From patchwork Fri Feb 17 22:22:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josh Poimboeuf X-Patchwork-Id: 58785 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:adf:eb09:0:0:0:0:0 with SMTP id s9csp99289wrn; Fri, 17 Feb 2023 14:30:51 -0800 (PST) X-Google-Smtp-Source: AK7set96eg52BOf2lqe2/ry2vJmOxA8t0EqjFoVqu+dgaWF7X/I0Zb6SkUFVQ4ny4tsiyB4raTwe X-Received: by 2002:a17:906:4910:b0:8b1:7de0:c854 with SMTP id b16-20020a170906491000b008b17de0c854mr4703022ejq.41.1676673051422; Fri, 17 Feb 2023 14:30:51 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1676673051; cv=none; d=google.com; s=arc-20160816; b=JNZ2Zl70CWUIRIGHJ/h1ZJGTEeHmuKlu2VdJZBA+/UL20yAV9lOHa0sK1h2RxvQCew gj2xP4ucwc2CU9Lb8posUUBkS5TxEMb3H9LFFLAE2pZERtM5N8qYd7J31zdFmwJFL1t1 1evut0nCUEWZ6ON+QNibG1oiHEQflbfQgmkZv1p9KQV9k6CDZwIQtCuPNwgsNy4fkQzE /bPu0oeVqcSlDQ1tNPqhO8EVQvTxtuUSycveX3uCr3qjPHkFSYdEDW8IcvoevLOTxyHW 1r6B3wm+wUKT/NRysZUSRGA/hHc5raIEFShJZvsC1pqtuJ/PVOCXL7HipTj+DZo9iKTQ veKg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=4jU+SGCwX400pg3X4OgbqE9w71eYcYGFHVV8AI/hOxc=; b=sH3ncamc5t7EQ+FJeqGlBveRtb8rlth+GruFBETRkxbuH28AT5rSRdGxGT7qL5sN+x atu4e8sJuaIOiGOd+DyMw94YawAuLGN7Abq2Xwsp/NN5EtcmzVSczCdfiObXIvUqacCv +Eg1ISt+eHFKsHdkzMUt4rlLYcnU6RiKJ33uWFb9smV5sAFL8l4tWesSvf45R4rmQcyD 6ILdXBNhwHx0+MRDV9AfEux8Sik7ToDEq9G9R5BPoA48WlATGThteRTyndx7Y0OvqkoD C2Ujwb5XI4M6Uv8Q1HgmNYc8o6is7p5FVMyMkzxtFrRVHTOuwX0mPXRqfO3LGNHfoV31 hvHQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=HvaqSr5P; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id vl10-20020a17090730ca00b008b1484584dfsi6124488ejb.4.2023.02.17.14.30.28; Fri, 17 Feb 2023 14:30:51 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=HvaqSr5P; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229848AbjBQWXG (ORCPT + 99 others); Fri, 17 Feb 2023 17:23:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229509AbjBQWXC (ORCPT ); Fri, 17 Feb 2023 17:23:02 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B80345D3EB; Fri, 17 Feb 2023 14:23:01 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 6EF30B82DD0; Fri, 17 Feb 2023 22:23:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BC44DC433EF; Fri, 17 Feb 2023 22:22:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1676672579; bh=nDYIubJTBPWH5ktJId6VhvPlAhhjbmackYfSKNUBnA8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HvaqSr5PbTHNs8mAMaAmaYbTfmj4JGX1vO3kz55UvEw93l5BToEp5+PskKaCtMUeS OUMKsxV+tVXyKFXE+8+csdac7DIDBeylDt7DWhvsWVljlU4UlctSUoRrOmFMPlYBpv zgOZhnks24H2u7Ie0dgDdmYZftBRMVkj0epeKHM4sLSs17K8xg3btcsVxQ2K3C5h7u sva5ly/+lj6K1pMbn2gwTWJBSx0JCIp/u7aSiSH3zae9c7968ZiY97Coz7SedTHhNz q31EckXsm5CLqqo9HEQ7WAcVB4TnJPv7Wpy4g6/QRkUk09ZQ7s5cUGDjCVS1gHXIfJ Lmn9k+xGyVk3Q== From: Josh Poimboeuf To: live-patching@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Seth Forshee , Peter Zijlstra , Song Liu , Mark Rutland , Petr Mladek , Joe Lawrence , Miroslav Benes , Jiri Kosina , Ingo Molnar , Rik van Riel Subject: [PATCH v2 1/3] livepatch: Skip task_call_func() for current task Date: Fri, 17 Feb 2023 14:22:54 -0800 Message-Id: <4b92e793462d532a05f03767151fa29db3e68e13.1676672328.git.jpoimboe@kernel.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: References: MIME-Version: 1.0 Content-type: text/plain X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1758119121778812375?= X-GMAIL-MSGID: =?utf-8?q?1758119121778812375?= The current task doesn't need the scheduler's protection to unwind its own stack. Tested-by: Seth Forshee (DigitalOcean) Reviewed-by: Petr Mladek Signed-off-by: Josh Poimboeuf --- kernel/livepatch/transition.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c index f1b25ec581e0..4d1f443778f7 100644 --- a/kernel/livepatch/transition.c +++ b/kernel/livepatch/transition.c @@ -307,7 +307,11 @@ static bool klp_try_switch_task(struct task_struct *task) * functions. If all goes well, switch the task to the target patch * state. */ - ret = task_call_func(task, klp_check_and_switch_task, &old_name); + if (task == current) + ret = klp_check_and_switch_task(current, &old_name); + else + ret = task_call_func(task, klp_check_and_switch_task, &old_name); + switch (ret) { case 0: /* success */ break;