diff options
Diffstat (limited to 'arch/x86/kernel')
42 files changed, 664 insertions, 589 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 0503f5bfb18d..45257cf84370 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -125,6 +125,12 @@ obj-$(CONFIG_EFI) += sysfb_efi.o obj-$(CONFIG_PERF_EVENTS) += perf_regs.o obj-$(CONFIG_TRACING) += tracepoint.o +ifdef CONFIG_FRAME_POINTER +obj-y += unwind_frame.o +else +obj-y += unwind_guess.o +endif + ### # 64 bit specific files ifeq ($(CONFIG_X86_64),y) diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c index adb3eaf8fe2a..48587335ede8 100644 --- a/arch/x86/kernel/acpi/sleep.c +++ b/arch/x86/kernel/acpi/sleep.c @@ -99,7 +99,7 @@ int x86_acpi_suspend_lowlevel(void) saved_magic = 0x12345678; #else /* CONFIG_64BIT */ #ifdef CONFIG_SMP - stack_start = (unsigned long)temp_stack + sizeof(temp_stack); + initial_stack = (unsigned long)temp_stack + sizeof(temp_stack); early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(smp_processor_id()); initial_gs = per_cpu_offset(smp_processor_id()); diff --git a/arch/x86/kernel/apic/apic_flat_64.c b/arch/x86/kernel/apic/apic_flat_64.c index 5b2ae106bd4a..8862da76ef6f 100644 --- a/arch/x86/kernel/apic/apic_flat_64.c +++ b/arch/x86/kernel/apic/apic_flat_64.c @@ -25,7 +25,7 @@ static struct apic apic_physflat; static struct apic apic_flat; -struct apic __read_mostly *apic = &apic_flat; +struct apic *apic __ro_after_init = &apic_flat; EXPORT_SYMBOL_GPL(apic); static int flat_acpi_madt_oem_check(char *oem_id, char *oem_table_id) @@ -154,7 +154,7 @@ static int flat_probe(void) return 1; } -static struct apic apic_flat = { +static struct apic apic_flat __ro_after_init = { .name = "flat", .probe = flat_probe, .acpi_madt_oem_check = flat_acpi_madt_oem_check, @@ -248,7 +248,7 @@ static int physflat_probe(void) return 0; } -static struct apic apic_physflat = { +static struct apic apic_physflat __ro_after_init = { .name = "physical flat", .probe = physflat_probe, diff --git a/arch/x86/kernel/apic/apic_noop.c b/arch/x86/kernel/apic/apic_noop.c index c05688b2deff..b109e4389c92 100644 --- a/arch/x86/kernel/apic/apic_noop.c +++ b/arch/x86/kernel/apic/apic_noop.c @@ -108,7 +108,7 @@ static void noop_apic_write(u32 reg, u32 v) WARN_ON_ONCE(boot_cpu_has(X86_FEATURE_APIC) && !disable_apic); } -struct apic apic_noop = { +struct apic apic_noop __ro_after_init = { .name = "noop", .probe = noop_probe, .acpi_madt_oem_check = NULL, diff --git a/arch/x86/kernel/apic/bigsmp_32.c b/arch/x86/kernel/apic/bigsmp_32.c index 06dbaa458bfe..56012010332c 100644 --- a/arch/x86/kernel/apic/bigsmp_32.c +++ b/arch/x86/kernel/apic/bigsmp_32.c @@ -142,7 +142,7 @@ static int probe_bigsmp(void) return dmi_bigsmp; } -static struct apic apic_bigsmp = { +static struct apic apic_bigsmp __ro_after_init = { .name = "bigsmp", .probe = probe_bigsmp, diff --git a/arch/x86/kernel/apic/msi.c b/arch/x86/kernel/apic/msi.c index ade25320df96..015bbf30e3e3 100644 --- a/arch/x86/kernel/apic/msi.c +++ b/arch/x86/kernel/apic/msi.c @@ -269,7 +269,7 @@ static void hpet_msi_write_msg(struct irq_data *data, struct msi_msg *msg) hpet_msi_write(irq_data_get_irq_handler_data(data), msg); } -static struct irq_chip hpet_msi_controller = { +static struct irq_chip hpet_msi_controller __ro_after_init = { .name = "HPET-MSI", .irq_unmask = hpet_msi_unmask, .irq_mask = hpet_msi_mask, diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c index 563096267ca2..c48264e202fd 100644 --- a/arch/x86/kernel/apic/probe_32.c +++ b/arch/x86/kernel/apic/probe_32.c @@ -72,7 +72,7 @@ static int probe_default(void) return 1; } -static struct apic apic_default = { +static struct apic apic_default __ro_after_init = { .name = "default", .probe = probe_default, @@ -126,7 +126,7 @@ static struct apic apic_default = { apic_driver(apic_default); -struct apic *apic = &apic_default; +struct apic *apic __ro_after_init = &apic_default; EXPORT_SYMBOL_GPL(apic); static int cmdline_apic __initdata; diff --git a/arch/x86/kernel/apic/x2apic_cluster.c b/arch/x86/kernel/apic/x2apic_cluster.c index 54f35d988025..200af5ae9662 100644 --- a/arch/x86/kernel/apic/x2apic_cluster.c +++ b/arch/x86/kernel/apic/x2apic_cluster.c @@ -227,7 +227,7 @@ static void cluster_vector_allocation_domain(int cpu, struct cpumask *retmask, cpumask_and(retmask, mask, per_cpu(cpus_in_cluster, cpu)); } -static struct apic apic_x2apic_cluster = { +static struct apic apic_x2apic_cluster __ro_after_init = { .name = "cluster x2apic", .probe = x2apic_cluster_probe, diff --git a/arch/x86/kernel/apic/x2apic_phys.c b/arch/x86/kernel/apic/x2apic_phys.c index 4f13f54f1b1f..ff111f05a314 100644 --- a/arch/x86/kernel/apic/x2apic_phys.c +++ b/arch/x86/kernel/apic/x2apic_phys.c @@ -98,7 +98,7 @@ static int x2apic_phys_probe(void) return apic == &apic_x2apic_phys; } -static struct apic apic_x2apic_phys = { +static struct apic apic_x2apic_phys __ro_after_init = { .name = "physical x2apic", .probe = x2apic_phys_probe, diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c index cb0673c1e940..b9f6157d4271 100644 --- a/arch/x86/kernel/apic/x2apic_uv_x.c +++ b/arch/x86/kernel/apic/x2apic_uv_x.c @@ -560,7 +560,7 @@ static int uv_probe(void) return apic == &apic_x2apic_uv_x; } -static struct apic __refdata apic_x2apic_uv_x = { +static struct apic apic_x2apic_uv_x __ro_after_init = { .name = "UV large system", .probe = uv_probe, diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c index 2bd5c6ff7ee7..c62e015b126c 100644 --- a/arch/x86/kernel/asm-offsets.c +++ b/arch/x86/kernel/asm-offsets.c @@ -29,10 +29,13 @@ void common(void) { BLANK(); - OFFSET(TI_flags, thread_info, flags); - OFFSET(TI_status, thread_info, status); + OFFSET(TASK_threadsp, task_struct, thread.sp); +#ifdef CONFIG_CC_STACKPROTECTOR + OFFSET(TASK_stack_canary, task_struct, stack_canary); +#endif BLANK(); + OFFSET(TASK_TI_flags, task_struct, thread_info.flags); OFFSET(TASK_addr_limit, task_struct, thread.addr_limit); BLANK(); diff --git a/arch/x86/kernel/asm-offsets_32.c b/arch/x86/kernel/asm-offsets_32.c index ecdc1d217dc0..880aa093268d 100644 --- a/arch/x86/kernel/asm-offsets_32.c +++ b/arch/x86/kernel/asm-offsets_32.c @@ -57,6 +57,11 @@ void foo(void) /* Size of SYSENTER_stack */ DEFINE(SIZEOF_SYSENTER_stack, sizeof(((struct tss_struct *)0)->SYSENTER_stack)); +#ifdef CONFIG_CC_STACKPROTECTOR + BLANK(); + OFFSET(stack_canary_offset, stack_canary, canary); +#endif + #if defined(CONFIG_LGUEST) || defined(CONFIG_LGUEST_GUEST) || defined(CONFIG_LGUEST_MODULE) BLANK(); OFFSET(LGUEST_DATA_irq_enabled, lguest_data, irq_enabled); diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c index d875f97d4e0b..210927ee2e74 100644 --- a/arch/x86/kernel/asm-offsets_64.c +++ b/arch/x86/kernel/asm-offsets_64.c @@ -56,6 +56,11 @@ int main(void) OFFSET(TSS_sp0, tss_struct, x86_tss.sp0); BLANK(); +#ifdef CONFIG_CC_STACKPROTECTOR + DEFINE(stack_canary_offset, offsetof(union irq_stack_union, stack_canary)); + BLANK(); +#endif + DEFINE(__NR_syscall_max, sizeof(syscalls_64) - 1); DEFINE(NR_syscalls, sizeof(syscalls_64)); diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index bcc9ccc220c9..9bd910a7dd0a 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1264,9 +1264,14 @@ static __init int