupported yet] >> It isn't hotPLUG -- it's hotUNplug. Happens when drive is dying for > > Same difference to me: both require new code. Jeff, I didn't want to blame you or anyone else (just in case if that wasn't clear). Instead, I just wanted to understand what's the current state of the whole thing. I know SATA hotplug is unsupported, and some code has to be written for that to work. But I don't know if hotUNplugging and error handling comes together. That is, is there a difference between real drive failure (and oh, there are alot of various failure scenarios too, from bad block, including a drive dying completely during normal operations as if there wa no drive at all, up to unplugging the cable by a mistake) and such hot- UN-plugging? Will current code notice and properly propagate I/O errors on the drive, or drive dying? If some errors are propagated properly now, Where's the "boundary" between I/O errors (implemented) and hotplug (not implemented)? This all is quite important IMHO. Without proper error handling (if I/O errors are "blacked" by that "boundary" too), linux SATA subsystem isn't ready for production, and people should not rely on it *now*. /mjt