From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7D1242F3C1D; Tue, 2 Sep 2025 10:22:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756808550; cv=none; b=kitUFtfJaOeBE6pYOn8kmrUZlnxxFw0jGGpJWDu5cQvdLEtevAz9FMHsSnzhIRBa1A/9+wAYVChjWjqOuaepBO/VxpqQnuaoGJhBifq60xrVAwFTFwqrzUud9FDB24643CdBVGS9vPuU50KmAqZDKaWtqLX735GyjO8DzQtlL7E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756808550; c=relaxed/simple; bh=sCkuhZhQLgVA+X2B9E/24D8lf8QLxbBNxj1NjjW+v04=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=BYBl/nPWjLhakEyacowuIUxB9XOWrlHMygbAAGg8ppVDCdQpcsClPqf7BiR3wiWcA6V8uGYwY4KoW7BJ92mtyHrwj3I/F9SHj3Y0AC1EFGaOcZ6EFFN207xxIgi1Shp7CH5k+Hd5qMSvGTd+kXab/4jdGV9PkQul7ScoiTJKdbI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=aRyd9SBM; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="aRyd9SBM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D5EEFC4CEF5; Tue, 2 Sep 2025 10:22:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756808549; bh=sCkuhZhQLgVA+X2B9E/24D8lf8QLxbBNxj1NjjW+v04=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=aRyd9SBMcjdV4og1ltHdfkn4DvlbCPrVqh/uF73gIB2HTJBwdumz0/cvg9M+cgeQU Sg3VBET4Px11382wau/TU1802KVoNRk8fJ9Vce6Umyt34VB2L1O7UH0mX106oUlkEH 6ZYfZZbbnrIhNcBvwU2z7XqHW9/58gCnS+2qlFCs0cYPW/6mc39lkSE9AdMWthTEJs EBsDBrCTXDNb8Ox6aejU9FoFV0aTOxMQa1hlEWUvkr+QR/kC5m7LUB3x3wzK1Ue99j LdWkasRA6FRxglQE7qaevZI7u1Kw/iVlbWcucXNWPLNJpFjtxNsl4qYLCuSfm/v+V1 NDi1I8pyQ3+JQ== From: Mark Brown Date: Tue, 02 Sep 2025 11:21:45 +0100 Subject: [PATCH v20 1/8] arm64/gcs: Return a success value from gcs_alloc_thread_stack() Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20250902-clone3-shadow-stack-v20-1-4d9fff1c53e7@kernel.org> References: <20250902-clone3-shadow-stack-v20-0-4d9fff1c53e7@kernel.org> In-Reply-To: <20250902-clone3-shadow-stack-v20-0-4d9fff1c53e7@kernel.org> To: "Rick P. Edgecombe" , Deepak Gupta , Szabolcs Nagy , "H.J. Lu" , Florian Weimer , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Christian Brauner , Shuah Khan Cc: linux-kernel@vger.kernel.org, Catalin Marinas , Will Deacon , jannh@google.com, bsegall@google.com, Andrew Morton , Yury Khrustalev , Wilco Dijkstra , linux-kselftest@vger.kernel.org, linux-api@vger.kernel.org, Mark Brown , Kees Cook X-Mailer: b4 0.15-dev-cff91 X-Developer-Signature: v=1; a=openpgp-sha256; l=3726; i=broonie@kernel.org; h=from:subject:message-id; bh=sCkuhZhQLgVA+X2B9E/24D8lf8QLxbBNxj1NjjW+v04=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBotsVTvFrPQ/44ijTMy4nQPjMRqOSQw1Ozc9WMy spgEEVX9TaJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCaLbFUwAKCRAk1otyXVSH 0MisB/93EeWirSq+14A3iPUXfZq1WyF3Btt+T07QHDPQofqiG3RFcIdqnv/ZfqiHAj/WHUb09YH kYNfRoD5dE549tpy1I0AAz3gMWa90j94kzf42Cxa+NfBg/rY1PzWRQEaQNct/fWmaygvmNfrGpB 3s4I2w8HZ/uTsSE1bAeb2bn3yEifufSGujnAdcK3DPBGQNDpSojsnKfZJj/ZxzYEbObngqlHWa8 YdjGdBcYtZ8NPqMPKMjjWFL4VNz16v0AR5UYU8VHvujGyGphDDE7dRjF/ycKMCcAMxkNUVgnmkz K+XrHO3ICgAA0WO2/DqV7RgTdAFfMwGq3V9TaWGP3GLXJLNd X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Currently as a result of templating from x86 code gcs_alloc_thread_stack() returns a pointer as an unsigned int however on arm64 we don't actually use this pointer value as anything other