setup_disablecpuid(char *arg) __setup("clearcpuid=", setup_disablecpuid); #ifdef CONFIG_X86_64 -struct desc_ptr idt_descr = { NR_VECTORS * 16 - 1, (unsigned long) idt_table }; -struct desc_ptr debug_idt_descr = { NR_VECTORS * 16 - 1, - (unsigned long) debug_idt_table }; +struct desc_ptr idt_descr __ro_after_init = { + .size = NR_VECTORS * 16 - 1, + .address = (unsigned long) idt_table, +}; +const struct desc_ptr debug_idt_descr = { + .size = NR_VECTORS * 16 - 1, + .address = (unsigned long) debug_idt_table, +}; DEFINE_PER_CPU_FIRST(union irq_stack_union, irq_stack_union) __aligned(PAGE_SIZE) __visible; @@ -1280,7 +1285,7 @@ DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned = EXPORT_PER_CPU_SYMBOL(current_task); DEFINE_PER_CPU(char *, irq_stack_ptr) = - init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64; + init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE; DEFINE_PER_CPU(unsigned int, irq_count) __visible = -1; @@ -1304,11 +1309,6 @@ static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks /* May not be marked __init: used by software suspend */ void syscall_init(void) { - /* - * LSTAR and STAR live in a bit strange symbiosis. - * They both write to the same internal register. STAR allows to - * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip. - */ wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS); wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64); diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c index 28f1b54b7fad..24e87e74990d 100644 --- a/arch/x86/kernel/cpu/mtrr/main.c +++ b/arch/x86/kernel/cpu/mtrr/main.c @@ -72,14 +72,14 @@ static DEFINE_MUTEX(mtrr_mutex); u64 size_or_mask, size_and_mask; static bool mtrr_aps_delayed_init; -static const struct mtrr_ops *mtrr_ops[X86_VENDOR_NUM]; +static const struct mtrr_ops *mtrr_ops[X86_VENDOR_NUM] __ro_after_init; const struct mtrr_ops *mtrr_if; static void set_mtrr(unsigned int reg, unsigned long base, unsigned long size, mtrr_type type); -void set_mtrr_ops(const struct mtrr_ops *ops) +void __init set_mtrr_ops(const struct mtrr_ops *ops) { if (ops->vendor && ops->vendor < X86_VENDOR_NUM) mtrr_ops[ops->vendor] = ops; diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.h b/arch/x86/kernel/cpu/mtrr/mtrr.h index 6c7ced07d16d..ad8bd763efa5 100644 --- a/arch/x86/kernel/cpu/mtrr/mtrr.h +++ b/arch/x86/kernel/cpu/mtrr/mtrr.h @@ -54,7 +54,7 @@ void fill_mtrr_var_range(unsigned int index, bool get_mtrr_state(void); void mtrr_bp_pat_init(void); -extern void set_mtrr_ops(const struct mtrr_ops *ops); +extern void __init set_mtrr_ops(const struct mtrr_ops *ops); extern u64 size_or_mask, size_and_mask; extern const struct mtrr_ops *mtrr_if; diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c index 92e8f0a7159c..9b7cf5c28f5f 100644 --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -17,7 +17,7 @@ #include <linux/sysfs.h> #include <asm/stacktrace.h> - +#include <asm/unwind.h> int panic_on_unrecovered_nmi; int panic_on_io_nmi; @@ -25,11 +25,29 @@ unsigned int code_bytes = 64; int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE; static int die_counter; +bool in_task_stack(unsigned long *stack, struct task_struct *task, + struct stack_info *info) +{ + unsigned long *begin = task_stack_page(task); + unsigned long *end = task_stack_page(task) + THREAD_SIZE; + + if (stack < begin || stack >= end) + return false; + + info->type = STACK_TYPE_TASK; + info->begin = begin; + info->end = end; + info->next_sp = NULL; + + return true; +} + static void printk_stack_address(unsigned long address, int reliable, - void *data) + char *log_lvl) { + touch_nmi_watchdog(); printk("%s [<%p>] %s%pB\n", - (char *)data, (void *)address, reliable ? "" : "? ", + log_lvl, (void *)address, reliable ? "" : "? ", (void *)address); } @@ -38,176 +56,120 @@ void printk_address(unsigned long address) pr_cont(" [<%p>] %pS\n", (void *)address, (void *)address); } -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -static void -print_ftrace_graph_addr(unsigned long addr, void *data, - const struct stacktrace_ops *ops, - struct task_struct *task, int *graph) +void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs, + unsigned long *stack, char *log_lvl) { - unsigned long ret_addr; - int index; - - if (addr != (unsigned long)return_to_handler) - return; - - index = task->curr_ret_stack; - - if (!task->ret_stack || index < *graph) - return; - - index -= *graph; - ret_addr = task->ret_stack[index].ret; - - ops->address(data, ret_addr, 1); + struct unwind_state state; + struct stack_info stack_info = {0}; + unsigned long visit_mask = 0; + int graph_idx = 0; - (*graph)++; -} -#else -static inline void -print_ftrace_graph_addr(unsigned long addr, void *data, - const struct stacktrace_ops *ops, - struct task_struct *task, int *graph) -{ } -#endif - -/* - * x86-64 can have up to three kernel stacks: - * process stack - * interrupt stack - * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack - */ - -static inline int valid_stack_ptr(struct task_struct *task, - void *p, unsigned int size, void *end) -{ - void *t = task_stack_page(task); - if (end) { - if (p < end && p >= (end-THREAD_SIZE)) - return 1; - else - return 0; - } - return p >= t && p < t + THREAD_SIZE - size; -} + printk("%sCall Trace:\n", log_lvl); -unsigned long -print_context_stack(struct task_struct *task, - unsigned long *stack, unsigned long bp, - const struct stacktrace_ops *ops, void *data, - unsigned long *end, int *graph) -{ - struct stack_frame *frame = (struct stack_frame *)bp; + unwind_start(&state, task, regs, stack); /* - * If we overflowed the stack into a guard page, jump back to the - * bottom of the usable stack. + * Iterate through the stacks, starting with the current stack pointer. + * Each stack has a pointer to the next one. + * + * x86-64 can have several stacks: + * - task stack + * - interrupt stack + * - HW exception stacks (double fault, nmi, debug, mce) + * + * x86-32 can have up to three stacks: + * - task stack + * - softirq stack + * - hardirq stack */ - if ((unsigned long)task_stack_page(task) - (unsigned long)stack < - PAGE_SIZE) - stack = (unsigned long *)task_stack_page(task); - - while (valid_stack_ptr(task, stack, sizeof(*stack), end)) { - unsigned long addr; - - addr = *stack; - if (__kernel_text_address(addr)) { - if ((unsigned long) stack == bp + sizeof(long)) { - ops->address(data, addr, 1); - frame = frame->next_frame; - bp = (unsigned long) frame; - } else { - ops->address(data, addr, 0); - } - print_ftrace_graph_addr(addr, data, ops, task, graph); - } - stack++; - } - return bp; -} -EXPORT_SYMBOL_GPL(print_context_stack); - -unsigned long -print_context_stack_bp(struct task_struct *task, - unsigned long *stack, unsigned long bp, - const struct stacktrace_ops *ops, void *data, - unsigned long *end, int *graph) -{ - struct stack_frame *frame = (struct stack_frame *)bp; - unsigned long *ret_addr = &frame->return_address; + for (; stack; stack = stack_info.next_sp) { + const char *str_begin, *str_end; - while (valid_stack_ptr(task, ret_addr, sizeof(*ret_addr), end)) { - unsigned long addr = *ret_addr; + /* + * If we overflowed the task stack into a guard page, jump back + * to the bottom of the usable stack. + */ + if (task_stack_page(task) - (void *)stack < PAGE_SIZE) + stack = task_stack_page(task); - if (!