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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 5B33CC4708F for ; Wed, 2 Jun 2021 18:42:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4070F61359 for ; Wed, 2 Jun 2021 18:42:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229586AbhFBSoj (ORCPT ); Wed, 2 Jun 2021 14:44:39 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:48390 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229541AbhFBSoi (ORCPT ); Wed, 2 Jun 2021 14:44:38 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out03.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1loVpL-00G6Zj-Ds; Wed, 02 Jun 2021 12:42:51 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=email.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1loVpG-00Dbdm-VU; Wed, 02 Jun 2021 12:42:51 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Jiashuo Liang Cc: Dave Hansen , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" , linux-kernel@vger.kernel.org In-Reply-To: <20210601085203.40214-1-liangjs@pku.edu.cn> (Jiashuo Liang's message of "Tue, 1 Jun 2021 16:52:03 +0800") References: <20210601085203.40214-1-liangjs@pku.edu.cn> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) Date: Wed, 02 Jun 2021 13:42:22 -0500 Message-ID: <87wnrcqfap.fsf@disp2133> MIME-Version: 1.0 Content-Type: text/plain X-XM-SPF: eid=1loVpG-00Dbdm-VU;;;mid=<87wnrcqfap.fsf@disp2133>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1/RFpTRdnELpHk43fPsNaIe6o6GVXXfTp0= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: Re: [PATCH] signal/x86: Don't send SIGSEGV twice on SEGV_PKUERR X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jiashuo Liang writes: > Before this patch, the __bad_area_nosemaphore function calls both > force_sig_pkuerr and force_sig_fault when handling SEGV_PKUERR. This does > not cause problems because the second signal is filtered by the > legacy_queue check in __send_signal. But it causes the kernel to do > unnecessary work. > > This patch should fix it. Have you been able to test this patch? Acked-by: "Eric W. Biederman" Does one of the x86 maintainers want to pick up this trivial fix or should I pick it up? Eric > Fixes: 9db812dbb29d ("signal/x86: Call force_sig_pkuerr from __bad_area_nosemaphore") > Suggested-by: "Eric W. Biederman" > Signed-off-by: Jiashuo Liang > --- > arch/x86/mm/fault.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c > index 1c548ad00752..6bda7f67d737 100644 > --- a/arch/x86/mm/fault.c > +++ b/arch/x86/mm/fault.c > @@ -836,8 +836,8 @@ __bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code, > > if (si_code == SEGV_PKUERR) > force_sig_pkuerr((void __user *)address, pkey); > - > - force_sig_fault(SIGSEGV, si_code, (void __user *)address); > + else > + force_sig_fault(SIGSEGV, si_code, (void __user *)address); > > local_irq_disable(); > }