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 X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8FDC1C43603 for ; Wed, 11 Dec 2019 15:58:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 635192073D for ; Wed, 11 Dec 2019 15:58:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576079937; bh=U2C69MNLaSO6Y0NTKcM6QCvHTZjD6tMLoLQs47BJnaU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=NbyJiuELj4sMWjKwd05yJgHlY3FFyoFRJzq7jXwbg4TmIg/XmUoCTXvQSj4+HMuyC sogUI+j/GjarDkjJfemQPTZQIV3MaFwfRv0AEu2cytFavZSwMLhlwhRnVUm/3dsNB1 nhYGG5AmmsRKDrS+ewWyo2uNjo2cPEqGffuQxkek= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730287AbfLKP6x (ORCPT ); Wed, 11 Dec 2019 10:58:53 -0500 Received: from mail.kernel.org ([198.145.29.99]:39130 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731602AbfLKPOO (ORCPT ); Wed, 11 Dec 2019 10:14:14 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 288032467A; Wed, 11 Dec 2019 15:14:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576077253; bh=U2C69MNLaSO6Y0NTKcM6QCvHTZjD6tMLoLQs47BJnaU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eZ5bRElAQ6JsBbMvVmYfpWBL0DG67DE9/xkVo9ZiMfbskIpX37iyfEYe/fbtlbtWA eaW7Umiq8Fi9kWCaIEZBVS02/7iH+DDXkNqW2FFB+jOPTN7WZomSTbdebTcSjJbVvF qrDLh5mL23Wl/gMQBm5g+G+PwfRZzPnB2ANkHr+8= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Vasily Gorbik , Heiko Carstens , Sasha Levin , linux-s390@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 130/134] s390: disable preemption when switching to nodat stack with CALL_ON_STACK Date: Wed, 11 Dec 2019 10:11:46 -0500 Message-Id: <20191211151150.19073-130-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191211151150.19073-1-sashal@kernel.org> References: <20191211151150.19073-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vasily Gorbik [ Upstream commit 7f28dad395243c5026d649136823bbc40029a828 ] Make sure preemption is disabled when temporary switching to nodat stack with CALL_ON_STACK helper, because nodat stack is per cpu. Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin --- arch/s390/kernel/machine_kexec.c | 2 ++ arch/s390/mm/maccess.c | 12 +++++++++--- 2 files changed, 11 insertions(+), 3 deletions(-) diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c index 444a19125a815..dcaadceaf6efc 100644 --- a/arch/s390/kernel/machine_kexec.c +++ b/arch/s390/kernel/machine_kexec.c @@ -164,7 +164,9 @@ static bool kdump_csum_valid(struct kimage *image) #ifdef CONFIG_CRASH_DUMP int rc; + preempt_disable(); rc = CALL_ON_STACK(do_start_kdump, S390_lowcore.nodat_stack, 1, image); + preempt_enable(); return rc == 0; #else return false; diff --git a/arch/s390/mm/maccess.c b/arch/s390/mm/maccess.c index 1864a8bb9622f..88d5fcf67a2f1 100644 --- a/arch/s390/mm/maccess.c +++ b/arch/s390/mm/maccess.c @@ -115,9 +115,15 @@ static unsigned long _memcpy_real(unsigned long dest, unsigned long src, */ int memcpy_real(void *dest, void *src, size_t count) { - if (S390_lowcore.nodat_stack != 0) - return CALL_ON_STACK(_memcpy_real, S390_lowcore.nodat_stack, - 3, dest, src, count); + int rc; + + if (S390_lowcore.nodat_stack != 0) { + preempt_disable(); + rc = CALL_ON_STACK(_memcpy_real, S390_lowcore.nodat_stack, 3, + dest, src, count); + preempt_enable(); + return rc; + } /* * This is a really early memcpy_real call, the stacks are * not set up yet. Just call _memcpy_real on the early boot -- 2.20.1