__kernel_text_address(addr)) + if (get_stack_info(stack, task, &stack_info, &visit_mask)) break; - if (ops->address(data, addr, 1)) - break; - frame = frame->next_frame; - ret_addr = &frame->return_address; - print_ftrace_graph_addr(addr, data, ops, task, graph); - } - - return (unsigned long)frame; -} -EXPORT_SYMBOL_GPL(print_context_stack_bp); - -static int print_trace_stack(void *data, char *name) -{ - printk("%s <%s> ", (char *)data, name); - return 0; -} - -/* - * Print one address/symbol entries per line. - */ -static int print_trace_address(void *data, unsigned long addr, int reliable) -{ - touch_nmi_watchdog(); - printk_stack_address(addr, reliable, data); - return 0; -} - -static const struct stacktrace_ops print_trace_ops = { - .stack = print_trace_stack, - .address = print_trace_address, - .walk_stack = print_context_stack, -}; - -void -show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs, - unsigned long *stack, unsigned long bp, char *log_lvl) -{ - printk("%sCall Trace:\n", log_lvl); - dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl); -} + stack_type_str(stack_info.type, &str_begin, &str_end); + if (str_begin) + printk("%s <%s> ", log_lvl, str_begin); + + /* + * Scan the stack, printing any text addresses we find. At the + * same time, follow proper stack frames with the unwinder. + * + * Addresses found during the scan which are not reported by + * the unwinder are considered to be additional clues which are + * sometimes useful for debugging and are prefixed with '?'. + * This also serves as a failsafe option in case the unwinder + * goes off in the weeds. + */ + for (; stack < stack_info.end; stack++) { + unsigned long real_addr; + int reliable = 0; + unsigned long addr = *stack; + unsigned long *ret_addr_p = + unwind_get_return_address_ptr(&state); + + if (!__kernel_text_address(addr)) + continue; + + if (stack == ret_addr_p) + reliable = 1; + + /* + * When function graph tracing is enabled for a + * function, its return address on the stack is + * replaced with the address of an ftrace handler + * (return_to_handler). In that case, before printing + * the "real" address, we want to print the handler + * address as an "unreliable" hint that function graph + * tracing was involved. + */ + real_addr = ftrace_graph_ret_addr(task, &graph_idx, + addr, stack); + if (real_addr != addr) + printk_stack_address(addr, 0, log_lvl); + printk_stack_address(real_addr, reliable, log_lvl); + + if (!reliable) + continue; + + /* + * Get the next frame from the unwinder. No need to + * check for an error: if anything goes wrong, the rest + * of the addresses will just be printed as unreliable. + */ + unwind_next_frame(&state); + } -void show_trace(struct task_struct *task, struct pt_regs *regs, - unsigned long *stack, unsigned long bp) -{ - show_trace_log_lvl(task, regs, stack, bp, ""); + if (str_end) + printk("%s <%s> ", log_lvl, str_end); + } } void show_stack(struct task_struct *task, unsigned long *sp) { - unsigned long bp = 0; - unsigned long stack; + task = task ? : current; /* * Stack frames below this one aren't interesting. Don't show them * if we're printing for %current. */ - if (!sp && (!task || task == current)) { - sp = &stack; - bp = stack_frame(current, NULL); - } + if (!sp && task == current) + sp = get_stack_pointer(current, NULL); - show_stack_log_lvl(task, NULL, sp, bp, ""); + show_stack_log_lvl(task, NULL, sp, ""); } void show_stack_regs(struct pt_regs *regs) { - show_stack_log_lvl(current, regs, (unsigned long *)regs->sp, regs->bp, ""); + show_stack_log_lvl(current, regs, NULL, ""); } static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED; diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index 09675712eba8..06eb322b5f9f 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -16,93 +16,121 @@ #include <asm/stacktrace.h> -static void *is_irq_stack(void *p, void *irq) +void stack_type_str(enum stack_type type, const char **begin, const char **end) { - if (p < irq || p >= (irq + THREAD_SIZE)) - return NULL; - return irq + THREAD_SIZE; + switch (type) { + case STACK_TYPE_IRQ: + case STACK_TYPE_SOFTIRQ: + *begin = "IRQ"; + *end = "EOI"; + break; + default: + *begin = NULL; + *end = NULL; + } } - -static void *is_hardirq_stack(unsigned long *stack, int cpu) +static bool in_hardirq_stack(unsigned long *stack, struct stack_info *info) { - void *irq = per_cpu(hardirq_stack, cpu); + unsigned long *begin = (unsigned long *)this_cpu_read(hardirq_stack); + unsigned long *end = begin + (THREAD_SIZE / sizeof(long)); - return is_irq_stack(stack, irq); -} + /* + * This is a software stack, so 'end' can be a valid stack pointer. + * It just means the stack is empty. + */ + if (stack < begin || stack > end) + return false; -static void *is_softirq_stack(unsigned long *stack, int cpu) -{ - void *irq = per_cpu(softirq_stack, cpu); + info->type = STACK_TYPE_IRQ; + info->begin = begin; + info->end = end; - return is_irq_stack(stack, irq); + /* + * See irq_32.c -- the next stack pointer is stored at the beginning of + * the stack. + */ + info->next_sp = (unsigned long *)*begin; + + return true; } -void dump_trace(struct task_struct *task, struct pt_regs *regs, - unsigned long *stack, unsigned long bp, - const struct stacktrace_ops *ops, void *data) +static bool in_softirq_stack(unsigned long *stack, struct stack_info *info) { - const unsigned cpu = get_cpu(); - int graph = 0; - u32 *prev_esp; + unsigned long *begin = (unsigned long *)this_cpu_read(softirq_stack); + unsigned long *end = begin + (THREAD_SIZE / sizeof(long)); - if (!task) - task = current; + /* + * This is a software stack, so 'end' can be a valid stack pointer. + * It just means the stack is empty. + */ + if (stack < begin || stack > end) + return false; - if (!stack) { - unsigned long dummy; + info->type = STACK_TYPE_SOFTIRQ; + info->begin = begin; + info->end = end; - stack = &dummy; - if (task != current) - stack = (unsigned long *)task->thread.sp; - } + /* + * The next stack pointer is stored at the beginning of the stack. + * See irq_32.c. + */ + info->next_sp = (unsigned long *)*begin; - if (!bp) - bp = stack_frame(task, regs); + return true; +} - for (;;) { - void *end_stack; +int get_stack_info(unsigned long *stack, struct task_struct *task, + struct stack_info *info, unsigned long *visit_mask) +{ + if (!stack) + goto unknown; - end_stack = is_hardirq_stack(stack, cpu); - if (!end_stack) - end_stack = is_softirq_stack(stack, cpu); + task = task ? : current; - bp = ops->walk_stack(task, stack, bp, ops, data, - end_stack, &graph); + if (in_task_stack(stack, task, info)) + goto recursion_check; - /* Stop if not on irq stack */ - if (!end_stack) - break; + if (task != current) + goto unknown; - /* The previous esp is saved on the bottom of the stack */ - prev_esp = (u32 *)(end_stack - THREAD_SIZE); - stack = (unsigned long *)*prev_esp; - if (!stack) - break; + if (in_hardirq_stack(stack, info)) + goto recursion_check; - if (ops->stack(data, "IRQ") < 0) - break; - touch_nmi_watchdog(); + if (in_softirq_stack(stack, info)) + goto recursion_check; + + goto unknown; + +recursion_check: + /* + * Make sure we don't