From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BBEB1C4167B for ; Tue, 18 Jan 2022 03:02:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352318AbiARC7o (ORCPT ); Mon, 17 Jan 2022 21:59:44 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:54926 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344041AbiARCr6 (ORCPT ); Mon, 17 Jan 2022 21:47:58 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 64FD8B81132; Tue, 18 Jan 2022 02:47:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 47BC9C36AE3; Tue, 18 Jan 2022 02:47:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1642474076; bh=vPTjVddl5DKb6MbfQQ7t/DzPJ0dMH0IYt5/qolz2wgk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dekRbk3Mf5uMW6ECm/SHkeqhApRgYginnD9bvSv2hFeVSqAGKRI+8TCUMeSJB3rKb wOvrQcLfVIJsa3kirnI9Cnn/9IHLqWWKUzoFflnsX5sSbvbfdYUjf6rj4lUNlu6r3q hFbA4eOzGYdIjYIGwYiTPIcbiRRFf7i1Z9oVrpBy4M2Vsbd7IGLKsWybyTcWDv8Mb/ ybEOmhVVGsMDLXtOgiVzT3U3QY/cqUZTVDXf1SCeEMZYzs//np8IudVDpgFm080lYY Ufsp6Oeyr9gBTuzeMb1KPLdvvC5QMH05CD17Np6PfHdzmVlXfKz+UqTgehYhd85Quf MEDv1KuEX9IVQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Borislav Petkov , Sasha Levin , tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org Subject: [PATCH AUTOSEL 4.19 24/59] x86/mce: Mark mce_panic() noinstr Date: Mon, 17 Jan 2022 21:46:25 -0500 Message-Id: <20220118024701.1952911-24-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220118024701.1952911-1-sashal@kernel.org> References: <20220118024701.1952911-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Borislav Petkov [ Upstream commit 3c7ce80a818fa7950be123cac80cd078e5ac1013 ] And allow instrumentation inside it because it does calls to other facilities which will not be tagged noinstr. Fixes vmlinux.o: warning: objtool: do_machine_check()+0xc73: call to mce_panic() leaves .noinstr.text section Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/r/20211208111343.8130-8-bp@alien8.de Signed-off-by: Sasha Levin --- arch/x86/kernel/cpu/mcheck/mce.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index 2a13468f87739..56c4456434a82 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -295,11 +295,17 @@ static void wait_for_panic(void) panic("Panicing machine check CPU died"); } -static void mce_panic(const char *msg, struct mce *final, char *exp) +static noinstr void mce_panic(const char *msg, struct mce *final, char *exp) { - int apei_err = 0; struct llist_node *pending; struct mce_evt_llist *l; + int apei_err = 0; + + /* + * Allow instrumentation around external facilities usage. Not that it + * matters a whole lot since the machine is going to panic anyway. + */ + instrumentation_begin(); if (!fake_panic) { /* @@ -314,7 +320,7 @@ static void mce_panic(const char *msg, struct mce *final, char *exp) } else { /* Don't log too much for fake panic */ if (atomic_inc_return(&mce_fake_panicked) > 1) - return; + goto out; } pending = mce_gen_pool_prepare_records(); /* First print corrected ones that are still unlogged */ @@ -352,6 +358,9 @@ static void mce_panic(const char *msg, struct mce *final, char *exp) panic(msg); } else pr_emerg(HW_ERR "Fake kernel panic: %s\n", msg); + +out: + instrumentation_end(); } /* Support code for software error injection */ -- 2.34.1