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=-14.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 42FD3C43461 for ; Fri, 4 Sep 2020 13:19:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 147BB2078E for ; Fri, 4 Sep 2020 13:19:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="XffMdUMf"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="GToOOx1q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730358AbgIDNTe (ORCPT ); Fri, 4 Sep 2020 09:19:34 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:33090 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730369AbgIDNQR (ORCPT ); Fri, 4 Sep 2020 09:16:17 -0400 Date: Fri, 04 Sep 2020 13:16:10 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1599225371; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=fljRKHgAWHMbuzD4XnCCLGpYt5AlZ7Sxj0FjH8NVt6w=; b=XffMdUMfQRZ5jtuil1thZQ4Alg1h0bgV2AbMen5OVlY+9fo3g9vsE656m9pt5U7+ybACFy ODKWSqs5YDjI9aJh+rPFrqHBC2Jqgh+i0YLr/MlnT58yg0DqqkDYT+x7J7UpE7zCq8+Wqi QB6VOuyjUjncIMvVSkF5qFfDC4eGnRU0MMLRHbTBYT40EX1xD5uapWSBwHJwoM05Dzc14d cGmGIlRV+IRidNsDML8ZpOP6ikNR/yeVtBJGrXQ6oIHLzK5MqemI9AMQjt35ExOaRRURWj +XJlRuTTSLQTFrI96dQFfu9MHPz50zgkNpbQQtEuPvjpMIrPYu5RbtWAh9EJ2A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1599225371; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=fljRKHgAWHMbuzD4XnCCLGpYt5AlZ7Sxj0FjH8NVt6w=; b=GToOOx1q8b38nlxydhLx7/QiLDjfzseIvIb1ucRO77BMAX164ufIl3JYLLl+lcjrBRWgta FbObbnDMpHsVawDg== From: "tip-bot2 for Peter Zijlstra" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/entry] x86/debug: Sync BTF earlier Cc: "Peter Zijlstra (Intel)" , Thomas Gleixner , Daniel Thompson , Andy Lutomirski , x86 , LKML In-Reply-To: <20200902133200.786888252@infradead.org> References: <20200902133200.786888252@infradead.org> MIME-Version: 1.0 Message-ID: <159922537072.20229.12383477145708165237.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the x86/entry branch of tip: Commit-ID: c182487da1b5281463f2255d2347885dba219c08 Gitweb: https://git.kernel.org/tip/c182487da1b5281463f2255d2347885dba219c08 Author: Peter Zijlstra AuthorDate: Wed, 02 Sep 2020 15:25:52 +02:00 Committer: Thomas Gleixner CommitterDate: Fri, 04 Sep 2020 15:12:52 +02:00 x86/debug: Sync BTF earlier Move the BTF sync near the DR6 load, as this will be the only common code guaranteed to run on every #DB. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Tested-by: Daniel Thompson Acked-by: Andy Lutomirski Link: https://lore.kernel.org/r/20200902133200.786888252@infradead.org --- arch/x86/kernel/traps.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 81a2fb7..9945642 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -749,6 +749,13 @@ static __always_inline unsigned long debug_read_clear_dr6(void) /* Filter out all the reserved bits which are preset to 1 */ dr6 &= ~DR6_RESERVED; + /* + * The SDM says "The processor clears the BTF flag when it + * generates a debug exception." Clear TIF_BLOCKSTEP to keep + * TIF_BLOCKSTEP in sync with the hardware BTF flag. + */ + clear_thread_flag(TIF_BLOCKSTEP); + return dr6; } @@ -783,13 +790,6 @@ static void handle_debug(struct pt_regs *regs, unsigned long dr6, bool user) int si_code; /* - * The SDM says "The processor clears the BTF flag when it - * generates a debug exception." Clear TIF_BLOCKSTEP to keep - * TIF_BLOCKSTEP in sync with the hardware BTF flag. - */ - clear_thread_flag(TIF_BLOCKSTEP); - - /* * If DR6 is zero, no point in trying to handle it. The kernel is * not using INT1. */