From mboxrd@z Thu Jan 1 00:00:00 1970 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id F06BFC87FCA for ; Sat, 26 Jul 2025 07:42:22 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1E4196B0088; Sat, 26 Jul 2025 03:42:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 194A36B0089; Sat, 26 Jul 2025 03:42:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 083CD6B008A; Sat, 26 Jul 2025 03:42:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id ECA496B0088 for ; Sat, 26 Jul 2025 03:42:21 -0400 (EDT) Received: from smtpin08.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 95C281343BE for ; Sat, 26 Jul 2025 07:42:21 +0000 (UTC) X-FDA: 83705622882.08.D87917E Received: from nyc.source.kernel.org (nyc.source.kernel.org [147.75.193.91]) by imf17.hostedemail.com (Postfix) with ESMTP id 2E64940005 for ; Sat, 26 Jul 2025 07:42:20 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=gswPVrHk; spf=pass (imf17.hostedemail.com: domain of rppt@kernel.org designates 147.75.193.91 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1753515740; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=GvTWYWbJnd3Twi29+QTbfJLW1y0MCnmekCUUg3hBGB8=; b=0VtPJLNwlUeLSPtMSulCoXa6MN99taXhEewFLMXN4tEg95qsHsHW/Ttv3XsKKYWUmEqIAw +1Kt6VEf4aaSN2wtrDCGQo/VoIBf88wl/eJMRT9cmsS1u+XRhwV4Y/0pM90IkWUbcT2Peq UUyueV9zd1lLhGCsS1RUlP4zHEYSRt8= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=gswPVrHk; spf=pass (imf17.hostedemail.com: domain of rppt@kernel.org designates 147.75.193.91 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1753515740; a=rsa-sha256; cv=none; b=TjD/r7EKScwBrwz/etBOTVGYMFAvUPl2G/r2rnJXpdn7g38VcN+usxM3v6tPUH7TUzUwJV /Vq6g85BYdhkE+Ozls1eATPH/pL766WyIdupUJreBcQzGmPkYvZsYjW7B7gL3bsGc/iFak qxTIB+KmUVsk0RkNn9iWHtZRO8WMPRE= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 3759EA522AC; Sat, 26 Jul 2025 07:42:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE1BAC4CEED; Sat, 26 Jul 2025 07:42:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753515738; bh=JH80ui6HzMZrysAZcLLCGsZmU6VvUIi+CTfUhFaghYM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gswPVrHk05CTmMSr0rmQsIvvtZGLK84sbkhG7vujS1AtdBJA3iUrxjWoNK98NMpda ONzMzbP/rH/UKNn5AGjuowNFtCTTKJdWOGXj7+cXUBv4SjmXHMqXaZJ89BtyrLgtao sSgrF+ZyPF68pEsFAuSeuuJQHuOzMAPxqSA19FKpb4XI3RynqKvZ9IPmNqv5FW9t1t Itp5hGadOCbL7KVHwUT5/b25VhAxaXhNZif1/oxZZKHKJPwkfA8HoTwEF5HY7nWkCV GGzrb4UeOALjgC2TLEYJIW4g8y91Wkoc30JITbnWHVGq3pXn4NFuyACkQGvB1r09oS 4LB9QaOFiYRwQ== Date: Sat, 26 Jul 2025 10:42:02 +0300 From: Mike Rapoport To: Deepak Gupta Cc: Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Masahiro Yamada , Nathan Chancellor , Nicolas Schier , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Nick Desaulniers , Bill Wendling , Monk Chiang , Kito Cheng , Justin Stitt , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-mm@kvack.org, llvm@lists.linux.dev, rick.p.edgecombe@intel.com, broonie@kernel.org, cleger@rivosinc.com, samitolvanen@google.com, apatel@ventanamicro.com, ajones@ventanamicro.com, conor.dooley@microchip.com, charlie@rivosinc.com, samuel.holland@sifive.com, bjorn@rivosinc.com, fweimer@redhat.com, jeffreyalaw@gmail.com, heinrich.schuchardt@canonical.com, andrew@sifive.com, ved@rivosinc.com Subject: Re: [PATCH 06/11] mm: Introduce ARCH_HAS_KERNEL_SHADOW_STACK Message-ID: References: <20250724-riscv_kcfi-v1-0-04b8fa44c98c@rivosinc.com> <20250724-riscv_kcfi-v1-6-04b8fa44c98c@rivosinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250724-riscv_kcfi-v1-6-04b8fa44c98c@rivosinc.com> X-Stat-Signature: htope3xoh6egj9kjzuspqhyna4xpizkk X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 2E64940005 X-Rspam-User: X-HE-Tag: 1753515740-366255 X-HE-Meta: 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 CHf/LeB9 Vpp3uxvKnqpc69FnMHcKo4YZW6o0Py1fvQV9BmLHkDN3ggeVANdUnXkfIK7GbGHRwjfm0ZvxwrYRFJWY= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Jul 24, 2025 at 04:36:59PM -0700, Deepak Gupta wrote: > commit bcc9d04e74 ("mm: Introduce ARCH_HAS_USER_SHADOW_STACK") introduced > `ARCH_HAS_USER_SHADOW_STACK`. Introducing `ARCH_HAS_KERNEL_SHADOW_STACK` > so that arches can enable hardware assistance for kernel shadow stack. > > If `CONFIG_DYNAMIC_SCS` or `CONFIG_ARCH_HAS_KERNEL_SHADOW_STACK` are > selected, skip compiler flag `-fsanitizer=shadow-call-stack`. > > Signed-off-by: Deepak Gupta > --- > Makefile | 2 +- > mm/Kconfig | 6 ++++++ > 2 files changed, 7 insertions(+), 1 deletion(-) > > diff --git a/Makefile b/Makefile > index 35e6e5240c61..7e3ecca9353d 100644 > --- a/Makefile > +++ b/Makefile > @@ -987,7 +987,7 @@ LDFLAGS_vmlinux += --gc-sections > endif > > ifdef CONFIG_SHADOW_CALL_STACK > -ifndef CONFIG_DYNAMIC_SCS > +ifeq ($(or $(CONFIG_DYNAMIC_SCS),$(CONFIG_ARCH_HAS_KERNEL_SHADOW_STACK)),false) > CC_FLAGS_SCS := -fsanitize=shadow-call-stack > KBUILD_CFLAGS += $(CC_FLAGS_SCS) > KBUILD_RUSTFLAGS += -Zsanitizer=shadow-call-stack > diff --git a/mm/Kconfig b/mm/Kconfig > index 781be3240e21..f295ea611cdb 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -1367,6 +1367,12 @@ config ARCH_HAS_USER_SHADOW_STACK > The architecture has hardware support for userspace shadow call > stacks (eg, x86 CET, arm64 GCS or RISC-V Zicfiss). > > +config ARCH_HAS_KERNEL_SHADOW_STACK > + bool > + help > + The architecture has hardware support for kernel shadow call > + stacks (eg, x86 CET, arm64 GCS or RISC-V Zicfiss). nit: tab and two space for indentation of the help text > + I think both ARCH_HAS_USER_SHADOW_STACK and ARCH_HAS_KERNEL_SHADOW_STACK belong to arch/Kconfig rather than mm/Kconfig > config ARCH_SUPPORTS_PT_RECLAIM > def_bool n > > > -- > 2.43.0 > -- Sincerely yours, Mike.