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=-8.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham 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 3D521C4321A for ; Sat, 29 Jun 2019 11:39:33 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E665F214AF for ; Sat, 29 Jun 2019 11:39:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E665F214AF Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 45bWrL63z6zDqx4 for ; Sat, 29 Jun 2019 21:39:30 +1000 (AEST) Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 45bWpV2V51zDqQR for ; Sat, 29 Jun 2019 21:37:54 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Received: by ozlabs.org (Postfix, from userid 1034) id 45bWpV1jWCz9s5c; Sat, 29 Jun 2019 21:37:54 +1000 (AEST) X-powerpc-patch-notification: thanks X-powerpc-patch-commit: e13e7cd4c0c1cc9984d9b6a8663e10d76b53f2aa X-Patchwork-Hint: ignore In-Reply-To: <20190621225554.1913-1-npiggin@gmail.com> To: Nicholas Piggin , linuxppc-dev@lists.ozlabs.org From: Michael Ellerman Subject: Re: [PATCH] powerpc/64s/exception: Fix machine check early corrupting AMR Message-Id: <45bWpV1jWCz9s5c@ozlabs.org> Date: Sat, 29 Jun 2019 21:37:54 +1000 (AEST) 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: Nicholas Piggin Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Fri, 2019-06-21 at 22:55:54 UTC, Nicholas Piggin wrote: > The early machine check runs in real mode, so locking is unnecessary. > Worse, the windup does not restore AMR, so this can result in a false > KUAP fault after a recoverable machine check hits inside a user copy > operation. > > Fix this similarly to HMI by just avoiding the kuap lock in the > early machine check handler (it will be set by the late handler that > runs in virtual mode if that runs). If the virtual mode handler is > reached, it will lock and restore the AMR. > > Fixes: 890274c2dc4c0 ("powerpc/64s: Implement KUAP for Radix MMU") > Cc: Russell Currey > Signed-off-by: Nicholas Piggin Applied to powerpc fixes, thanks. https://git.kernel.org/powerpc/c/e13e7cd4c0c1cc9984d9b6a8663e10d76b53f2aa cheers