From patchwork Thu Jan 20 07:39:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guo Ren X-Patchwork-Id: 12718372 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 C435DC433EF for ; Thu, 20 Jan 2022 07:41:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244282AbiATHlw (ORCPT ); Thu, 20 Jan 2022 02:41:52 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:35234 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239682AbiATHld (ORCPT ); Thu, 20 Jan 2022 02:41:33 -0500 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 F2284B81CEE; Thu, 20 Jan 2022 07:41:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36F63C340E5; Thu, 20 Jan 2022 07:41:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1642664490; bh=WKKFJwT/zbXr14n62tvJaQ2yJAifn6O6yK5rrbY11Yk=; h=From:To:Cc:Subject:Date:From; b=rlwv4PiHxpQ4Q8AXZLu2v5vBM919T2dC3MSYdBA0Yl2BADAVfndtYdvnbfrYXfEnK ugD2B/y7c61Yf5LrmW1BLTBliuh+NqzCjBJlQ8h7J6rki71bb7EFG891kn4u5fWPBq nDeplJX4XNQoKLydFe9sSLfo16UtpVvVG8yX00ulQ83bSWakalEJZ8ajWO4Rbqy0cz 463MocL0EbRCotDIMRqjHV1/lK7Lwmzsz37NZx3EQqCcM28fcIUriMcsSTkUGkP8BT 9GcWEosJfFD1Q2miK4xR1Le36jnGulPVkfGWXJ5/KaN4YjXYxLpVJksLvVbzJ0EhE2 AhxiKxd2W0awg== 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, hch@infradead.org Cc: 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, inux-parisc@vger.kernel.org, linux-mips@vger.kernel.org, linux-arm-kernel@lists.infradead.org, x86@kernel.org, Guo Ren Subject: [PATCH V3 16/17] riscv: compat: Add COMPAT Kbuild skeletal support Date: Thu, 20 Jan 2022 15:39:09 +0800 Message-Id: <20220120073911.99857-17-guoren@kernel.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org From: Guo Ren Adds initial skeletal COMPAT Kbuild (Runing 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 Cc: Arnd Bergmann Reviewed-by: Arnd Bergmann --- arch/riscv/Kconfig | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 4602cfe92a20..d16ab3af3b34 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -73,6 +73,7 @@ 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 @@ -123,12 +124,18 @@ 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 @@ -428,6 +435,18 @@ 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"