iterate through any given stack more than once. + * If it comes up a second time then there's something wrong going on: + * just break out and report an unknown stack type. + */ + if (visit_mask) { + if (*visit_mask & (1UL << info->type)) + goto unknown; + *visit_mask |= 1UL << info->type; } - put_cpu(); + + return 0; + +unknown: + info->type = STACK_TYPE_UNKNOWN; + return -EINVAL; } -EXPORT_SYMBOL(dump_trace); -void -show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, - unsigned long *sp, unsigned long bp, char *log_lvl) +void show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, + unsigned long *sp, char *log_lvl) { unsigned long *stack; int i; - if (sp == NULL) { - if (regs) - sp = (unsigned long *)regs->sp; - else if (task) - sp = (unsigned long *)task->thread.sp; - else - sp = (unsigned long *)&sp; - } + if (!try_get_task_stack(task)) + return; + + sp = sp ? : get_stack_pointer(task, regs); stack = sp; for (i = 0; i < kstack_depth_to_print; i++) { @@ -117,7 +145,9 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, touch_nmi_watchdog(); } pr_cont("\n"); - show_trace_log_lvl(task, regs, sp, bp, log_lvl); + show_trace_log_lvl(task, regs, sp, log_lvl); + + put_task_stack(task); } @@ -139,7 +169,7 @@ void show_regs(struct pt_regs *regs) u8 *ip; pr_emerg("Stack:\n"); - show_stack_log_lvl(NULL, regs, ®s->sp, 0, KERN_EMERG); + show_stack_log_lvl(current, regs, NULL, KERN_EMERG); pr_emerg("Code:"); diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c index 9ee4520ce83c..36cf1a498227 100644 --- a/arch/x86/kernel/dumpstack_64.c +++ b/arch/x86/kernel/dumpstack_64.c @@ -16,261 +16,145 @@ #include <asm/stacktrace.h> +static char *exception_stack_names[N_EXCEPTION_STACKS] = { + [ DOUBLEFAULT_STACK-1 ] = "#DF", + [ NMI_STACK-1 ] = "NMI", + [ DEBUG_STACK-1 ] = "#DB", + [ MCE_STACK-1 ] = "#MC", +}; -#define N_EXCEPTION_STACKS_END \ - (N_EXCEPTION_STACKS + DEBUG_STKSZ/EXCEPTION_STKSZ - 2) - -static char x86_stack_ids[][8] = { - [ DEBUG_STACK-1 ] = "#DB", - [ NMI_STACK-1 ] = "NMI", - [ DOUBLEFAULT_STACK-1 ] = "#DF", - [ MCE_STACK-1 ] = "#MC", -#if DEBUG_STKSZ > EXCEPTION_STKSZ - [ N_EXCEPTION_STACKS ... - N_EXCEPTION_STACKS_END ] = "#DB[?]" -#endif +static unsigned long exception_stack_sizes[N_EXCEPTION_STACKS] = { + [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ, + [DEBUG_STACK - 1] = DEBUG_STKSZ }; -static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack, - unsigned *usedp, char **idp) +void stack_type_str(enum stack_type type, const char **begin, const char **end) { - unsigned k; - - /* - * Iterate over all exception stacks, and figure out whether - * 'stack' is in one of them: - */ - for (k = 0; k < N_EXCEPTION_STACKS; k++) { - unsigned long end = per_cpu(orig_ist, cpu).ist[k]; - /* - * Is 'stack' above this exception frame's end? - * If yes then skip to the next frame. - */ - if (stack >= end) - continue; - /* - * Is 'stack' above this exception frame's start address? - * If yes then we found the right frame. - */ - if (stack >= end - EXCEPTION_STKSZ) { - /* - * Make sure we only iterate through an exception - * stack once. If it comes up for the second time - * then there's something wrong going on - just - * break out and return NULL: - */ - if (*usedp & (1U << k)) - break; - *usedp |= 1U << k; - *idp = x86_stack_ids[k]; - return (unsigned long *)end; - } - /* - * If this is a debug stack, and if it has a larger size than - * the usual exception stacks, then 'stack' might still - * be within the lower portion of the debug stack: - */ -#if DEBUG_STKSZ > EXCEPTION_STKSZ - if (k == DEBUG_STACK - 1 && stack >= end - DEBUG_STKSZ) { - unsigned j = N_EXCEPTION_STACKS - 1; - - /* - * Black magic. A large debug stack is composed of - * multiple exception stack entries, which we - * iterate through now. Dont look: - */ - do { - ++j; - end -= EXCEPTION_STKSZ; - x86_stack_ids[j][4] = '1' + - (j - N_EXCEPTION_STACKS); - } while (stack < end - EXCEPTION_STKSZ); - if (*usedp & (1U << j)) - break; - *usedp |= 1U << j; - *idp = x86_stack_ids[j]; - return (unsigned long *)end; - } -#endif + BUILD_BUG_ON(N_EXCEPTION_STACKS != 4); + + switch (type) { + case STACK_TYPE_IRQ: + *begin = "IRQ"; + *end = "EOI"; + break; + case STACK_TYPE_EXCEPTION ... STACK_TYPE_EXCEPTION_LAST: + *begin = exception_stack_names[type - STACK_TYPE_EXCEPTION]; + *end = "EOE"; + break; + default: + *begin = NULL; + *end = NULL; } - return NULL; } -static inline int -in_irq_stack(unsigned long *stack, unsigned long *irq_stack, - unsigned long *irq_stack_end) +static bool in_exception_stack(unsigned long *stack, struct stack_info *info) { - return (stack >= irq_stack && stack < irq_stack_end); -} - -static const unsigned long irq_stack_size = - (IRQ_STACK_SIZE - 64) / sizeof(unsigned long); - -enum stack_type { - STACK_IS_UNKNOWN, - STACK_IS_NORMAL, - STACK_IS_EXCEPTION, - STACK_IS_IRQ, -}; - -static enum stack_type -analyze_stack(int cpu, struct task_struct *task, unsigned long *stack, - unsigned long **stack_end, unsigned long *irq_stack, - unsigned *used, char **id) -{ - unsigned long addr; + unsigned long *begin, *end; + struct pt_regs *regs; + unsigned k; - addr = ((unsigned long)stack & (~(THREAD_SIZE - 1))); - if ((unsigned long)task_stack_page(task) == addr) - return STACK_IS_NORMAL; + BUILD_BUG_ON(N_EXCEPTION_STACKS != 4); - *stack_end = in_exception_stack(cpu, (unsigned long)stack, - used, id); - if (*stack_end) - return STACK_IS_EXCEPTION; + for (k = 0; k < N_EXCEPTION_STACKS; k++) { + end = (unsigned long *)raw_cpu_ptr(&orig_ist)->ist[k]; + begin = end - (exception_stack_sizes[k] / sizeof(long)); + regs = (struct pt_regs *)end - 1; - if (!irq_stack) - return STACK_IS_NORMAL; + if (stack < begin || stack >= end) + continue; - *stack_end = irq_stack; - irq_stack = irq_stack - irq_stack_size; + info->type = STACK_TYPE_EXCEPTION + k; + info->begin = begin; + info->end = end; + info->next_sp = (unsigned long *)regs->sp; - if (in_irq_stack(stack, irq_stack, *stack_end)) - return STACK_IS_IRQ; + return true; + } - return STACK_IS_UNKNOWN; + return false; } -/* - * x86-64 can have up to three kernel stacks: - * process stack - * interrupt stack - * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack - */ - -void dump_trace(struct task_struct *task, struct pt_regs *regs, - unsigned long *stack, unsigned long bp, - const struct stacktrace_ops *ops, void *data) +static bool in_irq_stack(unsigned long *stack, struct stack_info *info) { - const unsigned cpu = get_cpu(); - unsigned long *irq_stack = (unsigned long *)per_cpu(irq_stack_ptr, cpu); - unsigned long dummy; - unsigned used = 0; - int graph = 0; - int done = 0; - - if (!task) - task = current; - - if (!stack) { - if (regs) - stack = (unsigned long *)regs->sp; - else if (task != current) - stack = (unsigned long *)task->thread.sp; - else - stack = &dummy; - } + unsigned long *end = (unsigned long *)this_cpu_read(irq_stack_ptr); + unsigned long *begin = end - (IRQ_STACK_SIZE / sizeof(long)); - if (!bp) - bp = stack_frame(task, regs); /* - * Print function call entries in all stacks, starting at the - * current stack address. If the stacks consist of nested - * exceptions + * This is a software stack, so 'end' can be a valid stack pointer. + * It