From patchwork Tue Nov 8 12:14:44 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicholas Piggin X-Patchwork-Id: 692279 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [103.22.144.68]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3tCpHF1XJdz9tlB for ; Tue, 8 Nov 2016 23:18:01 +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="fYQ838gJ"; 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 3tCpHF083WzDvbn for ; Tue, 8 Nov 2016 23:18:01 +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="fYQ838gJ"; 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 3tCpCl5MYxzDvPF for ; Tue, 8 Nov 2016 23:14:59 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="fYQ838gJ"; dkim-atps=neutral Received: by mail-pf0-x244.google.com with SMTP id i88so19280186pfk.2 for ; Tue, 08 Nov 2016 04:14:59 -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=IjSaFNkYHVSz5D9xnoGviDb/BOPIpVTU++++5KIwi60=; b=fYQ838gJvS6T82rfBSbgpT9Ncwd7dyTLixSuxgp+/sYuFSj2Cdpgsh2xdRw58PJcxP NQJENUcNT2Dx4eEJaF86mNNH33xjF874UahKHIRwaOEMuL8GDB3RQv2QTdDBty8oVpqC 9Gk0T5un5wBMM6mfGlKrhUdaygdE6l+BSlzSmhEbVre+AW0h14DwcGvT4+m8P896Vwdc s0NPTpI8eq50YIyb18TBEIk/dSwH2aDENAbvuZ63o6pb96ts5CzRDFe5yP12AcNAFjau MNC8vyGm36PpJxtQntCASMLlmNVXfzflnqdTp0Ir3kp6734rab1V4VaJiktXe07jOgo3 vWwA== 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=IjSaFNkYHVSz5D9xnoGviDb/BOPIpVTU++++5KIwi60=; b=ESQKYxn/3bdV2S8cL4KeY+jf1KwJAzS3BdKo301zhC+CzPKJPMBWTXrgJEEUqOFkfs TvN8HssgSWObZFTh7+tVBMzCYn+E9c6MG+t9fNQuG202zBgnWC7DhjMBp8vaNy7LwWC9 zxoxeIRy2wdBO9bEOIg7npPeXnBj8Orm3e0DUGYMELxHtHbEYwjqjZS4GXBo+Xwf6M/w jACiKM11nOH7xwmsmi/ofuBjzWDi8DFUa38NsxjOo7owEx0w6K9uvKYgQIciNYc/cp0U 1E/SGFxE68zj5jgJMog5aJP92ZA0157q9PRduo03C4wVS139B7CmrKE+yKXLva/efkDv ojWA== X-Gm-Message-State: ABUngveA0Xa3d8IbYhZ3HlRSA4McReZaHSWXNQQ4Z9xb3X3eoZ6onP0xK9NYaybLOl/GWQ== X-Received: by 10.99.226.83 with SMTP id y19mr18440461pgj.147.1478607298145; Tue, 08 Nov 2016 04:14:58 -0800 (PST) Received: from roar.ozlabs.ibm.com ([122.99.82.10]) by smtp.gmail.com with ESMTPSA id u127sm47846746pfu.21.2016.11.08.04.14.56 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 08 Nov 2016 04:14:57 -0800 (PST) From: Nicholas Piggin To: Michael Ellerman Subject: [PATCH 1/2] powerpc: fix graceful debugger recovery Date: Tue, 8 Nov 2016 23:14:44 +1100 Message-Id: <20161108121445.15303-2-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 exiting xmon with 'x' (exit and recover), oops_begin bails out immediately, but die then calls __die() and oops_end(), which cause a lot of bad things to happen. If the debugger was attached then went to graceful recovery, exit from die() immediately. Signed-off-by: Nicholas Piggin --- arch/powerpc/kernel/traps.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 7480902..26c3ba4 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -122,9 +122,6 @@ static unsigned long oops_begin(struct pt_regs *regs) int cpu; unsigned long flags; - if (debugger(regs)) - return 1; - oops_enter(); /* racy, but better than risking deadlock. */ @@ -227,8 +224,12 @@ NOKPROBE_SYMBOL(__die); void die(const char *str, struct pt_regs *regs, long err) { - unsigned long flags = oops_begin(regs); + unsigned long flags; + + if (debugger(regs)) + return; + flags = oops_begin(regs); if (__die(str, regs, err)) err = 0; oops_end(flags, regs, err);