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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D5DA7C4321E for ; Tue, 22 Nov 2022 20:39:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234880AbiKVUjy (ORCPT ); Tue, 22 Nov 2022 15:39:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45840 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233928AbiKVUju (ORCPT ); Tue, 22 Nov 2022 15:39:50 -0500 Received: from smtpout.efficios.com (smtpout.efficios.com [167.114.26.122]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 546DE716E3; Tue, 22 Nov 2022 12:39:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=efficios.com; s=smtpout1; t=1669149584; bh=ow2wHboTcwRtSOUGXRGJ9ltX+L8eM9I6Nfqms25JGf4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KzuJsJ+A54gpO+PRhoOUBboRSMMY965HVnq4OsxK2ZSH3HZusxjhQKnlhyKG16O6u N7/OlbG9xcJxngNN+hWkRaxKOt1TaN1wAk0jpTwztZpAI38yGfb3rBXo4QSOzlnGMR NK2brKziL4hZHD89/pc9swAvvdL5oDuuT8oY8k7ZyiD1HNqCi3VKfDVIibSM8vmKJk tD9knFgwE8z8RlLSOmUnkAHHv79ZjgV5OL462dHNdgSXm7Ois+Di29YGIpOJ2Jjbp8 3aa5jysMcKJ1VP93M0e8kuJ8a30vephtFwoXQ8thLaKWpp2eRFDDHb9K3TpLurkvut 3OSTDuq9ule5g== Received: from localhost.localdomain (192-222-180-24.qc.cable.ebox.net [192.222.180.24]) by smtpout.efficios.com (Postfix) with ESMTPSA id 4NGx2S4KSZzXDS; Tue, 22 Nov 2022 15:39:44 -0500 (EST) From: Mathieu Desnoyers To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, Thomas Gleixner , "Paul E . McKenney" , Boqun Feng , "H . Peter Anvin" , Paul Turner , linux-api@vger.kernel.org, Christian Brauner , Florian Weimer , David.Laight@ACULAB.COM, carlos@redhat.com, Peter Oskolkov , Alexander Mikhalitsyn , Chris Kennelly , Mathieu Desnoyers Subject: [PATCH 01/30] selftests/rseq: Fix: Fail thread registration when CONFIG_RSEQ=n Date: Tue, 22 Nov 2022 15:39:03 -0500 Message-Id: <20221122203932.231377-2-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221122203932.231377-1-mathieu.desnoyers@efficios.com> References: <20221122203932.231377-1-mathieu.desnoyers@efficios.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org When linking the selftests against a libc which does not handle rseq registration (before 2.35), rseq thread registration silently succeed even with CONFIG_RSEQ=n because it erroneously thinks that libc is handling rseq registration. This is caused by setting the rseq ownership flag only after the rseq_available() check. It should rather be set before the rseq_available() check. Set the rseq_size to 0 (error value) immediately after the rseq_available() check fails rather than in the thread registration functions. Signed-off-by: Mathieu Desnoyers --- tools/testing/selftests/rseq/rseq.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c index 4177f9507bbe..376a73f1ac41 100644 --- a/tools/testing/selftests/rseq/rseq.c +++ b/tools/testing/selftests/rseq/rseq.c @@ -119,9 +119,11 @@ void rseq_init(void) rseq_flags = *libc_rseq_flags_p; return; } - if (!rseq_available()) - return; rseq_ownership = 1; + if (!rseq_available()) { + rseq_size = 0; + return; + } rseq_offset = (void *)&__rseq_abi - rseq_thread_pointer(); rseq_size = sizeof(struct rseq_abi); rseq_flags = 0; -- 2.25.1