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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 A1188C63697 for ; Tue, 17 Nov 2020 15:17:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 487BD24198 for ; Tue, 17 Nov 2020 15:17:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="B0dX1Z6B" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733165AbgKQPRA (ORCPT ); Tue, 17 Nov 2020 10:17:00 -0500 Received: from mail.kernel.org ([198.145.29.99]:34368 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729184AbgKQPQ6 (ORCPT ); Tue, 17 Nov 2020 10:16:58 -0500 Received: from localhost.localdomain (unknown [176.167.180.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A6C1324198; Tue, 17 Nov 2020 15:16:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605626218; bh=F/3unrXBIqFN1AMtFeEOTOxOuveYqZ1JM6MxSNhHAkw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B0dX1Z6Bg3R7AZDLS5f4f6Gt07rcRZBx64QBrcoydbb0bryEAcLUDPb72xfUm0f3A QMTRHRY0wSEXZt6VVk9+/razvK2g2VL4d+KIrTDG9k+DlGjSWhrL11dtRiww/y7DJb ARhhYaqXLOAl8R2+CNaT08gi9bHccpxt9/RnsC8Y= From: Frederic Weisbecker To: Peter Zijlstra Cc: LKML , Frederic Weisbecker , "Paul E . McKenney" , Thomas Gleixner , Phil Auld , Marcelo Tosatti Subject: [PATCH 5/5] x86: Support HAVE_CONTEXT_TRACKING_OFFSTACK Date: Tue, 17 Nov 2020 16:16:37 +0100 Message-Id: <20201117151637.259084-6-frederic@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201117151637.259084-1-frederic@kernel.org> References: <20201117151637.259084-1-frederic@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org A lot of ground work has been performed on x86 entry code. Fragile path between user_enter() and user_exit() have IRQs disabled. Uses of RCU and intrumentation in these fragile areas have been explicitly annotated and protected. This architecture doesn't need exception_enter()/exception_exit() anymore and has therefore earned CONFIG_HAVE_CONTEXT_TRACKING_OFFSTACK. Signed-off-by: Frederic Weisbecker Cc: Marcelo Tosatti Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Phil Auld Cc: Thomas Gleixner --- arch/x86/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index f6946b81f74a..d793361839b5 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -162,6 +162,7 @@ config X86 select HAVE_CMPXCHG_DOUBLE select HAVE_CMPXCHG_LOCAL select HAVE_CONTEXT_TRACKING if X86_64 + select HAVE_CONTEXT_TRACKING_OFFSTACK if HAVE_CONTEXT_TRACKING select HAVE_C_RECORDMCOUNT select HAVE_DEBUG_KMEMLEAK select HAVE_DMA_CONTIGUOUS -- 2.25.1