From patchwork Sun Feb 27 16:28:26 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guo Ren X-Patchwork-Id: 12762008 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 10928C433EF for ; Sun, 27 Feb 2022 16:41:12 +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=XtEMIjpdFjECxx4B9T9m8eze3n2KAWj1zU5ZRK2NYRI=; b=PcogtaOSFenQ6g 0gr2yojgd/LJPT5z9n2s+4JmfQ4KFWTsz1lnpYQF7eBEMf14BRmAm9bXlfr0c6xTduIXpfhDpX94g qXJ8GksucirJtU25kL8HudxRpCvJsUwU5tNzPWP6JrvVSMXuw7KdOAVfq0H8WSVs9SEFd+vavQ/wI fIIkyHWgbHVK7X95FoMUCCEZeiXuursUutiUnFEEkxzsDTO5IM77FcuCiFNH5nh6EsJV3/ku5ke/C xTndslN7WUfGaGr+2fLZqV9XwDAqDyiKdP/I3bZpDsn6TyranN/r/a4ZjgUGzQdvNhFtiGrOZw3l2 FEwcgJg5efZfVmNBUA4w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nOMa8-009ksp-5u; Sun, 27 Feb 2022 16:39:36 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nOMRB-009gH2-GD; Sun, 27 Feb 2022 16:30:23 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 100DE60F46; Sun, 27 Feb 2022 16:30:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 939ACC36AE5; Sun, 27 Feb 2022 16:30:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1645979420; bh=YHBMf6oiN7AKyDQcRFQG6drB0b2sg1GEQLG12pVdvWw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GUC/ztJbtzLNu8llpuROUVaZ3E8NyrDFD8yGwy4K8tYgwlx9qdXJqpr8G1CUuJLuL SQs9N9tJ6CzjqSEvgs9Q+TmAF2tzmIMQd1dQI3B3UPxULabUxNCkqiYJ/czct+Gq8k KuRJjLlgK7fwONb/BsASgTeV3DEsjRYmt6jxDwb7SNswxhumCHq3u385kgUhioQ0Dd GHagwTVSEYjk9hyTY2I+qdz6jk0jJtZtezgxQZil86wm9jjug9Y0MLcB7luMCIyN4l 1F5iB1y8UdGZ0BymhjWAqVsaqnV10+qDR2K6/0tp1NrDeZSHAwDHvotDFZ6/eNGZ9t VccjUEfu+whlw== From: guoren@kernel.org To: guoren@kernel.org, palmer@dabbelt.com, arnd@arndb.de, anup@brainfault.org, gregkh@linuxfoundation.org, liush@allwinnertech.com, wefu@redhat.com, drew@beagleboard.org, wangjunqiang@iscas.ac.cn, hch@lst.de Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, linux-csky@vger.kernel.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-parisc@vger.kernel.org, linux-mips@vger.kernel.org, linux-arm-kernel@lists.infradead.org, x86@kernel.org, Guo Ren Subject: [PATCH V7 15/20] riscv: compat: Add hw capability check for elf Date: Mon, 28 Feb 2022 00:28:26 +0800 Message-Id: <20220227162831.674483-16-guoren@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220227162831.674483-1-guoren@kernel.org> References: <20220227162831.674483-1-guoren@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220227_083021_681092_A3CC9188 X-CRM114-Status: GOOD ( 11.87 ) X-BeenThere: linux-arm-kernel@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-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Guo Ren Detect hardware COMPAT (32bit U-mode) capability in rv64. If not support COMPAT mode in hw, compat_elf_check_arch would return false by compat_binfmt_elf.c Signed-off-by: Guo Ren Signed-off-by: Guo Ren Cc: Arnd Bergmann Cc: Christoph Hellwig --- arch/riscv/include/asm/elf.h | 3 ++- arch/riscv/kernel/process.c | 26 ++++++++++++++++++++++++++ 2 files changed, 28 insertions(+), 1 deletion(-) diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h index aee40040917b..3a4293dc7229 100644 --- a/arch/riscv/include/asm/elf.h +++ b/arch/riscv/include/asm/elf.h @@ -40,7 +40,8 @@ * elf64_hdr e_machine's offset are different. The checker is * a little bit simple compare to other architectures. */ -#define compat_elf_check_arch(x) ((x)->e_machine == EM_RISCV) +extern bool compat_elf_check_arch(Elf32_Ehdr *hdr); +#define compat_elf_check_arch compat_elf_check_arch #define CORE_DUMP_USE_REGSET #define ELF_EXEC_PAGESIZE (PAGE_SIZE) diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index 54787ca9806a..7bbe4dd95e85 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -83,6 +83,32 @@ void show_regs(struct pt_regs *regs) dump_backtrace(regs, NULL, KERN_DEFAULT); } +#ifdef CONFIG_COMPAT +static bool compat_mode_supported __read_mostly; + +bool compat_elf_check_arch(Elf32_Ehdr *hdr) +{ + return compat_mode_supported && hdr->e_machine == EM_RISCV; +} + +static int __init compat_mode_detect(void) +{ + unsigned long tmp = csr_read(CSR_STATUS); + + csr_write(CSR_STATUS, (tmp & ~SR_UXL) | SR_UXL_32); + compat_mode_supported = + (csr_read(CSR_STATUS) & SR_UXL) == SR_UXL_32; + + csr_write(CSR_STATUS, tmp); + + pr_info("riscv: ELF compat mode %s", + compat_mode_supported ? "supported" : "failed"); + + return 0; +} +early_initcall(compat_mode_detect); +#endif + void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp) {