From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 47701] When too many disks fall out at the same time, RCU hangs Date: Sun, 7 Oct 2012 02:20:43 +0000 (UTC) Message-ID: <20121007022043.E4EB711FC43@bugzilla.kernel.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: Received: from mail.kernel.org ([198.145.19.201]:43626 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751343Ab2JGCUr (ORCPT ); Sat, 6 Oct 2012 22:20:47 -0400 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 956EB201DE for ; Sun, 7 Oct 2012 02:20:46 +0000 (UTC) Received: from bugzilla.kernel.org (bugzilla.kernel.org [198.145.19.217]) by mail.kernel.org (Postfix) with ESMTP id 3A589201DD for ; Sun, 7 Oct 2012 02:20:44 +0000 (UTC) In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org https://bugzilla.kernel.org/show_bug.cgi?id=47701 Joe Lawrence changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |joe.lawrence@stratus.com --- Comment #2 from Joe Lawrence 2012-10-07 02:20:43 --- Stratus noticed a similar crash (hang actually) earlier this week when removing a single SAS disk as part of a RAID 1 MD mirror. In our instance, the all CPUs were idle, except one that was running scsi_target_reap and another waiting on RCU synchronize_sched. Since the former function was stuck in some loop, RCU stalled and the machine wedged. Another Stratus engineer noticed patch [1], and once applied to our kernel, MD/mpt2sas disk removal no longer hung the machine. [1] [SCSI] scsi_remove_target: fix softlockup regression on hot remove https://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commit;h=bc3f02a795d3b4faa99d37390174be2a75d091bd -- Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug.