From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f179.google.com (mail-oi1-f179.google.com [209.85.167.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 062A4156DB for ; Sat, 9 Dec 2023 22:28:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="wGgwNhiP" Received: by mail-oi1-f179.google.com with SMTP id 5614622812f47-3b9e7f4a0d7so1557538b6e.1 for ; Sat, 09 Dec 2023 14:28:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1702160904; x=1702765704; darn=lists.linux.dev; h=mime-version:message-id:date:in-reply-to:subject:cc:to:from :user-agent:references:from:to:cc:subject:date:message-id:reply-to; bh=GIZ+mcVI5qd9xzhqd2Lq/djPmsscI/1vsqmZHAfk8NA=; b=wGgwNhiPoV4/q80dwUk3l4dMWkY1IxSUgifaUta1u7q6Hb4b2P3609kEWSOpysFsaH 7z3Oc2pMMh/GRhVQ4/RG7FQuRiD5MIZjydhvB5hUJHUuDjuMLMGjReFaIx3UHHJBzSq0 SuLvUEhEe5o4U8AdS7gyMRsOAWR9znuINKnSGNGyac6AD3lRuJWYiQB5PzfuR4JxZ/mY U8Ue51dly79cgjqyJXTmMk+DUYGPSTVEv/XlhDai056GI0fNxeXeHos23PhahRrrcppY q7LnCl/vyIbzR+1aLq/ss8EwfVLOE6Uo3rkIRfSKXf86ImvdH5BxKLv0aO1RBhsswYOA +nTA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702160904; x=1702765704; h=mime-version:message-id:date:in-reply-to:subject:cc:to:from :user-agent:references:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=GIZ+mcVI5qd9xzhqd2Lq/djPmsscI/1vsqmZHAfk8NA=; b=jjg9HxuVONBo7YLYm1lu586tyStko+Zcalv0Yw8HyEwyFmQ/UZ3K1zc3EZTnxP5r7/ 63IFE3UoSubRv8rr2ecteoQQtM4hV+CkjfD0f7k3Jtinjd52gvWadGTmmbjDibFhTDqW Z2yTlMxfkppGLH/zEQcj0stDWQNIaxwbS1i9XTQkN01IkLZb63V9kI1ZhtNtE49ZBxtl fT6oHq8+RFrcCc5rEDpM970tdTSvu1UFNZG1F/Jr/bG+7UIsXXll3OKyKPvZpJjEb6m2 qRVODxYghb2Y75M0bPWx33FGi4/WR8fVzhHTOZmq28PgZ9DcXhZ8MfLPdINwKhILtLVM RjQQ== X-Gm-Message-State: AOJu0Yw7Fcz0RMCe3Nbtn9hF3yGky//XlyTJ+DM4fO6c+NeFNIMpZTMg xPR5xKr3lfuV6wI1oh40ZzU/sg== X-Google-Smtp-Source: AGHT+IHe/3Q7T7mqAS39AMZy9ESnpkNFM6q37u24Z3u046keYsm8BlHmxnJkG9/CppRHC9PxpHjPRw== X-Received: by 2002:a05:6808:21a6:b0:3b9:e87b:d963 with SMTP id be38-20020a05680821a600b003b9e87bd963mr2922446oib.85.1702160903962; Sat, 09 Dec 2023 14:28:23 -0800 (PST) Received: from localhost ([2804:14d:7e39:8470:ded6:9593:9f4f:5c29]) by smtp.gmail.com with ESMTPSA id h17-20020aa786d1000000b006ce7ed5ba42sm3794269pfo.171.2023.12.09.14.28.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 09 Dec 2023 14:28:23 -0800 (PST) References: <20231122-arm64-gcs-v7-0-201c483bd775@kernel.org> <20231122-arm64-gcs-v7-25-201c483bd775@kernel.org> User-agent: mu4e 1.10.8; emacs 29.1 From: Thiago Jung Bauermann To: Mark Brown Cc: Catalin Marinas , Will Deacon , Jonathan Corbet , Andrew Morton , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Arnd Bergmann , Oleg Nesterov , Eric Biederman , Kees Cook , Shuah Khan , "Rick P. Edgecombe" , Deepak Gupta , Ard Biesheuvel , Szabolcs Nagy , "H.J. Lu" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Florian Weimer , Christian Brauner , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH v7 25/39] arm64/signal: Expose GCS state in signal frames In-reply-to: <20231122-arm64-gcs-v7-25-201c483bd775@kernel.org> Date: Sat, 09 Dec 2023 19:28:21 -0300 Message-ID: <87sf4bf1tm.fsf@linaro.org> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain Mark Brown writes: > +static int preserve_gcs_context(struct gcs_context __user *ctx) > +{ > + int err = 0; > + u64 gcspr; > + > + /* > + * We will add a cap token to the frame, include it in the > + * GCSPR_EL0 we report to support stack switching via > + * sigreturn. > + */ > + gcs_preserve_current_state(); > + gcspr = current->thread.gcspr_el0; > + if (task_gcs_el0_enabled(current)) > + gcspr -= 8; > + > + __put_user_error(GCS_MAGIC, &ctx->head.magic, err); > + __put_user_error(sizeof(*ctx), &ctx->head.size, err); > + __put_user_error(gcspr, &ctx->gcspr, err); > + __put_user_error(current->thread.gcs_el0_mode, > + &ctx->features_enabled, err); Other preserve__context() functions zero the reserved fields in ctx. I suggest doing the same here. It helps with backward compatibility. > + > + return err; > +} -- Thiago 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 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 5C9F0C4167B for ; Sat, 9 Dec 2023 22:28:40 +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:Message-ID:Date: In-reply-to:Subject:Cc:To:From:References:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=KDEOdd4iAgDEQzuMZuUFl7VMr1b8ZEQLG3VBHKZbeHg=; b=xYPODX2LOPkA7u0eXviW8om1C2 GAYNwrj2hiEexCnfwBOxbxz2MAVc6fWXOraWYBbLndQ5+1sCer6x5bGIqj0lzMaMBs3GD16FmcuBZ OBgr3ZQVTZD9yumKf02QW/PT3Bv4azimrwk6jahRc0ChBsUl8tRW4p0XRsZFuWVWZA4gdRPeZm24c 0WOCQQ2BN4tMRwrVyo56X/frfURlXH6Uk6bu18rHY9JS2xN0dgnNnxJgrExMw24dM1sOwvnjgn6YW IXTKupU+vGiBfNmEY5gcIpzI528HuRCeToF5LcKElLnebYI9YG8dWRINOdTodJxBhHjUUlnocC2m0 rib6ElzA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rC5oE-000ckX-1u; Sat, 09 Dec 2023 22:28:30 +0000 Received: from mail-oi1-x22c.google.com ([2607:f8b0:4864:20::22c]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rC5oA-000chi-0q for linux-riscv@lists.infradead.org; Sat, 09 Dec 2023 22:28:28 +0000 Received: by mail-oi1-x22c.google.com with SMTP id 5614622812f47-3b9ef61b6b8so1229939b6e.3 for ; Sat, 09 Dec 2023 14:28:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1702160904; x=1702765704; darn=lists.infradead.org; h=mime-version:message-id:date:in-reply-to:subject:cc:to:from :user-agent:references:from:to:cc:subject:date:message-id:reply-to; bh=GIZ+mcVI5qd9xzhqd2Lq/djPmsscI/1vsqmZHAfk8NA=; b=fcAyvtgr/P86KD7EgiiDUsSe6KWHQ4KjUcRbRRXa2zj8VDNy/fMl6EAm3RKHbi40Bp YvtfOopHK9uF0uUpFfNh0L47hi0UlsrUnjTPyvxeWudU0Keb3GkX5pshZmuu3ELIWfHi IhPPA9Z3CxDkocYErq6Yl2kwxItys//eielvG8TQMkWh57MnR8igcbQh1lyyiNeQyCBN wUK34T9nS9Lxzw5oRNj7YorTeHYI/45EEi4NgpwK60aNaz7CF6LyTL/ABfoU1fT9AH/s O77bBcuXg7Qrr8CN2yrSu+8ZXDgQ53X6dzM5At8jZqYlTiw2zfadtCzc1H4F9UADE5j1 jm3w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702160904; x=1702765704; h=mime-version:message-id:date:in-reply-to:subject:cc:to:from :user-agent:references:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=GIZ+mcVI5qd9xzhqd2Lq/djPmsscI/1vsqmZHAfk8NA=; b=SPdnrdz3LAjY6qG0+JRdztEFoAZieESu4VFFlv2CYDw5l/XVflhSd/+iOzYXANa+rf iimb53IAeCMcG2bERL8j6qok9zfxe4lRq0+ewcMMljAvEO2hcrZQ/CEmK/z8agc6qxId 0zHbNYxoy6scGbXSZ8S/b/FdzWbmKog95lp1Zlt86enH9rJUPKaMNrwNZBvP+1b1golq c1a6LqtGZok7IDv7vdKLlX31gjyz5bammBkIcu4VmJRsYxhuZ16rH1uHswF5Kq/J5RrI 9+dpT6LCC0Q4tojpMOobEMkOMLKdRIikIM2tTu9xDUr86IkJF2U8s0SNjWHE8DVWttye AeSA== X-Gm-Message-State: AOJu0Yw9eOxiOOWRZSNBNRFBd/lLR8Bkhk1s8qczIs4sggUWTFxDq63O IV28/II6FxLnPpwXTonun/dM0w== X-Google-Smtp-Source: AGHT+IHe/3Q7T7mqAS39AMZy9ESnpkNFM6q37u24Z3u046keYsm8BlHmxnJkG9/CppRHC9PxpHjPRw== X-Received: by 2002:a05:6808:21a6:b0:3b9:e87b:d963 with SMTP id be38-20020a05680821a600b003b9e87bd963mr2922446oib.85.1702160903962; Sat, 09 Dec 2023 14:28:23 -0800 (PST) Received: from localhost ([2804:14d:7e39:8470:ded6:9593:9f4f:5c29]) by smtp.gmail.com with ESMTPSA id h17-20020aa786d1000000b006ce7ed5ba42sm3794269pfo.171.2023.12.09.14.28.