Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756657AbYFYO7t (ORCPT ); Wed, 25 Jun 2008 10:59:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751953AbYFYO7j (ORCPT ); Wed, 25 Jun 2008 10:59:39 -0400 Received: from rtsoft3.corbina.net ([85.21.88.6]:2595 "EHLO buildserver.ru.mvista.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751921AbYFYO7j (ORCPT ); Wed, 25 Jun 2008 10:59:39 -0400 Date: Wed, 25 Jun 2008 18:59:37 +0400 From: Anton Vorontsov To: Sergei Shtylyov Cc: Ingo Molnar , linux-ide@vger.kernel.org, Bartlomiej Zolnierkiewicz , Alan Cox , linux-kernel@vger.kernel.org, Thomas Gleixner , Steven Rostedt , Daniel Walker Subject: Re: [PATCH -rt] ide: fix interrupts processing issue with preempt-able hardirqs Message-ID: <20080625145937.GA2382@polina.dev.rtsoft.ru> Reply-To: avorontsov@ru.mvista.com References: <20080623234037.GA6793@polina.dev.rtsoft.ru> <20080623235141.GB17297@elte.hu> <20080624000016.GA12547@polina.dev.rtsoft.ru> <20080625123431.GA25452@polina.dev.rtsoft.ru> <486244FF.8060805@ru.mvista.com> <20080625142249.GA21630@polina.dev.rtsoft.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Disposition: inline In-Reply-To: <20080625142249.GA21630@polina.dev.rtsoft.ru> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1886 Lines: 49 On Wed, Jun 25, 2008 at 06:22:49PM +0400, Anton Vorontsov wrote: > On Wed, Jun 25, 2008 at 05:15:43PM +0400, Sergei Shtylyov wrote: > > Hello. > > > > Anton Vorontsov wrote: > > > >>>>> IDE interrupt handler relies on the fact that, if necessary, > >>>>> hardirqs will re-trigger on ISR exit. With fully preemtable IRQs > >>>>> this seems to be not true, since if hardirq thread is currently > >>>>> running, and the same IRQ raised again, then this IRQ will be > >>>>> simply lost. > > > >>>> actually no, that should not happen - if -rt loses an IRQ then > >>>> something broke in the threaded IRQ code. It's supposed to be a > >>>> drop-in, compatible IRQ flow with no driver changes needed. > > > >>> ..just as I thought, the bug somewhere deeper... heh. > > > >> Ok, a bit more investigation showed that this is indeed not RT specific > >> per see, but issue emerges only on RT-style IRQ handlers + alim15x3 IDE > >> controller (for example, PDC20269 works ok). > > > > Does it happen only with ATAPI devices also or with ATA disks too? > > So far I own two ATAPI devices, IDE disks are quire rare nowadays, > should find one. ;-) [...] > >> Also, further testing showed that this issue isn't drive-specific, i.e. > >> with a delay inserted before the unmask_irq(), the bug shows with any > >> drive I have. > > > > So, "shit happens" even with the ATA drives? > > Will try as soon as I'll get one. Thanks for the drive, and the result is: hda: irq timeout: status=0x58 { DriveReady SeekComplete DataRequest } ide: failed opcode was: unknown -- Anton Vorontsov email: cbouatmailru@gmail.com irc://irc.freenode.net/bd2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/