just means the stack is empty. */ - while (!done) { - unsigned long *stack_end; - enum stack_type stype; - char *id; + if (stack < begin || stack > end) + return false; - stype = analyze_stack(cpu, task, stack, &stack_end, - irq_stack, &used, &id); + info->type = STACK_TYPE_IRQ; + info->begin = begin; + info->end = end; - /* Default finish unless specified to continue */ - done = 1; + /* + * The next stack pointer is the first thing pushed by the entry code + * after switching to the irq stack. + */ + info->next_sp = (unsigned long *)*(end - 1); - switch (stype) { + return true; +} - /* Break out early if we are on the thread stack */ - case STACK_IS_NORMAL: - break; +int get_stack_info(unsigned long *stack, struct task_struct *task, + struct stack_info *info, unsigned long *visit_mask) +{ + if (!stack) + goto unknown; - case STACK_IS_EXCEPTION: + task = task ? : current; - if (ops->stack(data, id) < 0) - break; + if (in_task_stack(stack, task, info)) + goto recursion_check; - bp = ops->walk_stack(task, stack, bp, ops, - data, stack_end, &graph); - ops->stack(data, "<EOE>"); - /* - * We link to the next stack via the - * second-to-last pointer (index -2 to end) in the - * exception stack: - */ - stack = (unsigned long *) stack_end[-2]; - done = 0; - break; + if (task != current) + goto unknown; - case STACK_IS_IRQ: + if (in_exception_stack(stack, info)) + goto recursion_check; - if (ops->stack(data, "IRQ") < 0) - break; - bp = ops->walk_stack(task, stack, bp, - ops, data, stack_end, &graph); - /* - * We link to the next stack (which would be - * the process stack normally) the last - * pointer (index -1 to end) in the IRQ stack: - */ - stack = (unsigned long *) (stack_end[-1]); - irq_stack = NULL; - ops->stack(data, "EOI"); - done = 0; - break; + if (in_irq_stack(stack, info)) + goto recursion_check; - case STACK_IS_UNKNOWN: - ops->stack(data, "UNK"); - break; - } - } + goto unknown; +recursion_check: /* - * This handles the process stack: + * Make sure we don't iterate through any given stack more than once. + * If it comes up a second time then there's something wrong going on: + * just break out and report an unknown stack type. */ - bp = ops->walk_stack(task, stack, bp, ops, data, NULL, &graph); - put_cpu(); + if (visit_mask) { + if (*visit_mask & (1UL << info->type)) + goto unknown; + *visit_mask |= 1UL << info->type; + } + + return 0; + +unknown: + info->type = STACK_TYPE_UNKNOWN; + return -EINVAL; } -EXPORT_SYMBOL(dump_trace); -void -show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, - unsigned long *sp, unsigned long bp, char *log_lvl) +void show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, + unsigned long *sp, char *log_lvl) { unsigned long *irq_stack_end; unsigned long *irq_stack; unsigned long *stack; - int cpu; int i; - preempt_disable(); - cpu = smp_processor_id(); + if (!try_get_task_stack(task)) + return; - irq_stack_end = (unsigned long *)(per_cpu(irq_stack_ptr, cpu)); - irq_stack = (unsigned long *)(per_cpu(irq_stack_ptr, cpu) - IRQ_STACK_SIZE); + irq_stack_end = (unsigned long *)this_cpu_read(irq_stack_ptr); + irq_stack = irq_stack_end - (IRQ_STACK_SIZE / sizeof(long)); - /* - * Debugging aid: "show_stack(NULL, NULL);" prints the - * back trace for this cpu: - */ - if (sp == NULL) { - if (regs) - sp = (unsigned long *)regs->sp; - else if (task) - sp = (unsigned long *)task->thread.sp; - else - sp = (unsigned long *)&sp; - } + sp = sp ? : get_stack_pointer(task, regs); stack = sp; for (i = 0; i < kstack_depth_to_print; i++) { @@ -299,18 +183,17 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, stack++; touch_nmi_watchdog(); } - preempt_enable(); pr_cont("\n"); - show_trace_log_lvl(task, regs, sp, bp, log_lvl); + show_trace_log_lvl(task, regs, sp, log_lvl); + + put_task_stack(task); } void show_regs(struct pt_regs *regs) { int i; - unsigned long sp; - sp = regs->sp; show_regs_print_info(KERN_DEFAULT); __show_regs(regs, 1); @@ -325,8 +208,7 @@ void show_regs(struct pt_regs *regs) u8 *ip; printk(KERN_DEFAULT "Stack:\n"); - show_stack_log_lvl(NULL, regs, (unsigned long *)sp, - 0, KERN_DEFAULT); + show_stack_log_lvl(current, regs, NULL, KERN_DEFAULT); printk(KERN_DEFAULT "Code: "); diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c index 93982aebb398..2f2b8c7ccb85 100644 --- a/arch/x86/kernel/fpu/init.c +++ b/arch/x86/kernel/fpu/init.c @@ -317,7 +317,6 @@ static void __init fpu__init_system_ctx_switch(void) on_boot_cpu = 0; WARN_ON_FPU(current->thread.fpu.fpstate_active); - current_thread_info()->status = 0; if (boot_cpu_has(X86_FEATURE_XSAVEOPT) && eagerfpu != DISABLE) eagerfpu = ENABLE; diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index d036cfb4495d..8639bb2ae058 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -1029,7 +1029,7 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, } if (ftrace_push_return_trace(old, self_addr, &trace.depth, - frame_pointer) == -EBUSY) { + frame_pointer, parent) == -EBUSY) { *parent = old; return; } diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index 6f8902b0d151..5f401262f12d 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -94,7 +94,7 @@ RESERVE_BRK(pagetables, INIT_MAP_SIZE) */ __HEAD ENTRY(startup_32) - movl pa(stack_start),%ecx + movl pa(initial_stack),%ecx /* test KEEP_SEGMENTS flag to see if the bootloader is asking us to not reload segments */ @@ -286,7 +286,7 @@ num_subarch_entries = (. - subarch_entries) / 4 * start_secondary(). */ ENTRY(start_cpu0) - movl stack_start, %ecx + movl initial_stack, %ecx movl %ecx, %esp jmp *(initial_code) ENDPROC(start_cpu0) @@ -307,7 +307,7 @@ ENTRY(startup_32_smp) movl %eax,%es movl %eax,%fs movl %eax,%gs - movl pa(stack_start),%ecx + movl pa(initial_stack),%ecx movl %eax,%ss leal -__PAGE_OFFSET(%ecx),%esp @@ -703,7 +703,7 @@ ENTRY(initial_page_table) .data .balign 4 -ENTRY(stack_start) +ENTRY(initial_stack) .long init_thread_union+THREAD_SIZE __INITRODATA diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 9f8efc9f0075..c98a559c346e 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -66,7 +66,7 @@ startup_64: */ /* - * Setup stack for verify_cpu(). "-8" because stack_start is defined + * Setup stack for verify_cpu(). "-8" because initial_stack is defined * this way, see below. Our best guess is a NULL ptr for stack * termination heuristics and we don't want to break anything which * might depend on it (kgdb, ...). @@ -226,7 +226,7 @@ ENTRY(secondary_startup_64) movq %rax, %cr0 /* Setup a boot time stack */ - movq stack_start(%rip), %rsp + movq initial_stack(%rip), %rsp /* zero EFLAGS after setting rsp */ pushq $0 @@ -310,7 +310,7 @@ ENDPROC(secondary_startup_64) * start_secondary(). */ ENTRY(start_cpu0) - movq stack_start(%rip),%rsp + movq initial_stack(%rip),%rsp movq initial_code(%rip),%rax pushq $0 # fake return address to stop unwinder pushq $__KERNEL_CS # set correct cs @@ -319,17 +319,15 @@ ENTRY(start_cpu0) ENDPROC(start_cpu0) #endif - /* SMP bootup changes these two */ + /* Both SMP bootup and ACPI suspend change these variables */ __REFDATA .balign 8 GLOBAL(initial_code) .quad x86_64_start_kernel GLOBAL(initial_gs) .quad INIT_PER_CPU_VAR(irq_stack_union) - - GLOBAL(stack_start) + GLOBAL(initial_stack) .quad