From patchwork Mon Mar 7 20:53:04 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: 12772352 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 4B095C4332F for ; Mon, 7 Mar 2022 20:53:48 +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=njhy3Eco9XEsTIbe0TXRe71huvWVEMc6qxlIVYjmmiM=; b=n3JREMLNMDhqJW tRIQ518MEA/KFDJrnNYpdM/vmwkP2F7kxje2LHj3EBYUn1d46w4N6TAB1LQCpWGDV7S0DGV0o86Tg qk6Ufz09tZQJOPosioSjGrcZt1/QzCp9BGemIKbhkxWABBNCkm64QH1cd/Rov+IbooPSVtF4G2ZCU xXtuGD3uep/Z7UirCip4f/Iid2PFOR6qVhl1R9mNO+GXkMRXTBocgP1kmSE4kxa/dLIij0fR9lx3N Y0wh++DBCnpxbg1l4xHE62yHucUalF1kkrmDjZu/akrBlflDIlbKGUBmoL+DcjN8ahfaxG6O13a26 5AH/9syVOEPWBnmmoDug==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nRKMM-001XFD-0V; Mon, 07 Mar 2022 20:53:38 +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 1nRKM6-001X5f-SK for linux-riscv@lists.infradead.org; Mon, 07 Mar 2022 20:53:25 +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 1nRKM3-0002DJ-Qu; Mon, 07 Mar 2022 21:53:19 +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 v7 07/13] riscv: prevent compressed instructions in alternatives Date: Mon, 7 Mar 2022 21:53:04 +0100 Message-Id: <20220307205310.1905628-8-heiko@sntech.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220307205310.1905628-1-heiko@sntech.de> References: <20220307205310.1905628-1-heiko@sntech.de> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220307_125323_033833_7DE869A3 X-CRM114-Status: GOOD ( 10.32 ) 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 --- arch/riscv/include/asm/alternative-macros.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/arch/riscv/include/asm/alternative-macros.h b/arch/riscv/include/asm/alternative-macros.h index c0fb11fad631..3a52884bf23d 100644 --- a/arch/riscv/include/asm/alternative-macros.h +++ b/arch/riscv/include/asm/alternative-macros.h @@ -19,7 +19,10 @@ .popsection .subsection 1 888 : + .option push + .option norvc \new_c + .option pop 889 : .previous .org . - (889b - 888b) + (887b - 886b) @@ -29,7 +32,10 @@ .macro __ALTERNATIVE_CFG old_c, new_c, vendor_id, errata_id, enable 886 : + .option push + .option norvc \old_c + .option pop 887 : ALT_NEW_CONTENT \vendor_id, \errata_id, \enable, \new_c .endm @@ -40,7 +46,10 @@ .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 \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 @@ -70,7 +79,10 @@ ".popsection\n" \ ".subsection 1\n" \ "888 :\n" \ + ".option push\n" \ + ".option norvc\n" \ new_c "\n" \ + ".option pop\n" \ "889 :\n" \ ".previous\n" \ ".org . - (887b - 886b) + (889b - 888b)\n" \ @@ -79,7 +91,10 @@ #define __ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, enable) \ "886 :\n" \ + ".option push\n" \ + ".option norvc\n" \ old_c "\n" \ + ".option pop\n" \ "887 :\n" \ ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c) @@ -89,7 +104,10 @@ #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" \ 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)