From patchwork Wed Apr 27 22:49:21 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Guilherme G. Piccoli" X-Patchwork-Id: 1623378 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=igalia.com header.i=@igalia.com header.a=rsa-sha256 header.s=20170329 header.b=PMFgjQG4; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org (client-ip=112.213.38.117; helo=lists.ozlabs.org; envelope-from=linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org; receiver=) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by bilbo.ozlabs.org (Postfix) with ESMTPS id 4Kpdl5100Jz9s2R for ; Thu, 28 Apr 2022 11:46:41 +1000 (AEST) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4Kpdl500W8z3fTG for ; Thu, 28 Apr 2022 11:46:40 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=igalia.com header.i=@igalia.com header.a=rsa-sha256 header.s=20170329 header.b=PMFgjQG4; dkim-atps=neutral X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=igalia.com (client-ip=178.60.130.6; helo=fanzine2.igalia.com; envelope-from=gpiccoli@igalia.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=igalia.com header.i=@igalia.com header.a=rsa-sha256 header.s=20170329 header.b=PMFgjQG4; dkim-atps=neutral Received: from fanzine2.igalia.com (fanzine.igalia.com [178.60.130.6]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4KpZ0K14G4z3bYF for ; Thu, 28 Apr 2022 08:57:53 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=C9iT/xJ8gF8J/f7SmqQO2c8pu+KvBPlFfkqGdYboS2I=; b=PMFgjQG40D4y0EE10+nqxAPHVI yNLZ1EZJdP0IH30iYafdBfM788VaINOAVfe8Gnevld0DclzQJRd8t+br/vJapdawGOEWHQTLdmHei 1IQvYGZ//MLpN+QQDVtOXWSfDQyyspNE1J3gOgOC4NUam3dGx8JeBgJ9jpYRHFoaP71Y3fG1ERN+7 JvwIb059Xf3lNBTrEP8JiyuPOh5ugwSvNao5NfaR+bMPV8BospKPkEU02jshVAtp1UBbOdjrRb2r2 ze90RIwfaZigyOQntmQCmXs163wt4gsMUWHmf1nSoidLeEjFKj9WA7H531Eyz4iqvzof4LvLiIP9u dq8Lxg9g==; Received: from [179.113.53.197] (helo=localhost) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1njqbL-0002UI-QD; Thu, 28 Apr 2022 00:57:40 +0200 From: "Guilherme G. Piccoli" To: akpm@linux-foundation.org, bhe@redhat.com, pmladek@suse.com, kexec@lists.infradead.org Subject: [PATCH 27/30] powerpc: Do not force all panic notifiers to execute before kdump Date: Wed, 27 Apr 2022 19:49:21 -0300 Message-Id: <20220427224924.592546-28-gpiccoli@igalia.com> X-Mailer: git-send-email 2.36.0 In-Reply-To: <20220427224924.592546-1-gpiccoli@igalia.com> References: <20220427224924.592546-1-gpiccoli@igalia.com> MIME-Version: 1.0 X-Mailman-Approved-At: Thu, 28 Apr 2022 11:34:03 +1000 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-hyperv@vger.kernel.org, halves@canonical.com, gregkh@linuxfoundation.org, peterz@infradead.org, alejandro.j.jimenez@oracle.com, linux-remoteproc@vger.kernel.org, feng.tang@intel.com, linux-mips@vger.kernel.org, hidehiro.kawai.ez@hitachi.com, Paul Mackerras , sparclinux@vger.kernel.org, will@kernel.org, tglx@linutronix.de, linux-leds@vger.kernel.org, linux-s390@vger.kernel.org, mikelley@microsoft.com, john.ogness@linutronix.de, corbet@lwn.net, paulmck@kernel.org, fabiomirmar@gmail.com, x86@kernel.org, mingo@redhat.com, bcm-kernel-feedback-list@broadcom.com, Hari Bathini , xen-devel@lists.xenproject.org, dyoung@redhat.com, vgoyal@redhat.com, linux-xtensa@linux-xtensa.org, dave.hansen@linux.intel.com, keescook@chromium.org, arnd@arndb.de, linux-pm@vger.kernel.org, coresight@lists.linaro.org, linux-um@lists.infradead.org, rostedt@goodmis.org, rcu@vger.kernel.org, bp@alien8.de, Nicholas Piggin , luto@kernel.org, linux-tegra@vger.kernel.org, openipmi-developer@lists.sourceforge.net, andriy.shevchenko@linux.intel.com, senozhatsky@chromium.org, linux-arm-kernel@lists.infradead.org, linux-edac@vger.kernel.org, jgross@suse.com, linux-parisc@vger.kernel.org, netdev@vger.kernel.org, kernel@gpiccoli.net, linux-kernel@vger.kernel.org, stern@rowland.harvard.edu, gpiccoli@igalia.com, d.hatayama@jp.fujitsu.com, mhiramat@kernel.org, kernel-dev@igalia.com, linux-alpha@vger.kernel.org, vkuznets@redhat.com, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Commit 06e629c25daa ("powerpc/fadump: Fix inaccurate CPU state info in vmcore generated with panic") introduced a hardcoded setting of kernel parameter "crash_kexec_post_notifiers", effectively forcing all the panic notifiers to execute earlier in the panic path, before kdump. The reason for that was a fadump issue on collecting data accurately, due to smp_send_stop() setting all CPUs offline, so the net effect desired with this change was to avoid calling the regular CPU shutdown function, and instead rely on crash_smp_send_stop(), which copes fine with fadump. The collateral effect was to increase the risk for kdump if fadump is not used, since it forces all panic notifiers to execute early, before kdump. Happens that, after a panic refactor, crash_smp_send_stop() is now used by default in the panic path, so there is no reason to mess with the notifiers ordering (which was also improved in the refactor) from within arch code. Fixes: 06e629c25daa ("powerpc/fadump: Fix inaccurate CPU state info in vmcore generated with panic") Cc: Benjamin Herrenschmidt Cc: Hari Bathini Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Paul Mackerras Signed-off-by: Guilherme G. Piccoli --- We'd like to thanks specially the MiniCloud infrastructure [0] maintainers, that allow us to test PowerPC code in a very complete, functional and FREE environment. [0] https://openpower.ic.unicamp.br/minicloud arch/powerpc/kernel/fadump.c | 8 -------- 1 file changed, 8 deletions(-) diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c index 65562c4a0a69..35ae8c09af66 100644 --- a/arch/powerpc/kernel/fadump.c +++ b/arch/powerpc/kernel/fadump.c @@ -1649,14 +1649,6 @@ int __init setup_fadump(void) register_fadump(); } - /* - * In case of panic, fadump is triggered via ppc_panic_event() - * panic notifier. Setting crash_kexec_post_notifiers to 'true' - * lets panic() function take crash friendly path before panic - * notifiers are invoked. - */ - crash_kexec_post_notifiers = true; - return 1; } /*