init_thread_union+THREAD_SIZE-8 - .word 0 __FINITDATA bad_address: diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c index 4a7903714065..9ebd0b0e73d9 100644 --- a/arch/x86/kernel/irq_64.c +++ b/arch/x86/kernel/irq_64.c @@ -40,8 +40,7 @@ static inline void stack_overflow_check(struct pt_regs *regs) if (user_mode(regs)) return; - if (regs->sp >= curbase + sizeof(struct thread_info) + - sizeof(struct pt_regs) + STACK_TOP_MARGIN && + if (regs->sp >= curbase + sizeof(struct pt_regs) + STACK_TOP_MARGIN && regs->sp <= curbase + THREAD_SIZE) return; diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c index 04cde527d728..8e36f249646e 100644 --- a/arch/x86/kernel/kgdb.c +++ b/arch/x86/kernel/kgdb.c @@ -50,6 +50,7 @@ #include <asm/apicdef.h> #include <asm/apic.h> #include <asm/nmi.h> +#include <asm/switch_to.h> struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = { @@ -166,21 +167,19 @@ void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p) gdb_regs[GDB_DX] = 0; gdb_regs[GDB_SI] = 0; gdb_regs[GDB_DI] = 0; - gdb_regs[GDB_BP] = *(unsigned long *)p->thread.sp; + gdb_regs[GDB_BP] = ((struct inactive_task_frame *)p->thread.sp)->bp; #ifdef CONFIG_X86_32 gdb_regs[GDB_DS] = __KERNEL_DS; gdb_regs[GDB_ES] = __KERNEL_DS; gdb_regs[GDB_PS] = 0; gdb_regs[GDB_CS] = __KERNEL_CS; - gdb_regs[GDB_PC] = p->thread.ip; gdb_regs[GDB_SS] = __KERNEL_DS; gdb_regs[GDB_FS] = 0xFFFF; gdb_regs[GDB_GS] = 0xFFFF; #else - gdb_regs32[GDB_PS] = *(unsigned long *)(p->thread.sp + 8); + gdb_regs32[GDB_PS] = 0; gdb_regs32[GDB_CS] = __KERNEL_CS; gdb_regs32[GDB_SS] = __KERNEL_DS; - gdb_regs[GDB_PC] = 0; gdb_regs[GDB_R8] = 0; gdb_regs[GDB_R9] = 0; gdb_regs[GDB_R10] = 0; @@ -190,6 +189,7 @@ void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p) gdb_regs[GDB_R14] = 0; gdb_regs[GDB_R15] = 0; #endif + gdb_regs[GDB_PC] = 0; gdb_regs[GDB_SP] = p->thread.sp; } diff --git a/arch/x86/kernel/ksysfs.c b/arch/x86/kernel/ksysfs.c index c2bedaea11f7..4afc67f5facc 100644 --- a/arch/x86/kernel/ksysfs.c +++ b/arch/x86/kernel/ksysfs.c @@ -184,7 +184,7 @@ out: static struct kobj_attribute type_attr = __ATTR_RO(type); -static struct bin_attribute data_attr = { +static struct bin_attribute data_attr __ro_after_init = { .attr = { .name = "data", .mode = S_IRUGO, diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index 3692249a70f1..60b9949f1e65 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -29,7 +29,7 @@ #include <asm/x86_init.h> #include <asm/reboot.h> -static int kvmclock = 1; +static int kvmclock __ro_after_init = 1; static int msr_kvm_system_time = MSR_KVM_SYSTEM_TIME; static int msr_kvm_wall_clock = MSR_KVM_WALL_CLOCK; static cycle_t kvm_sched_clock_offset; diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 1acfd76e3e26..bbf3d5933eaa 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -332,7 +332,6 @@ __visible struct pv_cpu_ops pv_cpu_ops = { .read_cr0 = native_read_cr0, .write_cr0 = native_write_cr0, .read_cr4 = native_read_cr4, - .read_cr4_safe = native_read_cr4_safe, .write_cr4 = native_write_cr4, #ifdef CONFIG_X86_64 .read_cr8 = native_read_cr8, @@ -389,7 +388,7 @@ NOKPROBE_SYMBOL(native_load_idt); #define PTE_IDENT __PV_IS_CALLEE_SAVE(_paravirt_ident_64) #endif -struct pv_mmu_ops pv_mmu_ops = { +struct pv_mmu_ops pv_mmu_ops __ro_after_init = { .read_cr2 = native_read_cr2, .write_cr2 = native_write_cr2, diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 62c0b0ea2ce4..4002b475171c 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -32,6 +32,7 @@ #include <asm/tlbflush.h> #include <asm/mce.h> #include <asm/vm86.h> +#include <asm/switch_to.h> /* * per-CPU TSS segments. Threads are completely 'soft' on Linux, @@ -513,6 +514,17 @@ unsigned long arch_randomize_brk(struct mm_struct *mm) } /* + * Return saved PC of a blocked thread. + * What is this good for? it will be always the scheduler or ret_from_fork. + */ +unsigned long thread_saved_pc(struct task_struct *tsk) +{ + struct inactive_task_frame *frame = + (struct inactive_task_frame *) READ_ONCE(tsk->thread.sp); + return READ_ONCE_NOCHECK(frame->ret_addr); +} + +/* * Called from fs/proc with a reference on @p to find the function * which called into schedule(). This needs to be done carefully * because the task might wake up and we might look at a stack @@ -520,15 +532,18 @@ unsigned long arch_randomize_brk(struct mm_struct *mm) */ unsigned long get_wchan(struct task_struct *p) { - unsigned long start, bottom, top, sp, fp, ip; + unsigned long start, bottom, top, sp, fp, ip, ret = 0; int count = 0; if (!p || p == current || p->state == TASK_RUNNING) return 0; + if (!try_get_task_stack(p)) + return 0; + start = (unsigned long)task_stack_page(p); if (!start) - return 0; + goto out; /* * Layout of the stack page: @@ -537,9 +552,7 @@ unsigned long get_wchan(struct task_struct *p) * PADDING * ----------- top = topmax - TOP_OF_KERNEL_STACK_PADDING * stack - * ----------- bottom = start + sizeof(thread_info) - * thread_info - * ----------- start + * ----------- bottom = start * * The tasks stack pointer points at the location where the * framepointer is stored. The data on the stack is: @@ -550,20 +563,25 @@ unsigned long get_wchan(struct task_struct *p) */ top = start + THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING; top -= 2 * sizeof(unsigned long); - bottom = start + sizeof(struct thread_info); + bottom = start; sp = READ_ONCE(p->thread.sp); if (sp < bottom || sp > top) - return 0; + goto out; - fp = READ_ONCE_NOCHECK(*(unsigned long *)sp); + fp = READ_ONCE_NOCHECK(((struct inactive_task_frame *)sp)->bp); do { if (fp < bottom || fp > top) - return 0; + goto out; ip = READ_ONCE_NOCHECK(*(unsigned long *)(fp + sizeof(unsigned long))); - if (!in_sched_functions(ip)) - return ip; + if (!in_sched_functions(ip)) { + ret = ip; + goto out; + } fp = READ_ONCE_NOCHECK(*(unsigned long *)fp); } while (count++ < 16 && p->state != TASK_RUNNING); - return 0; + +out: + put_task_stack(p); + return ret; } diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index d86be29c38c7..bd7be8efdc4c 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -55,17 +55,6 @@ #include <asm/switch_to.h> #include <asm/vm86.h> -asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); -asmlinkage void ret_from_kernel_thread(void) __asm__("ret_from_kernel_thread"); - -/* - * Return saved PC of a blocked thread. - */ -unsigned long thread_saved_pc(struct task_struct *tsk) -{ - return ((unsigned long *)tsk->thread.sp)[3]; -} - void __show_regs(struct pt_regs *regs, int all) { unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L; @@ -101,7 +90,7 @@ void __show_regs(struct pt_regs *regs, int all) cr0 = read_cr0(); cr2 = read_cr2(); cr3 = read_cr3(); - cr4 = __read_cr4_safe(); + cr4 = __read_cr4(); printk(KERN_DEFAULT "CR0: %08lx CR2: %08lx CR3: %08lx CR4: %08lx\n", cr0, cr2, cr3, cr4); @@ -133,35 +122,31 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long sp, unsigned long arg, struct task_struct *p, unsigned long tls) { struct pt_regs *childregs = task_pt_regs(p); + struct fork_frame *fork_frame = container_of(childregs, struct fork_frame, regs); + struct inactive_task_frame *frame = &fork_frame->frame; struct task_struct *tsk; int err; - p->thread.sp = (unsigned long) childregs; + frame->bp = 0; + frame->ret_addr = (unsigned long) ret_from_fork; + p->thread.sp = (unsigned long) fork_frame; p->thread.sp0 = (unsigned long) (childregs+1); memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps)); if (unlikely(p->flags & PF_KTHREAD)) { /* kernel thread */ memset(childregs, 0, sizeof(struct pt_regs)); - p->thread.ip = (unsigned long) ret_from_kernel_thread; - task_user_gs(p) = __KERNEL_STACK_CANARY; - childregs->ds = __USER_DS; - childregs->es = __USER_DS; - childregs->fs = __KERNEL_PERCPU; - childregs->bx = sp; /* function */ - childregs->bp = arg; - childregs->orig_ax = -1; - childregs->cs = __KERNEL_CS | get_kernel_rpl(); - childregs->flags = X86_EFLAGS_IF | X86_EFLAGS_FIXED; + frame->bx = sp; /* function */ + frame->di = arg; p->thread.io_bitmap_ptr = NULL; return 0; } + frame->bx = 0; *childregs = *current_pt_regs(); childregs->ax = 0; if (sp) childregs->sp = sp; - p->thread.ip = (unsigned long) ret_from_fork; task_user_gs(p) = get_user_gs(current_pt_regs()); p->thread.io_bitmap_ptr = NULL; diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 63236d8f84bf..de9acaf2d371 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -50,8 +50,6 @@ #include <asm/switch_to.h> #include <asm/xen/hypervisor.h> -asmlinkage extern void ret_from_fork(void); - __visible DEFINE_PER_CPU(unsigned long, rsp_scratch); /* Prints also some state that isn't saved in the pt_regs */ @@ -141,12 +139,17 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long sp, { int err; struct pt_regs *childregs; + struct fork_frame *fork_frame; + struct inactive_task_frame *frame; struct task_struct *me = current; p->thread.sp0 = (unsigned long)task_stack_page(p) + THREAD_SIZE; childregs = task_pt_regs(p); - p->thread.sp = (unsigned long) childregs; - set_tsk_thread_flag(p, TIF_FORK); + fork_frame = container_of(childregs, struct fork_frame, regs); + frame = &fork_frame->frame; + frame->bp = 0; + frame->ret_addr = (unsigned long) ret_from_fork; + p->thread.sp = (unsigned long) fork_frame; p->thread.io_bitmap_ptr = NULL; savesegment(gs, p->thread.gsindex); @@ -160,15 +163,11 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long sp, if (unlikely(p->flags & PF_KTHREAD)) { /* kernel thread */ memset(childregs, 0, sizeof(struct pt_regs)); - childregs->sp = (unsigned long)childregs; - childregs->ss = __KERNEL_DS; - childregs->bx = sp; /* function */ - childregs->bp = arg; - childregs->orig_ax = -1; - childregs->cs = __KERNEL_CS | get_kernel_rpl(); - childregs->flags = X86_EFLAGS_IF | X86_EFLAGS_FIXED; + frame->bx = sp; /* function */ + frame->r12 = arg; return 0; } + frame->bx = 0; *childregs = *current_pt_regs(); childregs->ax = 0; @@ -511,7 +510,7 @@ void set_personality_ia32(bool x32) current->personality &= ~READ_IMPLIES_EXEC; /* in_compat_syscall() uses the presence of the x32 syscall bit flag to determine compat status */ - current_thread_info()->status &= ~TS_COMPAT; + current->thread.status &= ~TS_COMPAT; } else { set_thread_flag(TIF_IA32); clear_thread_flag(TIF_X32); @@ -519,7 +518,7 @@ void set_personality_ia32(bool x32) current->mm->context.ia32_compat = TIF_IA32; current->personality |= force_personality32; /* Prepare the first "return" to user space */ - current_thread_info()->status |= TS_COMPAT; + current->thread.status |= TS_COMPAT; } } EXPORT_SYMBOL_GPL(set_personality_ia32); diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c index f79576a541ff..ce94c38cf4d6 100644 --- a/arch/x86/kernel/ptrace.c +++ b/arch/x86/kernel/ptrace.c @@ -173,8 +173,8 @@ unsigned long kernel_stack_pointer(struct pt_regs *regs) return sp; prev_esp = (u32 *)(context); - if (prev_esp) - return (unsigned long)prev_esp; + if (*prev_esp) + return (unsigned long)*prev_esp; return (unsigned long)regs; } @@ -934,7 +934,7 @@ static int putreg32(struct task_struct *child, unsigned regno, u32 value) */ regs->orig_ax = value; if (syscall_get_nr(child, regs) >= 0) - task_thread_info(child)->status |= TS_I386_REGS_POKED; + child->thread.status |= TS_I386_REGS_POKED; break; case offsetof(struct user32, regs.eflags): @@ -1250,7 +1250,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request, #ifdef CONFIG_X86_64 -static struct user_regset x86_64_regsets[] __read_mostly = { +static struct user_regset x86_64_regsets[] __ro_after_init = { [REGSET_GENERAL] = { .core_note_type = NT_PRSTATUS, .n = sizeof(struct user_regs_struct) / sizeof(long), @@ -1291,7 +1291,7 @@ static const struct user_regset_view user_x86_64_view = { #endif /* CONFIG_X86_64 */ #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION -static struct user_regset x86_32_regsets[] __read_mostly = { +static struct user_regset x86_32_regsets[] __ro_after_init = { [REGSET_GENERAL] = { .core_note_type = NT_PRSTATUS, .n = sizeof(struct user_regs_struct32) / sizeof(u32), @@ -1344,7 +1344,7 @@ static const struct user_regset_view user_x86_32_view = { */ u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS]; -void update_regset_xstate_info(unsigned int size, u64 xstate_mask) +void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask) { #ifdef CONFIG_X86_64 x86_64_regsets[REGSET_XSTATE].n = size / sizeof(u64); diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 63bf27d972b7..e244c19a2451 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -705,7 +705,7 @@ static void native_machine_power_off(void) tboot_shutdown(TB_SHUTDOWN_HALT); } -struct machine_ops machine_ops = { +struct machine_ops machine_ops __ro_after_init = { .power_off = native_machine_power_off, .shutdown = native_machine_shutdown, .emergency_restart = native_machine_emergency_restart, diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 2c4bc85dfe90..eeb094ea794a 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -210,9 +210,9 @@ EXPORT_SYMBOL(boot_cpu_data); #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64) -__visible unsigned long mmu_cr4_features; +__visible unsigned long mmu_cr4_features __ro_after_init; #else -__visible unsigned long mmu_cr4_features = X86_CR4_PAE; +__visible unsigned long mmu_cr4_features __ro_after_init = X86_CR4_PAE; #endif /* Boot loader ID and version as integers, for the benefit of proc_dointvec */ @@ -1137,7 +1137,7 @@ void __init setup_arch(char **cmdline_p) * auditing all the early-boot CR4 manipulation would be needed to * rule it out. */ - mmu_cr4_features = __read_cr4_safe(); + mmu_cr4_features = __read_cr4(); memblock_set_current_limit(get_max_mapped()); diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index 7a40e068302d..2bbd27f89802 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -33,7 +33,7 @@ EXPORT_PER_CPU_SYMBOL(cpu_number); DEFINE_PER_CPU_READ_MOSTLY(unsigned long, this_cpu_off) = BOOT_PERCPU_OFFSET; EXPORT_PER_CPU_SYMBOL(this_cpu_off); -unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = { +unsigned long __per_cpu_offset[NR_CPUS] __ro_after_init = { [0 ... NR_CPUS-1] = BOOT_PERCPU_OFFSET, }; EXPORT_SYMBOL(__per_cpu_offset); @@ -246,7 +246,7 @@ void __init setup_per_cpu_areas(void) #ifdef CONFIG_X86_64 per_cpu(irq_stack_ptr, cpu) = per_cpu(irq_stack_union.irq_stack, cpu) + - IRQ_STACK_SIZE - 64; + IRQ_STACK_SIZE; #endif #ifdef CONFIG_NUMA per_cpu(x86_cpu_to_node_map, cpu) = diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 