From patchwork Fri Jan 21 16:36:08 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heiko Stuebner X-Patchwork-Id: 12719917 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 A993EC433FE for ; Fri, 21 Jan 2022 16:37:30 +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=GdWysZPljUj6K/px/4gj5KTarNI9Bz69w5tysFl4HFc=; b=xzo332/1oxjZlA nWzQrFGL2ER/BAX8LACwAJE47iAPOhuDwiwO6uJDhsb4XK1gbcdx0MetK25Fx+e5sLUhc23xzOgc8 QcnxUhzHbAz0LMZLBXIsOh9UTiOc8f0IIXOIsOgXHBFI+XUFkPFh7A/4IU+G7GF/6SaQtrp+mxTN9 1jnA1TvEpHbuy28O/A/qpLLoFJzbXOZXwSZgP3trOYMuY91sY82ckgHsRE+seF/Z/xvzj9u4Ob6Li 4wrUBZGIlOm3Unl8xv3hV97Ab+WKfx8i0FdulqRzkHJHaaJFCGuO4XZeVSfBYu6toJWvnSrOa3UcD VPEDFcNb5urKqc8OHilQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nAwuZ-00FZXj-81; Fri, 21 Jan 2022 16:37:15 +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 1nAwuV-00FZTn-1q for linux-riscv@lists.infradead.org; Fri, 21 Jan 2022 16:37:12 +0000 Received: from p508fcef5.dip0.t-ipconnect.de ([80.143.206.245] helo=phil.fritz.box) by gloria.sntech.de with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1nAwuI-0008GA-QQ; Fri, 21 Jan 2022 17:36:58 +0100 From: Heiko Stuebner To: palmer@dabbelt.com, paul.walmsley@sifive.com, aou@eecs.berkeley.edu Cc: linux-riscv@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, robh+dt@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, dlustig@nvidia.com, gfavor@ventanamicro.com, andrea.mondelli@huawei.com, behrensj@mit.edu, xinhaoqu@huawei.com, huffman@cadence.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 v5 04/14] riscv: implement module alternatives Date: Fri, 21 Jan 2022 17:36:08 +0100 Message-Id: <20220121163618.351934-5-heiko@sntech.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220121163618.351934-1-heiko@sntech.de> References: <20220121163618.351934-1-heiko@sntech.de> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220121_083711_130280_69232CAA X-CRM114-Status: GOOD ( 17.01 ) 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 This allows alternatives to also be applied when loading modules and follows the implementation of other architectures (e.g. arm64). Signed-off-by: Heiko Stuebner --- arch/riscv/include/asm/alternative.h | 3 ++- arch/riscv/kernel/alternative.c | 16 ++++++++++++--- arch/riscv/kernel/module.c | 29 ++++++++++++++++++++++++++++ 3 files changed, 44 insertions(+), 4 deletions(-) diff --git a/arch/riscv/include/asm/alternative.h b/arch/riscv/include/asm/alternative.h index 811bdd8027db..f0657b1b3174 100644 --- a/arch/riscv/include/asm/alternative.h +++ b/arch/riscv/include/asm/alternative.h @@ -18,8 +18,10 @@ #include #define RISCV_ALTERNATIVES_BOOT 0 /* alternatives applied during regular boot */ +#define RISCV_ALTERNATIVES_MODULE 1 /* alternatives applied during module-init */ void __init apply_boot_alternatives(void); +void apply_module_alternatives(void *start, size_t length); struct alt_entry { void *old_ptr; /* address of original instruciton or data */ @@ -37,6 +39,5 @@ struct errata_checkfunc_id { void sifive_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, unsigned long archid, unsigned long impid, unsigned int stage); - #endif #endif diff --git a/arch/riscv/kernel/alternative.c b/arch/riscv/kernel/alternative.c index ead00c508266..e1849faa2fa1 100644 --- a/arch/riscv/kernel/alternative.c +++ b/arch/riscv/kernel/alternative.c @@ -7,6 +7,7 @@ */ #include +#include #include #include #include @@ -58,9 +59,9 @@ static void __init init_alternative(void) * a feature detect on the boot CPU). No need to worry about other CPUs * here. */ -static void __init _apply_alternatives(struct alt_entry *begin, - struct alt_entry *end, - unsigned int stage) +static void __init_or_module _apply_alternatives(struct alt_entry *begin, + struct alt_entry *end, + unsigned int stage) { if (!vendor_patch_func) return; @@ -81,3 +82,12 @@ void __init apply_boot_alternatives(void) (struct alt_entry *)__alt_end, RISCV_ALTERNATIVES_BOOT); } + +#ifdef CONFIG_MODULES +void apply_module_alternatives(void *start, size_t length) +{ + _apply_alternatives((struct alt_entry *)start, + (struct alt_entry *)(start + length), + RISCV_ALTERNATIVES_MODULE); +} +#endif diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c index 68a9e3d1fe16..a778abd5b8b9 100644 --- a/arch/riscv/kernel/module.c +++ b/arch/riscv/kernel/module.c @@ -11,6 +11,7 @@ #include #include #include +#include #include static int apply_r_riscv_32_rela(struct module *me, u32 *location, Elf_Addr v) @@ -416,3 +417,31 @@ void *module_alloc(unsigned long size) __builtin_return_address(0)); } #endif + +static const Elf_Shdr *find_section(const Elf_Ehdr *hdr, + const Elf_Shdr *sechdrs, + const char *name) +{ + const Elf_Shdr *s, *se; + const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; + + for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++) { + if (strcmp(name, secstrs + s->sh_name) == 0) + return s; + } + + return NULL; +} + +int module_finalize(const Elf_Ehdr *hdr, + const Elf_Shdr *sechdrs, + struct module *me) +{ + const Elf_Shdr *s; + + s = find_section(hdr, sechdrs, ".alternative"); + if (s) + apply_module_alternatives((void *)s->sh_addr, s->sh_size); + + return 0; +}