From patchwork Tue Apr 5 07:13:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guo Ren X-Patchwork-Id: 12801114 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 99C6DC433EF for ; Tue, 5 Apr 2022 07:17:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231546AbiDEHTJ (ORCPT ); Tue, 5 Apr 2022 03:19:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36212 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231547AbiDEHSR (ORCPT ); Tue, 5 Apr 2022 03:18:17 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A7C8891AFB; Tue, 5 Apr 2022 00:15:27 -0700 (PDT) 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 3B63EB81BAE; Tue, 5 Apr 2022 07:15:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F3E12C340EE; Tue, 5 Apr 2022 07:15:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1649142924; bh=qts+XhXf9HFBnxM/+mMxHMF9ldoQz8C/1qg2SBDs/7s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RywdVYOy18ZaA/hNwFHqKY/LT0HvTTalDyj0/M7FY0/SrlX5lfa5/bqbVtagr5bDJ mIFlzNjxh+uEHqvAozQepWLb+IpWEH7OfZyH6rSej/BxR/eFnT2ZX+lm4AGIYV6jL1 LK8zYzKSAJwrxRBOD6hem/JwSER6AasuiLvN07j96ZPYqm/bZavqWXsLKkPpU/q8CL vHhGRUVP5/A3uKHepxn2CdZdekrRdEwma2j0xxQrMJ693LTtpJ8H/1URKbHTq1U9Eh kULJ1WOfyfcc9zK2xzxgYvbGreJIGoPrqZ5ATk+zFNsFCpzuQmVdsNdQq+ntAlZ6Bp YguqIvGpghiWg== From: guoren@kernel.org To: guoren@kernel.org, palmer@dabbelt.com, arnd@arndb.de, gregkh@linuxfoundation.org, hch@lst.de, nathan@kernel.org, naresh.kamboju@linaro.org Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.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, heiko@sntech.de, Guo Ren Subject: [PATCH V12 20/20] riscv: compat: Add COMPAT Kbuild skeletal support Date: Tue, 5 Apr 2022 15:13:14 +0800 Message-Id: <20220405071314.3225832-21-guoren@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220405071314.3225832-1-guoren@kernel.org> References: <20220405071314.3225832-1-guoren@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org From: Guo Ren Adds initial skeletal COMPAT Kbuild (Running 32bit U-mode on 64bit S-mode) support. - Setup kconfig & dummy functions for compiling. - Implement compat_start_thread by the way. Signed-off-by: Guo Ren Signed-off-by: Guo Ren Reviewed-by: Arnd Bergmann Tested-by: Heiko Stuebner Cc: Palmer Dabbelt --- arch/riscv/Kconfig | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 00fd9c548f26..def9798e9675 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -76,6 +76,7 @@ config RISCV select HAVE_ARCH_KGDB if !XIP_KERNEL select HAVE_ARCH_KGDB_QXFER_PKT select HAVE_ARCH_MMAP_RND_BITS if MMU + select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT select HAVE_ARCH_SECCOMP_FILTER select HAVE_ARCH_TRACEHOOK select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU @@ -127,12 +128,18 @@ config ARCH_MMAP_RND_BITS_MIN default 18 if 64BIT default 8 +config ARCH_MMAP_RND_COMPAT_BITS_MIN + default 8 + # max bits determined by the following formula: # VA_BITS - PAGE_SHIFT - 3 config ARCH_MMAP_RND_BITS_MAX default 24 if 64BIT # SV39 based default 17 +config ARCH_MMAP_RND_COMPAT_BITS_MAX + default 17 + # set if we run in machine mode, cleared if we run in supervisor mode config RISCV_M_MODE bool @@ -394,6 +401,18 @@ config CRASH_DUMP For more details see Documentation/admin-guide/kdump/kdump.rst +config COMPAT + bool "Kernel support for 32-bit U-mode" + default 64BIT + depends on 64BIT && MMU + help + This option enables support for a 32-bit U-mode running under a 64-bit + kernel at S-mode. riscv32-specific components such as system calls, + the user helper functions (vdso), signal rt_frame functions and the + ptrace interface are handled appropriately by the kernel. + + If you want to execute 32-bit userspace applications, say Y. + endmenu menu "Boot options"