From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794225928; b=TGqN3oroAdIE9z/tBHUrreLjTGy5wT/kmXKlm6UQq28whOTegUUrs/BdGSv6lfpx6I7w 1u2sHHfMQln55JTpnCSj6dhGq+7c7/FISyxbyzB0zPG2GUl2R4z8CNeBC4S33ftVI5TbP +IQMVEWrGpOSmLvwYCxFMOClS9SlXTvwiOXo3JnOHF8R00TqKmHbe81im1rgUl1kTML8s 9L4hJH/NRNrduvrHGccsRyGQ2a53uQcigsRfJKqUNyC5pati8yTrttvyyxKd1YYOTKFe4 c4y36w8HcuDVj0h0u0NJuxlO//8X4ug1ukqxT6R9HTz+crdwCH26mbiXocLDpVGKirg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794225928; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=bP0SvI1SyNFWGaznG9wghum5HnnqOxchfJ6Ki1mewRQ=; b=KdmiDG/kEM2XLOwOlHbWHc7SshZM14Q6h3qanI2Rl8FFN5aFvNrWrXoB+bOtpI6GSy+i 4V5ZncKlSyXJGWT7o8VJPVWjfgudsUPMAOjmZ31Tv9tMzmx3Q//Rtgxy6/2MBbhQxiGJ7 CmB63uZlj0W4eYIyCIUV3Q91Zgu2ge9GcW6GuJKSzRCLaACjhpsdQPlqGLPpY7cPUfASs 5xXV717jSV33IOcawVs19auDtLxfy+paAuGjrGuy3O0Tkhl+r6N5L2Hw6cyKxPMmyUrxN PFlQOpHGSee6Ct5FkKCiE5JWlsUVqDSsTQTXY6T/NTlmBRXlniPgEY8mkg7rTMtd0Bg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Wi70OnYd; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EA062606A32A for ; Mon, 9 Nov 2026 12:05:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Wi70OnYd Received: by smtp.kernel.org (Postfix) with ESMTPSA id A39FC1F008A2; Mon, 9 Nov 2026 12:05:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794225927; bh=bP0SvI1SyNFWGaznG9wghum5HnnqOxchfJ6Ki1mewRQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Wi70OnYdXmU/O5nlE/GYtPpXZc8dZ424yjRjXLwEb6eTHY1K8E+36UyZSllQUnGCB WQkz5zKyd6wqkCbfXFNIXaR1/R90WpjbgNB1/01+YQkDQ2ANmTwfMH+5ifbsMrEb7q GkfDMhHXHhrpxrMVXW/sfzie1Hnru04kpBlgkiSA/Hs4JrAzE+/VqHiCLS+/RKB68+ ZEfKMa+J6A2lPZa4UFALIHcd8Q5uR+b9B5Ojdt5CbuDb+VYE0CNOYysFUzkPlusF1Q hJ1tcHpm+kPyQtPHtcNolz6olZ7kUUl4DkKPFuTDs01ql81IZCQfXaj/i0bXkxpndd 3/uFwMb3OWb3g== From: Jisheng Zhang To: Catalin Marinas , Will Deacon , Mark Rutland , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Tejun Heo , Dennis Zhou , Christoph Lameter Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, linux-mm@kvack.org Subject: [PATCH v2 4/6] arm64: stacktrace: Always inline internal stack boundary helpers Date: Mon, 9 Nov 2026 19:44:57 +0800 Message-ID: <20261109114500.20298-5-jszhang@kernel.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20261109114500.20298-1-jszhang@kernel.org> References: <20261109114500.20298-1-jszhang@kernel.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The noinstr stack walkers reach the stack boundary and frame-record helpers through an __always_inline call chain. However, these shared helpers do not themselves guarantee inlining. With CONFIG_CC_OPTIMIZE_FOR_SIZE=y, GCC emitted several stack information helpers and unwind_find_stack() out of line in .text. Mark the shared stack boundary and frame-record helpers __always_inline to keep their instructions in the non-instrumentable walkers Signed-off-by: Jisheng Zhang Assisted-by: LLM --- arch/arm64/include/asm/stacktrace.h | 16 ++++++++-------- arch/arm64/include/asm/stacktrace/common.h | 12 ++++++------ 2 files changed, 14 insertions(+), 14 deletions(-) diff --git a/arch/arm64/include/asm/stacktrace.h b/arch/arm64/include/asm/stacktrace.h index 6d3280932bf5..b370c0e1e337 100644 --- a/arch/arm64/include/asm/stacktrace.h +++ b/arch/arm64/include/asm/stacktrace.h @@ -22,7 +22,7 @@ extern void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, DECLARE_PER_CPU(unsigned long *, irq_stack_ptr); -static inline struct stack_info stackinfo_get_irq(void) +static __always_inline struct stack_info stackinfo_get_irq(void) { unsigned long low = (unsigned long)raw_cpu_read(irq_stack_ptr); unsigned long high = low + IRQ_STACK_SIZE; @@ -33,13 +33,13 @@ static inline struct stack_info stackinfo_get_irq(void) }; } -static inline bool on_irq_stack(unsigned long sp, unsigned long size) +static __always_inline bool on_irq_stack(unsigned long sp, unsigned long size) { struct stack_info info = stackinfo_get_irq(); return stackinfo_on_stack(&info, sp, size); } -static inline struct stack_info stackinfo_get_task(const struct task_struct *tsk) +static __always_inline struct stack_info stackinfo_get_task(const