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 09 Dec 2023 14:28:23 -0800 (PST) References: <20231122-arm64-gcs-v7-0-201c483bd775@kernel.org> <20231122-arm64-gcs-v7-25-201c483bd775@kernel.org> User-agent: mu4e 1.10.8; emacs 29.1 From: Thiago Jung Bauermann To: Mark Brown Cc: Catalin Marinas , Will Deacon , Jonathan Corbet , Andrew Morton , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Arnd Bergmann , Oleg Nesterov , Eric Biederman , Kees Cook , Shuah Khan , "Rick P. Edgecombe" , Deepak Gupta , Ard Biesheuvel , Szabolcs Nagy , "H.J. Lu" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Florian Weimer , Christian Brauner , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH v7 25/39] arm64/signal: Expose GCS state in signal frames In-reply-to: <20231122-arm64-gcs-v7-25-201c483bd775@kernel.org> Date: Sat, 09 Dec 2023 19:28:21 -0300 Message-ID: <87sf4bf1tm.fsf@linaro.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231209_142826_307273_D1F7D59B X-CRM114-Status: GOOD ( 10.85 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Mark Brown writes: > +static int preserve_gcs_context(struct gcs_context __user *ctx) > +{ > + int err = 0; > + u64 gcspr; > + > + /* > + * We will add a cap token to the frame, include it in the > + * GCSPR_EL0 we report to support stack switching via > + * sigreturn. > + */ > + gcs_preserve_current_state(); > + gcspr = current->thread.gcspr_el0; > + if (task_gcs_el0_enabled(current)) > + gcspr -= 8; > + > + __put_user_error(GCS_MAGIC, &ctx->head.magic, err); > + __put_user_error(sizeof(*ctx), &ctx->head.size, err); > + __put_user_error(gcspr, &ctx->gcspr, err); > + __put_user_error(current->thread.gcs_el0_mode, > + &ctx->features_enabled, err); Other preserve__context() functions zero the reserved fields in ctx. I suggest doing the same here. It helps with backward compatibility. > + > + return err; > +} -- Thiago _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv 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 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 54214C4167B for ; Sat, 9 Dec 2023 22:29:02 +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:Message-ID:Date: In-reply-to:Subject:Cc:To:From:References:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=6EIGGWQmEJ3xFmMjR26RZmLyY7eea4vjm18Uq1QNbow=; b=p+k/blSXsfAouhpv25wc00R7PC 3E8XEpylwxjoHA9jiugO+kK3IaCcBO5o7GFBZlyvU/fiHCStP6bnNHheaah+Ss1jU4PsYK3kfr0gP OifCodwFqXaT7BhUwn0iXcQCOOkKNrYtiWBie1oCn9G8H6mKS0ON+hJ9JcjgUagwtzG3pBq6BKeSt hFlyS9MTVdp53bUkEByVvddp4u1VHfSJ1EXkYfDdjIzFfbgnb9RvcdTYQEY4zx3ji47GZuV7DYvQp J7EwQrpI81XiZswT5fawGxHabTOA7kB8W28qZ9L89dwDlZCzD5YHz8iXvbLMkCaHAl6VO5PoKnz0z 7QTw1opQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rC5oF-000ckb-0X; Sat, 09 Dec 2023 22:28:31 +0000 Received: from mail-oi1-x22c.google.com ([2607:f8b0:4864:20::22c]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rC5oA-000chh-0q for linux-arm-kernel@lists.infradead.org; Sat, 09 Dec 2023 22:28:28 +0000 Received: by mail-oi1-x22c.google.com with SMTP id 5614622812f47-3b88f2a37deso2471252b6e.0 for ; Sat, 09 Dec 2023 14:28:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1702160904; x=1702765704; darn=lists.infradead.org; h=mime-version:message-id:date:in-reply-to:subject:cc:to:from :user-agent:references:from:to:cc:subject:date:message-id:reply-to; bh=GIZ+mcVI5qd9xzhqd2Lq/djPmsscI/1vsqmZHAfk8NA=; b=fcAyvtgr/P86KD7EgiiDUsSe6KWHQ4KjUcRbRRXa2zj8VDNy/fMl6EAm3RKHbi40Bp