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=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 04152C433E2 for ; Mon, 20 Jul 2020 16:14:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D2DBC207DD for ; Mon, 20 Jul 2020 16:14:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595261675; bh=B3Bb4Lnno2qpjP9vt8hrDEQ574TUdIAISvH8Q5nSA0M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=IJ247VBwFqv9KMujmhDlMNX6SuDLhl3+tL2AxbUKcOB8gNKRv7uqkPPNnLrbcojvB hTZc5W4eMixXpcM4j5hJnjrYmNn1bhF/gk++PGDpjz3PqaHqwqUxKS0SfLWfb8hJnc 9LMfkkwuKsm50p5S7dRUOkh0JmI70SE0UbXujZTU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388292AbgGTQOe (ORCPT ); Mon, 20 Jul 2020 12:14:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:55050 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388278AbgGTQOc (ORCPT ); Mon, 20 Jul 2020 12:14:32 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B98B5207DD; Mon, 20 Jul 2020 16:14:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595261672; bh=B3Bb4Lnno2qpjP9vt8hrDEQ574TUdIAISvH8Q5nSA0M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2Ken8zqCVGm7mI1taZdBDFEaGvoIlLxFiMLLxI1orSZ2KLTSpZohBhO9UIXTzPERq 0mHZj29t1st1/S+VniBGzMl9fnZg2yyyX9/9cMgS9wU+WLSw3eUPzovlBtvhewhlt2 32Et4Z5PrOoJ6/1ZdupBUKAJ48fV8o6Q9CsncnW4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Satheesh Rajendran , Laurent Dufour , Thiago Jung Bauermann , Michael Ellerman Subject: [PATCH 5.7 200/244] powerpc/pseries/svm: Fix incorrect check for shared_lppaca_size Date: Mon, 20 Jul 2020 17:37:51 +0200 Message-Id: <20200720152835.360523689@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200720152825.863040590@linuxfoundation.org> References: <20200720152825.863040590@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Satheesh Rajendran commit b710d27bf72068b15b2f0305d825988183e2ff28 upstream. Early secure guest boot hits the below crash while booting with vcpus numbers aligned with page boundary for PAGE size of 64k and LPPACA size of 1k i.e 64, 128 etc. Partition configured for 64 cpus. CPU maps initialized for 1 thread per core ------------[ cut here ]------------ kernel BUG at arch/powerpc/kernel/paca.c:89! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries This is due to the BUG_ON() for shared_lppaca_total_size equal to shared_lppaca_size. Instead the code should only BUG_ON() if we have exceeded the total_size, which indicates we've overflowed the array. Fixes: bd104e6db6f0 ("powerpc/pseries/svm: Use shared memory for LPPACA structures") Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Satheesh Rajendran Reviewed-by: Laurent Dufour Reviewed-by: Thiago Jung Bauermann [mpe: Reword change log to clarify we're fixing not removing the check] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200619070113.16696-1-sathnaga@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/paca.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/powerpc/kernel/paca.c +++ b/arch/powerpc/kernel/paca.c @@ -86,7 +86,7 @@ static void *__init alloc_shared_lppaca( * This is very early in boot, so no harm done if the kernel crashes at * this point. */ - BUG_ON(shared_lppaca_size >= shared_lppaca_total_size); + BUG_ON(shared_lppaca_size > shared_lppaca_total_size); return ptr; }