struct task_struct *tsk) { unsigned long low = (unsigned long)task_stack_page(tsk); unsigned long high = low + THREAD_SIZE; @@ -50,7 +50,7 @@ static inline struct stack_info stackinfo_get_task(const struct task_struct *tsk }; } -static inline bool on_task_stack(const struct task_struct *tsk, +static __always_inline bool on_task_stack(const struct task_struct *tsk, unsigned long sp, unsigned long size) { struct stack_info info = stackinfo_get_task(tsk); @@ -61,7 +61,7 @@ static inline bool on_task_stack(const struct task_struct *tsk, DECLARE_PER_CPU(unsigned long [OVERFLOW_STACK_SIZE/sizeof(long)], overflow_stack); -static inline struct stack_info stackinfo_get_overflow(void) +static __always_inline struct stack_info stackinfo_get_overflow(void) { unsigned long low = (unsigned long)raw_cpu_ptr(overflow_stack); unsigned long high = low + OVERFLOW_STACK_SIZE; @@ -76,7 +76,7 @@ static inline struct stack_info stackinfo_get_overflow(void) DECLARE_PER_CPU(unsigned long *, sdei_stack_normal_ptr); DECLARE_PER_CPU(unsigned long *, sdei_stack_critical_ptr); -static inline struct stack_info stackinfo_get_sdei_normal(void) +static __always_inline struct stack_info stackinfo_get_sdei_normal(void) { unsigned long low = (unsigned long)raw_cpu_read(sdei_stack_normal_ptr); unsigned long high = low + SDEI_STACK_SIZE; @@ -87,7 +87,7 @@ static inline struct stack_info stackinfo_get_sdei_normal(void) }; } -static inline struct stack_info stackinfo_get_sdei_critical(void) +static __always_inline struct stack_info stackinfo_get_sdei_critical(void) { unsigned long low = (unsigned long)raw_cpu_read(sdei_stack_critical_ptr); unsigned long high = low + SDEI_STACK_SIZE; @@ -105,7 +105,7 @@ static inline struct stack_info stackinfo_get_sdei_critical(void) #ifdef CONFIG_EFI extern u64 *efi_rt_stack_top; -static inline struct stack_info stackinfo_get_efi(void) +static __always_inline struct stack_info stackinfo_get_efi(void) { unsigned long high = (u64)efi_rt_stack_top; unsigned long low = high - THREAD_SIZE; diff --git a/arch/arm64/include/asm/stacktrace/common.h b/arch/arm64/include/asm/stacktrace/common.h index 821a8fdd31af..7c502ae276b9 100644 --- a/arch/arm64/include/asm/stacktrace/common.h +++ b/arch/arm64/include/asm/stacktrace/common.h @@ -35,7 +35,7 @@ struct unwind_state { int nr_stacks; }; -static inline struct stack_info stackinfo_get_unknown(void) +static __always_inline struct stack_info stackinfo_get_unknown(void) { return (struct stack_info) { .low = 0, @@ -43,7 +43,7 @@ static inline struct stack_info stackinfo_get_unknown(void) }; } -static inline bool stackinfo_on_stack(const struct stack_info *info, +static __always_inline bool stackinfo_on_stack(const struct stack_info *info, unsigned long sp, unsigned long size) { if (!info->low) @@ -55,7 +55,7 @@ static inline bool stackinfo_on_stack(const struct stack_info *info, return true; } -static inline void unwind_init_common(struct unwind_state *state) +static __always_inline void unwind_init_common(struct unwind_state *state) { state->stack = stackinfo_get_unknown(); } @@ -70,7 +70,7 @@ static inline void unwind_init_common(struct unwind_state *state) * * Return: a pointer to the relevant stack_info if found; NULL otherwise. */ -static struct stack_info *unwind_find_stack(struct unwind_state *state, +static __always_inline struct stack_info *unwind_find_stack(struct unwind_state *state, unsigned long sp, unsigned long size) { @@ -99,7 +99,7 @@ static struct stack_info *unwind_find_stack(struct unwind_state *state, * * Return: 0 upon success, an error code otherwise. */ -static inline void unwind_consume_stack(struct unwind_state *state, +static __always_inline void unwind_consume_stack(struct unwind_state *state, struct stack_info *info, unsigned long sp, unsigned long size) @@ -142,7 +142,7 @@ static inline void unwind_consume_stack(struct unwind_state *state, * * Return: 0 upon success, an error code otherwise. */ -static inline int +static __always_inline int unwind_next_frame_record(struct unwind_state *state) { struct stack_info *info; -- 2.55.0