From patchwork Thu Mar 24 00:07:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Heiko_St=C3=BCbner?= X-Patchwork-Id: 12790266 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 71931C433FE for ; Thu, 24 Mar 2022 00:07:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=l0RC/OgFQ4j6rmnmoxQmR0X0vVySW4/Dqd9qMcyi5Yk=; b=hKSHPATMOoXSaz 04K8ssfXRQSJQP6Gjz5pdrtzduV6GNomVo31mYQRani7slhvvkgkQuNDlWwl5ygJ3jrGkY7NxlyNd maPNIgJvq0+lmSPrnv9echPiIsCfUG4dnPqmtFG60+2+LeCPql7tZaceZw+rBLVpOAPGyek2Ik7qx tSXGu9vGec5s//lQoRJw14tt9u81yor4lLdc0WcAAek04w/JBsdVphkJBOsPsFIpF9oM6osYelBf7 rxjCnVgWGHarrm4R8PER23OqaNMdQBkoF1XjLHZRbj1Mykrek4xxkS94gGteWKRMw+a1v86oM6n0t PGd7reR1x7f4lvxUT1lg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nXB0z-00F9fL-Dg; Thu, 24 Mar 2022 00:07:45 +0000 Received: from gloria.sntech.de ([185.11.138.130]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nXB0s-00F9bS-EV for linux-riscv@lists.infradead.org; Thu, 24 Mar 2022 00:07:41 +0000 Received: from ip5b412258.dynamic.kabel-deutschland.de ([91.65.34.88] helo=phil.lan) by gloria.sntech.de with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1nXB0p-00055s-EF; Thu, 24 Mar 2022 01:07:35 +0100 From: Heiko Stuebner To: palmer@dabbelt.com, paul.walmsley@sifive.com, aou@eecs.berkeley.edu Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, wefu@redhat.com, liush@allwinnertech.com, guoren@kernel.org, atishp@atishpatra.org, anup@brainfault.org, drew@beagleboard.org, hch@lst.de, arnd@arndb.de, wens@csie.org, maxime@cerno.tech, gfavor@ventanamicro.com, andrea.mondelli@huawei.com, behrensj@mit.edu, xinhaoqu@huawei.com, mick@ics.forth.gr, allen.baum@esperantotech.com, jscheid@ventanamicro.com, rtrauben@gmail.com, samuel@sholland.org, cmuellner@linux.com, philipp.tomsich@vrull.eu, Heiko Stuebner Subject: [PATCH v8 07/14] riscv: prevent compressed instructions in alternatives Date: Thu, 24 Mar 2022 01:07:03 +0100 Message-Id: <20220324000710.575331-8-heiko@sntech.de> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220324000710.575331-1-heiko@sntech.de> References: <20220324000710.575331-1-heiko@sntech.de> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220323_170738_617399_6A66AC79 X-CRM114-Status: UNSURE ( 9.90 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Instructions are opportunistically compressed by the RISC-V assembler when possible, but in alternatives-blocks both the old and new content need to be the same size, so having the toolchain do somewhat random optimizations will cause strange side-effects like "attempt to move .org backwards" compile-time errors. Already a simple "and" used in alternatives assembly will cause these mismatched code sizes. So prevent compressed instructions to be generated in alternatives- code and use option-push and -pop to only limit this to the relevant code blocks Signed-off-by: Heiko Stuebner Reviewed-by: Christoph Hellwig --- arch/riscv/include/asm/alternative-macros.h | 24 +++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/arch/riscv/include/asm/alternative-macros.h b/arch/riscv/include/asm/alternative-macros.h index 25b4559d743b..3c12396e247c 100644 --- a/arch/riscv/include/asm/alternative-macros.h +++ b/arch/riscv/include/asm/alternative-macros.h @@ -21,7 +21,11 @@ .popsection .subsection 1 888 : + .option push + .option norvc + .option norelax \new_c + .option pop 889 : .previous .org . - (889b - 888b) + (887b - 886b) @@ -31,7 +35,11 @@ .macro __ALTERNATIVE_CFG old_c, new_c, vendor_id, errata_id, enable 886 : + .option push + .option norvc + .option norelax \old_c + .option pop 887 : ALT_NEW_CONTENT \vendor_id, \errata_id, \enable, \new_c .endm @@ -42,7 +50,11 @@ .macro __ALTERNATIVE_CFG_2 old_c, new_c_1, vendor_id_1, errata_id_1, enable_1, \ new_c_2, vendor_id_2, errata_id_2, enable_2 886 : + .option push + .option norvc + .option norelax \old_c + .option pop 887 : ALT_NEW_CONTENT \vendor_id_1, \errata_id_1, \enable_1, \new_c_1 ALT_NEW_CONTENT \vendor_id_2, \errata_id_2, \enable_2, \new_c_2 @@ -72,7 +84,11 @@ ".popsection\n" \ ".subsection 1\n" \ "888 :\n" \ + ".option push\n" \ + ".option norvc\n" \ + ".option norelax\n" \ new_c "\n" \ + ".option pop\n" \ "889 :\n" \ ".previous\n" \ ".org . - (887b - 886b) + (889b - 888b)\n" \ @@ -81,7 +97,11 @@ #define __ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, enable) \ "886 :\n" \ + ".option push\n" \ + ".option norvc\n" \ + ".option norelax\n" \ old_c "\n" \ + ".option pop\n" \ "887 :\n" \ ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c) @@ -91,7 +111,11 @@ #define __ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, errata_id_1, enable_1, \ new_c_2, vendor_id_2, errata_id_2, enable_2) \ "886 :\n" \ + ".option push\n" \ + ".option norvc\n" \ + ".option norelax\n" \ old_c "\n" \ + ".option pop\n" \ "887 :\n" \ ALT_NEW_CONTENT(vendor_id_1, errata_id_1, enable_1, new_c_1) \ ALT_NEW_CONTENT(vendor_id_2, errata_id_2, enable_2, new_c_2)