From patchwork Tue Nov 8 12:14:45 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicholas Piggin X-Patchwork-Id: 692280 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3tCpK46ZBLz9t2T for ; Tue, 8 Nov 2016 23:19:36 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="fH++GWRf"; dkim-atps=neutral Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 3tCpK45T3rzDvSH for ; Tue, 8 Nov 2016 23:19:36 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="fH++GWRf"; dkim-atps=neutral X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Received: from mail-pf0-x244.google.com (mail-pf0-x244.google.com [IPv6:2607:f8b0:400e:c00::244]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3tCpCp3wp6zDvRM for ; Tue, 8 Nov 2016 23:15:02 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="fH++GWRf"; dkim-atps=neutral Received: by mail-pf0-x244.google.com with SMTP id 144so10923796pfv.0 for ; Tue, 08 Nov 2016 04:15:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=H48xtFV8WM4sA4DrpuGmB8xnRxPlQoPDR3TjZ9TIKL4=; b=fH++GWRfYBNP9Y1OLfCg4YP5Zk6/kSG+g4nEDliSSjLIhso536cmt9etCHCqpApnPc djjW+MGF0lF7oqtdd8FzfyQ2C8WZWYm6FFTr6AnapxCjtEKUhl8so//3WtgYMMYp0cwU LGCvzK3kgBh+157nM0dWcxE8jqINgYpc61BfcxvCbuVHGU16mLhDW5JO9FORrWQWprsO 8BqnI3Sg/ZEwNyy5hw+1bub80YGCBQbQg01rt7dIjEI1nXHgFprswjXeud+bvZEXp8TB pzvGLJ9iRcTs8Iv3ZL1UwrZOjk1r/tUjTJ8Mk1c3pMr95ZURCCHnIRbrjz1MBtnGHeeh POqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=H48xtFV8WM4sA4DrpuGmB8xnRxPlQoPDR3TjZ9TIKL4=; b=Wjh+vFomSGY65wOlutaky1BDt/03Dk+GyVIkAkP8Bu6Bx5OubYJ9DeurFga6d+kTvV N4saOi+GWJ/E1WZyux8lRv+zrQB5ddRt/2fgQqf2ccyXcKEe5Rmp6XFkgjR+cexSrFwZ gG1o2SCTobLdAzPrv0xFyZAGUNpm2dNsK8l+6WDX3ki6MoUtAKuVjuRFO1U/znZbHf1N IU6eS3Qnv9rN/+bcYr2b9GN1lZhYd7+/8jQO8PAqUVRQdSirTSk+eTG1iXpp7vIHZ4Dj 5lIc9F3IhFLhmSHBwN5Vae2STEVRCI9kbkcsGvwHh1eBP9xzSc9G4bFN8e4mYN5+rx3q RNgg== X-Gm-Message-State: ABUngvd/r89IbMIWX5DfonKthfXLgsaqxdii0r8ovIY4vKA+Vz2OtKcPT0wyncNPjoZY3Q== X-Received: by 10.99.114.15 with SMTP id n15mr16083034pgc.7.1478607300952; Tue, 08 Nov 2016 04:15:00 -0800 (PST) Received: from roar.ozlabs.ibm.com ([122.99.82.10]) by smtp.gmail.com with ESMTPSA id u127sm47846746pfu.21.2016.11.08.04.14.59 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 08 Nov 2016 04:15:00 -0800 (PST) From: Nicholas Piggin To: Michael Ellerman Subject: [PATCH 2/2] powerpc: fix second nested oops hang Date: Tue, 8 Nov 2016 23:14:45 +1100 Message-Id: <20161108121445.15303-3-npiggin@gmail.com> X-Mailer: git-send-email 2.10.2 In-Reply-To: <20161108121445.15303-1-npiggin@gmail.com> References: <20161108121445.15303-1-npiggin@gmail.com> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org, Nicholas Piggin Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" When ending an oops, don't clear die_owner unless the nest count went to zero. This prevents a second nested oops from hanging forever on the die_lock. Signed-off-by: Nicholas Piggin --- arch/powerpc/kernel/traps.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 26c3ba4..ba78e38 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -147,14 +147,15 @@ static void oops_end(unsigned long flags, struct pt_regs *regs, int signr) { bust_spinlocks(0); - die_owner = -1; add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); die_nest_count--; oops_exit(); printk("\n"); - if (!die_nest_count) + if (!die_nest_count) { /* Nest count reaches zero, release the lock. */ + die_owner = -1; arch_spin_unlock(&die_lock); + } raw_local_irq_restore(flags); crash_fadump(regs, "die oops");