than a pass/fail flag. Simplify the interface to just return an int with 0 on success and a negative error code on failure. Acked-by: Deepak Gupta Reviewed-by: Catalin Marinas Signed-off-by: Mark Brown --- arch/arm64/include/asm/gcs.h | 8 ++++---- arch/arm64/kernel/process.c | 8 ++++---- arch/arm64/mm/gcs.c | 8 ++++---- 3 files changed, 12 insertions(+), 12 deletions(-) diff --git a/arch/arm64/include/asm/gcs.h b/arch/arm64/include/asm/gcs.h index 5bc432234d3a..b4bbec9382a1 100644 --- a/arch/arm64/include/asm/gcs.h +++ b/arch/arm64/include/asm/gcs.h @@ -64,8 +64,8 @@ static inline bool task_gcs_el0_enabled(struct task_struct *task) void gcs_set_el0_mode(struct task_struct *task); void gcs_free(struct task_struct *task); void gcs_preserve_current_state(void); -unsigned long gcs_alloc_thread_stack(struct task_struct *tsk, - const struct kernel_clone_args *args); +int gcs_alloc_thread_stack(struct task_struct *tsk, + const struct kernel_clone_args *args); static inline int gcs_check_locked(struct task_struct *task, unsigned long new_val) @@ -91,8 +91,8 @@ static inline bool task_gcs_el0_enabled(struct task_struct *task) static inline void gcs_set_el0_mode(struct task_struct *task) { } static inline void gcs_free(struct task_struct *task) { } static inline void gcs_preserve_current_state(void) { } -static inline unsigned long gcs_alloc_thread_stack(struct task_struct *tsk, - const struct kernel_clone_args *args) +static inline int gcs_alloc_thread_stack(struct task_struct *tsk, + const struct kernel_clone_args *args) { return -ENOTSUPP; } diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 96482a1412c6..f0b1bea9c873 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -299,7 +299,7 @@ static void flush_gcs(void) static int copy_thread_gcs(struct task_struct *p, const struct kernel_clone_args *args) { - unsigned long gcs; + int ret; if (!system_supports_gcs()) return 0; @@ -310,9 +310,9 @@ static int copy_thread_gcs(struct task_struct *p, p->thread.gcs_el0_mode = current->thread.gcs_el0_mode; p->thread.gcs_el0_locked = current->thread.gcs_el0_locked; - gcs = gcs_alloc_thread_stack(p, args); - if (IS_ERR_VALUE(gcs)) - return PTR_ERR((void *)gcs); + ret = gcs_alloc_thread_stack(p, args); + if (ret != 0) + return ret; return 0; } diff --git a/arch/arm64/mm/gcs.c b/arch/arm64/mm/gcs.c index 6e93f78de79b..3abcbf9adb5c 100644 --- a/arch/arm64/mm/gcs.c +++ b/arch/arm64/mm/gcs.c @@ -38,8 +38,8 @@ static unsigned long gcs_size(unsigned long size) return max(PAGE_SIZE, size); } -unsigned long gcs_alloc_thread_stack(struct task_struct *tsk, - const struct kernel_clone_args *args) +int gcs_alloc_thread_stack(struct task_struct *tsk, + const struct kernel_clone_args *args) { unsigned long addr, size; @@ -59,13 +59,13 @@ unsigned long gcs_alloc_thread_stack(struct task_struct *tsk, size = gcs_size(size); addr = alloc_gcs(0, size); if (IS_ERR_VALUE(addr)) - return addr; + return PTR_ERR((void *)addr); tsk->thread.gcs_base = addr; tsk->thread.gcs_size = size; tsk->thread.gcspr_el0 = addr + size - sizeof(u64); - return addr; + return 0; } SYSCALL_DEFINE3(map_shadow_stack, unsigned long, addr, unsigned long, size, unsigned int, flags) -- 2.39.5