YvtfOopHK9uF0uUpFfNh0L47hi0UlsrUnjTPyvxeWudU0Keb3GkX5pshZmuu3ELIWfHi IhPPA9Z3CxDkocYErq6Yl2kwxItys//eielvG8TQMkWh57MnR8igcbQh1lyyiNeQyCBN wUK34T9nS9Lxzw5oRNj7YorTeHYI/45EEi4NgpwK60aNaz7CF6LyTL/ABfoU1fT9AH/s O77bBcuXg7Qrr8CN2yrSu+8ZXDgQ53X6dzM5At8jZqYlTiw2zfadtCzc1H4F9UADE5j1 jm3w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702160904; x=1702765704; h=mime-version:message-id:date:in-reply-to:subject:cc:to:from :user-agent:references:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=GIZ+mcVI5qd9xzhqd2Lq/djPmsscI/1vsqmZHAfk8NA=; b=BQXlaFrThixIv49nRit0xB4s4lXa44WFWAv3K4mAtMcX5aJSyjrnXGkrNpxcHu/ClV hEvkZjsXdxcO8by05Nnt8jkmxFQjKY7YlRRIU28roK5IkwPzf78g7m3Rs+f+rLhNl+Px HmCc/mN5Vni/AodVKh49pi4e9OdTrLIsyien2cuCrCbe/XKMMR9btOd5R+xevoQEhRSY 4hdCdpV1jnSLgwT8HkWPpMiKXafJiZZxW1GJtAnfGQ+yIZWs1M2BKYqwYThKT5MKvU0k tWj1AutDQSckHfgEeLYjeO5SLuft80K/YrHit9M4re4ExvqfcKedOV+Hh5bVbsBIU4oI PMgw== X-Gm-Message-State: AOJu0YwUoB7lDrEjuv2YRM6MctrabXmnWu1j2cxqV8g1zl5N8F7CtBXq ahRVgGgVq8+9AMnjF5e5tGXJyA== X-Google-Smtp-Source: AGHT+IHe/3Q7T7mqAS39AMZy9ESnpkNFM6q37u24Z3u046keYsm8BlHmxnJkG9/CppRHC9PxpHjPRw== X-Received: by 2002:a05:6808:21a6:b0:3b9:e87b:d963 with SMTP id be38-20020a05680821a600b003b9e87bd963mr2922446oib.85.1702160903962; Sat, 09 Dec 2023 14:28:23 -0800 (PST) Received: from localhost ([2804:14d:7e39:8470:ded6:9593:9f4f:5c29]) by smtp.gmail.com with ESMTPSA id h17-20020aa786d1000000b006ce7ed5ba42sm3794269pfo.171.2023.12.09.14.28.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 09 Dec 2023 14:28:23 -0800 (PST) References: <20231122-arm64-gcs-v7-0-201c483bd775@kernel.org> <20231122-arm64-gcs-v7-25-201c483bd775@kernel.org> User-agent: mu4e 1.10.8; emacs 29.1 From: Thiago Jung Bauermann To: Mark Brown Cc: Catalin Marinas , Will Deacon , Jonathan Corbet , Andrew Morton , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Arnd Bergmann , Oleg Nesterov , Eric Biederman , Kees Cook , Shuah Khan , "Rick P. Edgecombe" , Deepak Gupta , Ard Biesheuvel , Szabolcs Nagy , "H.J. Lu" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Florian Weimer , Christian Brauner , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH v7 25/39] arm64/signal: Expose GCS state in signal frames In-reply-to: <20231122-arm64-gcs-v7-25-201c483bd775@kernel.org> Date: Sat, 09 Dec 2023 19:28:21 -0300 Message-ID: <87sf4bf1tm.fsf@linaro.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231209_142826_307447_D55204E9 X-CRM114-Status: GOOD ( 12.27 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Mark Brown writes: > +static int preserve_gcs_context(struct gcs_context __user *ctx) > +{ > + int err = 0; > + u64 gcspr; > + > + /* > + * We will add a cap token to the frame, include it in the > + * GCSPR_EL0 we report to support stack switching via > + * sigreturn. > + */ > + gcs_preserve_current_state(); > + gcspr = current->thread.gcspr_el0; > + if (task_gcs_el0_enabled(current)) > + gcspr -= 8; > + > + __put_user_error(GCS_MAGIC, &ctx->head.magic, err); > + __put_user_error(sizeof(*ctx), &ctx->head.size, err); > + __put_user_error(gcspr, &ctx->gcspr, err); > + __put_user_error(current->thread.gcs_el0_mode, > + &ctx->features_enabled, err); Other preserve__context() functions zero the reserved fields in ctx. I suggest doing the same here. It helps with backward compatibility. > + > + return err; > +} -- Thiago _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel