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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 99EEFC433B4 for ; Mon, 17 May 2021 14:08:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7C3AF613C8 for ; Mon, 17 May 2021 14:08:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238032AbhEQOJb (ORCPT ); Mon, 17 May 2021 10:09:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:60286 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237987AbhEQOHC (ORCPT ); Mon, 17 May 2021 10:07:02 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8819561353; Mon, 17 May 2021 14:05:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621260346; bh=IPfpyrXS7tHH5SJRrW7b2YGSvcyyhg5Wvzg96PJhElQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=R29L9mKsAm0LeyvwnUcuPdsUnlqdl0KqB4TA8JBs9W/VVPS+iLN5F8diWK1fyiy+X elGEktGYXf5spKSjcR1Dc+m+BBdUExidFnGBnvH4Qo/LFx2wrEk8vBYyuB0oexuJZA LgIm/jyT23jEJUl2zK6YMfU2437WT0kNmKS1spUk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Christophe Leroy , Michael Ellerman , Sasha Levin Subject: [PATCH 5.12 040/363] powerpc/32: Statically initialise first emergency context Date: Mon, 17 May 2021 15:58:26 +0200 Message-Id: <20210517140303.958582084@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210517140302.508966430@linuxfoundation.org> References: <20210517140302.508966430@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Christophe Leroy [ Upstream commit a4719f5bb6d7dc220bffdc1b9f5ce5eaa5543581 ] The check of the emergency context initialisation in vmap_stack_overflow is buggy for the SMP case, as it compares r1 with 0 while in the SMP case r1 is offseted by the CPU id. Instead of fixing it, just perform static initialisation of the first emergency context. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/4a67ba422be75713286dca0c86ee0d3df2eb6dfa.1615552867.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin --- arch/powerpc/kernel/head_32.h | 6 +----- arch/powerpc/kernel/setup_32.c | 2 +- 2 files changed, 2 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h index 5d4706c14572..cf8ca08295bf 100644 --- a/arch/powerpc/kernel/head_32.h +++ b/arch/powerpc/kernel/head_32.h @@ -261,11 +261,7 @@ label: lis r1, emergency_ctx@ha #endif lwz r1, emergency_ctx@l(r1) - cmpwi cr1, r1, 0 - bne cr1, 1f - lis r1, init_thread_union@ha - addi r1, r1, init_thread_union@l -1: addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE + addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE EXCEPTION_PROLOG_2 SAVE_NVGPRS(r11) addi r3, r1, STACK_FRAME_OVERHEAD diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c index 8ba49a6bf515..d7c1f92152af 100644 --- a/arch/powerpc/kernel/setup_32.c +++ b/arch/powerpc/kernel/setup_32.c @@ -164,7 +164,7 @@ void __init irqstack_early_init(void) } #ifdef CONFIG_VMAP_STACK -void *emergency_ctx[NR_CPUS] __ro_after_init; +void *emergency_ctx[NR_CPUS] __ro_after_init = {[0] = &init_stack}; void __init emergency_stack_init(void) { -- 2.30.2