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author | Catalin Marinas <catalin.marinas@arm.com> | 2020-12-09 21:04:48 +0300 |
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committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-12-09 21:04:48 +0300 |
commit | d45056ad739be9d6a267fe23af9923fe50a0d575 (patch) | |
tree | ca6a43b0d498242857bf0a94b952345e01933551 /arch/arm64 | |
parent | d8602f8bf3b2329c366dd37fc6adf573ba2c4784 (diff) | |
parent | eec3bf6861a8703ab63992578b1776353c5ac2a1 (diff) | |
download | linux-d45056ad739be9d6a267fe23af9923fe50a0d575.tar.xz |
Merge remote-tracking branch 'arm64/for-next/scs' into for-next/core
* arm64/for-next/scs:
arm64: sdei: Push IS_ENABLED() checks down to callee functions
arm64: scs: use vmapped IRQ and SDEI shadow stacks
scs: switch to vmapped shadow stacks
Diffstat (limited to 'arch/arm64')
-rw-r--r-- | arch/arm64/kernel/Makefile | 1 | ||||
-rw-r--r-- | arch/arm64/kernel/entry.S | 6 | ||||
-rw-r--r-- | arch/arm64/kernel/irq.c | 21 | ||||
-rw-r--r-- | arch/arm64/kernel/scs.c | 16 | ||||
-rw-r--r-- | arch/arm64/kernel/sdei.c | 86 |
5 files changed, 105 insertions, 25 deletions
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index bbaf0bc4ad60..86364ab6f13f 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -58,7 +58,6 @@ obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_CRASH_CORE) += crash_core.o obj-$(CONFIG_ARM_SDE_INTERFACE) += sdei.o obj-$(CONFIG_ARM64_PTR_AUTH) += pointer_auth.o -obj-$(CONFIG_SHADOW_CALL_STACK) += scs.o obj-$(CONFIG_ARM64_MTE) += mte.o obj-y += vdso/ probes/ diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 4742a0f3d11a..d61043a00679 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -429,7 +429,7 @@ SYM_CODE_END(__swpan_exit_el0) #ifdef CONFIG_SHADOW_CALL_STACK /* also switch to the irq shadow stack */ - adr_this_cpu scs_sp, irq_shadow_call_stack, x26 + ldr_this_cpu scs_sp, irq_shadow_call_stack_ptr, x26 #endif 9998: @@ -1086,9 +1086,9 @@ SYM_CODE_START(__sdei_asm_handler) #ifdef CONFIG_SHADOW_CALL_STACK /* Use a separate shadow call stack for normal and critical events */ cbnz w4, 3f - adr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_normal, tmp=x6 + ldr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_normal_ptr, tmp=x6 b 4f -3: adr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_critical, tmp=x6 +3: ldr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_critical_ptr, tmp=x6 4: #endif diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c index 9cf2fb87584a..ac54c21140d4 100644 --- a/arch/arm64/kernel/irq.c +++ b/arch/arm64/kernel/irq.c @@ -17,6 +17,7 @@ #include <linux/init.h> #include <linux/irqchip.h> #include <linux/kprobes.h> +#include <linux/scs.h> #include <linux/seq_file.h> #include <linux/vmalloc.h> #include <asm/daifflags.h> @@ -27,6 +28,25 @@ DEFINE_PER_CPU(struct nmi_ctx, nmi_contexts); DEFINE_PER_CPU(unsigned long *, irq_stack_ptr); + +DECLARE_PER_CPU(unsigned long *, irq_shadow_call_stack_ptr); + +#ifdef CONFIG_SHADOW_CALL_STACK +DEFINE_PER_CPU(unsigned long *, irq_shadow_call_stack_ptr); +#endif + +static void init_irq_scs(void) +{ + int cpu; + + if (!IS_ENABLED(CONFIG_SHADOW_CALL_STACK)) + return; + + for_each_possible_cpu(cpu) + per_cpu(irq_shadow_call_stack_ptr, cpu) = + scs_alloc(cpu_to_node(cpu)); +} + #ifdef CONFIG_VMAP_STACK static void init_irq_stacks(void) { @@ -54,6 +74,7 @@ static void init_irq_stacks(void) void __init init_IRQ(void) { init_irq_stacks(); + init_irq_scs(); irqchip_init(); if (!handle_arch_irq) panic("No interrupt controller found."); diff --git a/arch/arm64/kernel/scs.c b/arch/arm64/kernel/scs.c deleted file mode 100644 index e8f7ff45dd8f..000000000000 --- a/arch/arm64/kernel/scs.c +++ /dev/null @@ -1,16 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Shadow Call Stack support. - * - * Copyright (C) 2019 Google LLC - */ - -#include <linux/percpu.h> -#include <linux/scs.h> - -DEFINE_SCS(irq_shadow_call_stack); - -#ifdef CONFIG_ARM_SDE_INTERFACE -DEFINE_SCS(sdei_shadow_call_stack_normal); -DEFINE_SCS(sdei_shadow_call_stack_critical); -#endif diff --git a/arch/arm64/kernel/sdei.c b/arch/arm64/kernel/sdei.c index e04b3e90c003..35298f4e3faf 100644 --- a/arch/arm64/kernel/sdei.c +++ b/arch/arm64/kernel/sdei.c @@ -7,6 +7,7 @@ #include <linux/hardirq.h> #include <linux/irqflags.h> #include <linux/sched/task_stack.h> +#include <linux/scs.h> #include <linux/uaccess.h> #include <asm/alternative.h> @@ -37,6 +38,14 @@ DEFINE_PER_CPU(unsigned long *, sdei_stack_normal_ptr); DEFINE_PER_CPU(unsigned long *, sdei_stack_critical_ptr); #endif +DECLARE_PER_CPU(unsigned long *, sdei_shadow_call_stack_normal_ptr); +DECLARE_PER_CPU(unsigned long *, sdei_shadow_call_stack_critical_ptr); + +#ifdef CONFIG_SHADOW_CALL_STACK +DEFINE_PER_CPU(unsigned long *, sdei_shadow_call_stack_normal_ptr); +DEFINE_PER_CPU(unsigned long *, sdei_shadow_call_stack_critical_ptr); +#endif + static void _free_sdei_stack(unsigned long * __percpu *ptr, int cpu) { unsigned long *p; @@ -52,6 +61,9 @@ static void free_sdei_stacks(void) { int cpu; + if (!IS_ENABLED(CONFIG_VMAP_STACK)) + return; + for_each_possible_cpu(cpu) { _free_sdei_stack(&sdei_stack_normal_ptr, cpu); _free_sdei_stack(&sdei_stack_critical_ptr, cpu); @@ -75,6 +87,9 @@ static int init_sdei_stacks(void) int cpu; int err = 0; + if (!IS_ENABLED(CONFIG_VMAP_STACK)) + return 0; + for_each_possible_cpu(cpu) { err = _init_sdei_stack(&sdei_stack_normal_ptr, cpu); if (err) @@ -90,6 +105,62 @@ static int init_sdei_stacks(void) return err; } +static void _free_sdei_scs(unsigned long * __percpu *ptr, int cpu) +{ + void *s; + + s = per_cpu(*ptr, cpu); + if (s) { + per_cpu(*ptr, cpu) = NULL; + scs_free(s); + } +} + +static void free_sdei_scs(void) +{ + int cpu; + + for_each_possible_cpu(cpu) { + _free_sdei_scs(&sdei_shadow_call_stack_normal_ptr, cpu); + _free_sdei_scs(&sdei_shadow_call_stack_critical_ptr, cpu); + } +} + +static int _init_sdei_scs(unsigned long * __percpu *ptr, int cpu) +{ + void *s; + + s = scs_alloc(cpu_to_node(cpu)); + if (!s) + return -ENOMEM; + per_cpu(*ptr, cpu) = s; + + return 0; +} + +static int init_sdei_scs(void) +{ + int cpu; + int err = 0; + + if (!IS_ENABLED(CONFIG_SHADOW_CALL_STACK)) + return 0; + + for_each_possible_cpu(cpu) { + err = _init_sdei_scs(&sdei_shadow_call_stack_normal_ptr, cpu); + if (err) + break; + err = _init_sdei_scs(&sdei_shadow_call_stack_critical_ptr, cpu); + if (err) + break; + } + + if (err) + free_sdei_scs(); + + return err; +} + static bool on_sdei_normal_stack(unsigned long sp, struct stack_info *info) { unsigned long low = (unsigned long)raw_cpu_read(sdei_stack_normal_ptr); @@ -130,13 +201,14 @@ unsigned long sdei_arch_get_entry_point(int conduit) */ if (is_hyp_mode_available() && !is_kernel_in_hyp_mode()) { pr_err("Not supported on this hardware/boot configuration\n"); - return 0; + goto out_err; } - if (IS_ENABLED(CONFIG_VMAP_STACK)) { - if (init_sdei_stacks()) - return 0; - } + if (init_sdei_stacks()) + goto out_err; + + if (init_sdei_scs()) + goto out_err_free_stacks; sdei_exit_mode = (conduit == SMCCC_CONDUIT_HVC) ? SDEI_EXIT_HVC : SDEI_EXIT_SMC; @@ -151,6 +223,10 @@ unsigned long sdei_arch_get_entry_point(int conduit) #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */ return (unsigned long)__sdei_asm_handler; +out_err_free_stacks: + free_sdei_stacks(); +out_err: + return 0; } /* |