From patchwork Thu Nov 3 07:50:40 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guo Ren X-Patchwork-Id: 13029661 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 B1F0DC433FE for ; Thu, 3 Nov 2022 07:52:32 +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:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=vHkayffPHTb24NG6g0ZugExxZfJG32SjSw5GuOFd7x0=; b=MwZAU3OOjA8fXF +lJY4Xu21yTzvkFE+ki2v7HdTPuLUvOMQq8kI6jJm+P/TgUdhQzitVzF8bt3zFlfxaUM4IXFzf14A SQM9tZlKkieeJOVjjfEoa7dAEfjwJKNfuV9v2skqXegnEI1uyALejDvV6RuvTamH6WoTSLeCFWl4l k+9bdN0gy5nup+AkLfYrLrImKWE0GVQmFaxjEjmcEPzzicYb/2d5Wq8gs+pimF60hFHaci7IBnseA y3VjLHGI5E5bawIvm4kUUPUjsq5oER1Uo54Res/q9g2ARqfeu6dIpvhldpG361nTQCu9GNkCDT5+w R2noxOYTE/VaaNgHWQug==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oqV1T-00GW4Q-V8; Thu, 03 Nov 2022 07:52:23 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oqV1Q-00GW2G-NI for linux-riscv@lists.infradead.org; Thu, 03 Nov 2022 07:52:22 +0000 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 dfw.source.kernel.org (Postfix) with ESMTPS id 4984D61D97; Thu, 3 Nov 2022 07:52:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B23A1C433D7; Thu, 3 Nov 2022 07:52:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1667461939; bh=GoFNCdcc0BfY8mmB/HPBR5Zbdk7Ko/l4uIuW4tV4Ru8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=T40LM6eFz5lvZI8l3p6OESbOXwhgDg9d2brW+qdtKUtDPS5GOmkA/nFK8/QclPAQq OCKAJEIToIuldSXh/sLOfQVBilQj9ju3qnKJ+7NMxnRkECcCbdr35B3RxSZvMVOaZX eiymRIvPsD7Gn+S8bow6C2Y0nzpu/cDNjFoS1S7vay5zRbB5HI8zUjAstAHGgloQqC Uh6ye2TDO8SVV14uUXq0044jdEq+ItLz8rLxjKa11YoWpdeYQ4BI2UDfEow8by23xP I9z2XlMGkZIE4jOhCLLNP+03/CCfGM5FJEjdvGyH8yzf3zh/JaEhEsFizlszjjDsPC /Tj76F/RF/2FA== From: guoren@kernel.org To: arnd@arndb.de, guoren@kernel.org, palmer@rivosinc.com, tglx@linutronix.de, peterz@infradead.org, luto@kernel.org, conor.dooley@microchip.com, heiko@sntech.de, jszhang@kernel.org, lazyparser@gmail.com, falcon@tinylab.org, chenhuacai@kernel.org, apatel@ventanamicro.com, atishp@atishpatra.org, palmer@dabbelt.com, paul.walmsley@sifive.com, mark.rutland@arm.com, zouyipeng@huawei.com, bigeasy@linutronix.de, David.Laight@aculab.com, chenzhongjin@huawei.com, greentime.hu@sifive.com, andy.chiu@sifive.com Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Guo Ren Subject: [PATCH -next V8 07/14] riscv: Support HAVE_IRQ_EXIT_ON_IRQ_STACK Date: Thu, 3 Nov 2022 03:50:40 -0400 Message-Id: <20221103075047.1634923-8-guoren@kernel.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20221103075047.1634923-1-guoren@kernel.org> References: <20221103075047.1634923-1-guoren@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221103_005221_023353_CD095417 X-CRM114-Status: GOOD ( 19.09 ) 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: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Guo Ren Add independent irq stacks for percpu to prevent kernel stack overflows. It is also compatible with VMAP_STACK by implementing arch_alloc_vmap_stack. Many architectures have supported HAVE_IRQ_EXIT_ON_IRQ_STACK, riscv should follow up. Signed-off-by: Guo Ren Signed-off-by: Guo Ren --- arch/riscv/Kconfig | 8 ++++ arch/riscv/include/asm/thread_info.h | 2 + arch/riscv/include/asm/vmap_stack.h | 28 ++++++++++++ arch/riscv/kernel/irq.c | 66 +++++++++++++++++++++++++++- 4 files changed, 102 insertions(+), 2 deletions(-) create mode 100644 arch/riscv/include/asm/vmap_stack.h diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 6cd3b1d1aeb2..2653a381cc62 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -445,6 +445,14 @@ config FPU If you don't know what to do here, say Y. +config IRQ_STACKS + bool "Independent irq stacks" if EXPERT + default y + select HAVE_IRQ_EXIT_ON_IRQ_STACK + help + Add independent irq stacks for percpu to prevent kernel stack overflows. + We may save