From patchwork Thu Feb 24 08:54:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guo Ren X-Patchwork-Id: 12758153 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 9A376C433FE for ; Thu, 24 Feb 2022 09:08:45 +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=1YyPAKkFY36Rn9 /K66pwhIh1FRUW2htgs3FRDDq/ncDZyZoeJE33ctgkdU4dAyzNTz5jYggBoZ9Xa+KYcE6RaZ0LLWG qYrI3d0NoOZFBpLzHVoiVuULm9pbHhovQ7UbSX+t/vtOcxl895gNZn0WBhr3YvydloUslr/HCxJ5x AieFjAj75dW6Aw6lo6t8rcnUaRxq8Iu0W7Lh8bZkcAQHWLRanm46sitLif9DcMSCUwNAJDXFqxcfp nfwZqw3i5+G805ioJIXwms+GoiUOi7cZS5DGkYrRcZuI66CB8HuRV1TwzejxVqXZgr9uDkCZ/fjji 06w7mC7bGSGo0PIPWX2g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nNA5Y-00HUun-Nm; Thu, 24 Feb 2022 09:07:06 +0000 Received: from ams.source.kernel.org ([2604:1380:4601:e00::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nN9vd-00HPB5-Lk; Thu, 24 Feb 2022 08:56:51 +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 ams.source.kernel.org (Postfix) with ESMTPS id 3C0AAB82359; Thu, 24 Feb 2022 08:56:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F0920C340E9; Thu, 24 Feb 2022 08:56:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1645693007; bh=YHBMf6oiN7AKyDQcRFQG6drB0b2sg1GEQLG12pVdvWw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y3Y/NRqVQxVUTtAB3/fzxTf4Hl9aCJrxHdt0wXwEeIMlkVHaKweQZn8JFLnXvIqxa SX6XbreT2NV6+b1WcqW4Zu5wIM0bBkRlIi10wOkKWjFsfdXOuh6za3cotaPYabiA/G aG2gasqAZs8weiOTr7UF60qeqNe91bptGEzLhpzJZQldkwmD6/bzyGLJvF76WCPDBm 3mDt2h02smrKjcxOVntP+ejdWnThEu8gaNIB3mqkEZts8qizc91DHM1ZF5oGfizWs3 x+VkJzLazXZ869aixl7r/HQDAIDzqINeM2hNIMZMowYzrzsVIs3koMf1ksadaLD+DX EmfJ/sg5kGW3w== 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 V6 15/20] riscv: compat: Add hw capability check for elf Date: Thu, 24 Feb 2022 16:54:05 +0800 Message-Id: <20220224085410.399351-16-guoren@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220224085410.399351-1-guoren@kernel.org> References: <20220224085410.399351-1-guoren@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220224_005650_099120_A074F592 X-CRM114-Status: GOOD ( 12.17 ) 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) {