Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756290Ab1DLOHl (ORCPT ); Tue, 12 Apr 2011 10:07:41 -0400 Received: from ironport2-out.teksavvy.com ([206.248.154.181]:62751 "EHLO ironport2-out.pppoe.ca" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755258Ab1DLOHj (ORCPT ); Tue, 12 Apr 2011 10:07:39 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApIBAKpbpE1Ld/sX/2dsb2JhbAAMhD+rUagJkTKBKYFYgXV4BJQK X-IronPort-AV: E=Sophos;i="4.64,195,1301889600"; d="scan'208";a="106078858" Message-ID: <4DA45CA7.9040102@teksavvy.com> Date: Tue, 12 Apr 2011 10:07:35 -0400 From: Mark Lord User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-GB; rv:1.9.2.15) Gecko/20110303 Thunderbird/3.1.9 MIME-Version: 1.0 To: Bruce Stenning CC: "linux-kernel@vger.kernel.org" , "linux-ide@vger.kernel.org" Subject: Re: sata_mv port lockup on hotplug (kernel 2.6.38.2) References: <4D9CD275.9000002@teksavvy.com> <4D9FACC9.7020200@teksavvy.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1598 Lines: 38 On 11-04-12 06:30 AM, Bruce Stenning wrote: > > I have reproduced the issue with the 2.6.32 kernel. Perfect. This means that it probably wasn't broken by somebody else since I last looked at the code two years ago. :) > > In case it is of use, the silicon is rev 09 (i.e. C0 stepping) and I am using > gcc 4.4.2 to build the kernel and modules. "C0" is *good*. > I am currently inserting tracing into 2.6.38.2 to try to work out what is going > on. From mv_write_main_irq_mask I can see that the IRQ for each port is still > enabled, even when ports stop responding. I see interrupts generated when I > hotplug or unplug disks on ports that are not locked up, but no interrupt is > generated at all for the ports that are locked (this is from tracing in > asm_do_IRQ in arch/arm/kernel/irq.c) > > One thing I noticed was that there is no spinlock around the > mv_save_cached_regs/mv_edma_cfg in mv_hardreset (unlike mv_port_start and > mv_port_stop); why is this? The mv_hardreset path is run from a libata-eh thread, and it assumes it has exclusive access to the hardware. But by all means, stuff the spinlock around that pair of calls, just to eliminate any possibility of my mis-thinking it there. I'm going to take a few minutes now and try to re-understand how hot-plug gets "armed" for use, and see if anything cries out at me. Cheers -- 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/