some memory footprint by disabling IRQ_STACKS. + endmenu # "Platform type" menu "Kernel features" diff --git a/arch/riscv/include/asm/thread_info.h b/arch/riscv/include/asm/thread_info.h index 7de4fb96f0b5..043da8ccc7e6 100644 --- a/arch/riscv/include/asm/thread_info.h +++ b/arch/riscv/include/asm/thread_info.h @@ -40,6 +40,8 @@ #define OVERFLOW_STACK_SIZE SZ_4K #define SHADOW_OVERFLOW_STACK_SIZE (1024) +#define IRQ_STACK_SIZE THREAD_SIZE + #ifndef __ASSEMBLY__ extern long shadow_stack[SHADOW_OVERFLOW_STACK_SIZE / sizeof(long)]; diff --git a/arch/riscv/include/asm/vmap_stack.h b/arch/riscv/include/asm/vmap_stack.h new file mode 100644 index 000000000000..3fbf481abf4f --- /dev/null +++ b/arch/riscv/include/asm/vmap_stack.h @@ -0,0 +1,28 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +// Copied from arch/arm64/include/asm/vmap_stack.h. +#ifndef _ASM_RISCV_VMAP_STACK_H +#define _ASM_RISCV_VMAP_STACK_H + +#include +#include +#include +#include +#include +#include + +/* + * To ensure that VMAP'd stack overflow detection works correctly, all VMAP'd + * stacks need to have the same alignment. + */ +static inline unsigned long *arch_alloc_vmap_stack(size_t stack_size, int node) +{ + void *p; + + BUILD_BUG_ON(!IS_ENABLED(CONFIG_VMAP_STACK)); + + p = __vmalloc_node(stack_size, THREAD_ALIGN, THREADINFO_GFP, node, + __builtin_return_address(0)); + return kasan_reset_tag(p); +} + +#endif /* _ASM_RISCV_VMAP_STACK_H */ diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c index 24c2e1bd756a..5d77f692b198 100644 --- a/arch/riscv/kernel/irq.c +++ b/arch/riscv/kernel/irq.c @@ -10,6 +10,37 @@ #include #include #include +#include + +#ifdef CONFIG_IRQ_STACKS +static DEFINE_PER_CPU(ulong *, irq_stack_ptr); + +#ifdef CONFIG_VMAP_STACK +static void init_irq_stacks(void) +{ + int cpu; + ulong *p; + + for_each_possible_cpu(cpu) { + p = arch_alloc_vmap_stack(IRQ_STACK_SIZE, cpu_to_node(cpu)); + per_cpu(irq_stack_ptr, cpu) = p; + } +} +#else +/* irq stack only needs to be 16 byte aligned - not IRQ_STACK_SIZE aligned. */ +DEFINE_PER_CPU_ALIGNED(ulong [IRQ_STACK_SIZE/sizeof(ulong)], irq_stack); + +static void init_irq_stacks(void) +{ + int cpu; + + for_each_possible_cpu(cpu) + per_cpu(irq_stack_ptr, cpu) = per_cpu(irq_stack, cpu); +} +#endif /* CONFIG_VMAP_STACK */ +#else +static void init_irq_stacks(void) {} +#endif /* CONFIG_IRQ_STACKS */ int arch_show_interrupts(struct seq_file *p, int prec) { @@ -19,21 +50,52 @@ int arch_show_interrupts(struct seq_file *p, int prec) void __init init_IRQ(void) { + init_irq_stacks(); irqchip_init(); if (!handle_arch_irq) panic("No interrupt controller found."); } -asmlinkage void noinstr do_riscv_irq(struct pt_regs *regs) +static void noinstr handle_riscv_irq(struct pt_regs *regs) { struct pt_regs *old_regs; - irqentry_state_t state = irqentry_enter(regs); irq_enter_rcu(); old_regs = set_irq_regs(regs); handle_arch_irq(regs); set_irq_regs(old_regs); irq_exit_rcu(); +} + +asmlinkage void noinstr do_riscv_irq(struct pt_regs *regs) +{ + irqentry_state_t state = irqentry_enter(regs); +#ifdef CONFIG_IRQ_STACKS + if (on_thread_stack()) { + ulong *sp = per_cpu(irq_stack_ptr, smp_processor_id()) + + IRQ_STACK_SIZE/sizeof(ulong); + __asm__ __volatile( + "addi sp, sp, -"RISCV_SZPTR "\n" + REG_S" ra, (sp) \n" + "addi sp, sp, -"RISCV_SZPTR "\n" + REG_S" s0, (sp) \n" + "addi s0, sp, 2*"RISCV_SZPTR "\n" + "move sp, %[sp] \n" + "move a0, %[regs] \n" + "call handle_riscv_irq \n" + "addi sp, s0, -2*"RISCV_SZPTR"\n" + REG_L" s0, (sp) \n" + "addi sp, sp, "RISCV_SZPTR "\n" + REG_L" ra, (sp) \n" + "addi sp, sp, "RISCV_SZPTR "\n" + : + : [sp] "r" (sp), [regs] "r" (regs) + : "a0", "a1", "a2", "a3", "a4", "a5", "a6", "a7", + "t0", "t1", "t2", "t3", "t4", "t5", "t6", + "memory"); + } else +#endif + handle_riscv_irq(regs); irqentry_exit(regs, state); }