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=-16.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,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 AC257C433FE for ; Fri, 10 Sep 2021 00:43:35 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5D99060C40 for ; Fri, 10 Sep 2021 00:43:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 5D99060C40 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4H5HDQ0ClFz3cBs for ; Fri, 10 Sep 2021 10:43:34 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=t8tKRqY7; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=198.145.29.99; helo=mail.kernel.org; envelope-from=sashal@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=t8tKRqY7; dkim-atps=neutral Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4H5Gn96TwRz3cG1 for ; Fri, 10 Sep 2021 10:23:25 +1000 (AEST) Received: by mail.kernel.org (Postfix) with ESMTPSA id 67D5D60FDA; Fri, 10 Sep 2021 00:23:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631233404; bh=lZkivQP3DofMjGxIe08apnirKRtBtazACpanOtt5U3E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t8tKRqY7wX14GIZLP6o+linu0jCKEvJwTA1EOafPMSS461RogyBbf8NL1ZUMHeJ6i fFXy0ypOpkG7kMw9ism84p3Cy0+gUXSOC3wElLqf7X5jC6krEgVYmoklUCYyeHJLoy VwFJFrmeOm0RKlkAcrXXQLQ/NlP4niVHUrsJ+H1vEYzhLWeka1lm4vxIHzx2AufkZF aDODOkJIQoBCXpWythi1qDZLE2H7iQVj3xzZoKrBZuj/DB4El2YH38J5AScqXJR//o vMaHk+8Fb2JSitqEBEYAD3EE6XymTF/K6elyy/u3/F1Ax5EW4AtS0EcLxxiSQ2XN3J G8bbkB6rfsEWw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 10/19] powerpc/32: indirect function call use bctrl rather than blrl in ret_from_kernel_thread Date: Thu, 9 Sep 2021 20:23:00 -0400 Message-Id: <20210910002309.176412-10-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210910002309.176412-1-sashal@kernel.org> References: <20210910002309.176412-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sasha Levin , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" From: Christophe Leroy [ Upstream commit 113ec9ccc8049c3772f0eab46b62c5d6654c09f7 ] Copied from commit 89bbe4c798bc ("powerpc/64: indirect function call use bctrl rather than blrl in ret_from_kernel_thread") blrl is not recommended to use as an indirect function call, as it may corrupt the link stack predictor. This is not a performance critical path but this should be fixed for consistency. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/91b1d242525307ceceec7ef6e832bfbacdd4501b.1629436472.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin --- arch/powerpc/kernel/entry_32.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index a2999cd73a82..ea1c00bc6ced 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -468,10 +468,10 @@ ret_from_fork: ret_from_kernel_thread: REST_NVGPRS(r1) bl schedule_tail - mtlr r14 + mtctr r14 mr r3,r15 PPC440EP_ERR42 - blrl + bctrl li r3,0 b ret_from_syscall -- 2.30.2