04cb3212db2d..da20ecb5397a 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -783,7 +783,7 @@ static inline unsigned long get_nr_restart_syscall(const struct pt_regs *regs) * than the tracee. */ #ifdef CONFIG_IA32_EMULATION - if (current_thread_info()->status & (TS_COMPAT|TS_I386_REGS_POKED)) + if (current->thread.status & (TS_COMPAT|TS_I386_REGS_POKED)) return __NR_ia32_restart_syscall; #endif #ifdef CONFIG_X86_X32_ABI diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 54e2f1a968a4..7249dcf2cbcb 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -943,7 +943,6 @@ void common_cpu_up(unsigned int cpu, struct task_struct *idle) per_cpu(cpu_current_top_of_stack, cpu) = (unsigned long)task_stack_page(idle) + THREAD_SIZE; #else - clear_tsk_thread_flag(idle, TIF_FORK); initial_gs = per_cpu_offset(cpu); #endif } @@ -970,7 +969,7 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle) early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu); initial_code = (unsigned long)start_secondary; - stack_start = idle->thread.sp; + initial_stack = idle->thread.sp; /* * Enable the espfix hack for this CPU diff --git a/arch/x86/kernel/stacktrace.c b/arch/x86/kernel/stacktrace.c index 4738f5e0f2ab..0653788026e2 100644 --- a/arch/x86/kernel/stacktrace.c +++ b/arch/x86/kernel/stacktrace.c @@ -8,80 +8,69 @@ #include <linux/export.h> #include <linux/uaccess.h> #include <asm/stacktrace.h> +#include <asm/unwind.h> -static int save_stack_stack(void *data, char *name) +static int save_stack_address(struct stack_trace *trace, unsigned long addr, + bool nosched) { - return 0; -} - -static int -__save_stack_address(void *data, unsigned long addr, bool reliable, bool nosched) -{ - struct stack_trace *trace = data; -#ifdef CONFIG_FRAME_POINTER - if (!reliable) - return 0; -#endif if (nosched && in_sched_functions(addr)) return 0; + if (trace->skip > 0) { trace->skip--; return 0; } - if (trace->nr_entries < trace->max_entries) { - trace->entries[trace->nr_entries++] = addr; - return 0; - } else { - return -1; /* no more room, stop walking the stack */ - } -} -static int save_stack_address(void *data, unsigned long addr, int reliable) -{ - return __save_stack_address(data, addr, reliable, false); + if (trace->nr_entries >= trace->max_entries) + return -1; + + trace->entries[trace->nr_entries++] = addr; + return 0; } -static int -save_stack_address_nosched(void *data, unsigned long addr, int reliable) +static void __save_stack_trace(struct stack_trace *trace, + struct task_struct *task, struct pt_regs *regs, + bool nosched) { - return __save_stack_address(data, addr, reliable, true); -} + struct unwind_state state; + unsigned long addr; -static const struct stacktrace_ops save_stack_ops = { - .stack = save_stack_stack, - .address = save_stack_address, - .walk_stack = print_context_stack, -}; + if (regs) + save_stack_address(trace, regs->ip, nosched); -static const struct stacktrace_ops save_stack_ops_nosched = { - .stack = save_stack_stack, - .address = save_stack_address_nosched, - .walk_stack = print_context_stack, -}; + for (unwind_start(&state, task, regs, NULL); !unwind_done(&state); + unwind_next_frame(&state)) { + addr = unwind_get_return_address(&state); + if (!addr || save_stack_address(trace, addr, nosched)) + break; + } + + if (trace->nr_entries < trace->max_entries) + trace->entries[trace->nr_entries++] = ULONG_MAX; +} /* * Save stack-backtrace addresses into a stack_trace buffer. */ void save_stack_trace(struct stack_trace *trace) { - dump_trace(current, NULL, NULL, 0, &save_stack_ops, trace); - if (trace->nr_entries < trace->max_entries) - trace->entries[trace->nr_entries++] = ULONG_MAX; + __save_stack_trace(trace, current, NULL, false); } EXPORT_SYMBOL_GPL(save_stack_trace); void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace) { - dump_trace(current, regs, NULL, 0, &save_stack_ops, trace); - if (trace->nr_entries < trace->max_entries) - trace->entries[trace->nr_entries++] = ULONG_MAX; + __save_stack_trace(trace, current, regs, false); } void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) { - dump_trace(tsk, NULL, NULL, 0, &save_stack_ops_nosched, trace); - if (trace->nr_entries < trace->max_entries) - trace->entries[trace->nr_entries++] = ULONG_MAX; + if (!try_get_task_stack(tsk)) + return; + + __save_stack_trace(trace, tsk, NULL, true); + + put_task_stack(tsk); } EXPORT_SYMBOL_GPL(save_stack_trace_tsk); diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index b70ca12dd389..bd4e3d4d3625 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -292,12 +292,30 @@ DO_ERROR(X86_TRAP_NP, SIGBUS, "segment not present", segment_not_present) DO_ERROR(X86_TRAP_SS, SIGBUS, "stack segment", stack_segment) DO_ERROR(X86_TRAP_AC, SIGBUS, "alignment check", alignment_check) +#ifdef CONFIG_VMAP_STACK +__visible void __noreturn handle_stack_overflow(const char *message, + struct pt_regs *regs, + unsigned long fault_address) +{ + printk(KERN_EMERG "BUG: stack guard page was hit at %p (stack is %p..%p)\n", + (void *)fault_address, current->stack, + (char *)current->stack + THREAD_SIZE - 1); + die(message, regs, 0); + + /* Be absolutely certain we don't return. */ + panic(message); +} +#endif + #ifdef CONFIG_X86_64 /* Runs on IST stack */ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code) { static const char str[] = "double fault"; struct task_struct *tsk = current; +#ifdef CONFIG_VMAP_STACK + unsigned long cr2; +#endif #ifdef CONFIG_X86_ESPFIX64 extern unsigned char native_irq_return_iret[]; @@ -332,6 +350,49 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code) tsk->thread.error_code = error_code; tsk->thread.trap_nr = X86_TRAP_DF; +#ifdef CONFIG_VMAP_STACK + /* + * If we overflow the stack into a guard page, the CPU will fail + * to deliver #PF and will send #DF instead. Similarly, if we + * take any non-IST exception while too close to the bottom of + * the stack, the processor will get a page fault while + * delivering the exception and will generate a double fault. + * + * According to the SDM (footnote in 6.15 under "Interrupt 14 - + * Page-Fault Exception (#PF): + * + * Processors update CR2 whenever a page fault is detected. If a + * second page fault occurs while an earlier page fault is being + * deliv- ered, the faulting linear address of the second fault will + * overwrite the contents of CR2 (replacing the previous + * address). These updates to CR2 occur even if the page fault + * results in a double fault or occurs during the delivery of a + * double fault. + * + * The logic below has a small possibility of incorrectly diagnosing + * some errors as stack overflows. For example, if the IDT or GDT + * gets corrupted such that #GP delivery fails due to a bad descriptor + * causing #GP and we hit this condition while CR2 coincidentally + * points to the stack guard page, we'll think we overflowed the + * stack. Given that we're going to panic one way or another + * if this happens, this isn't necessarily worth fixing. + * + * If necessary, we could improve the test by only diagnosing + * a stack overflow if the saved RSP points within 47 bytes of + * the bottom of the stack: if RSP == tsk_stack + 48 and we + * take an exception, the stack is already aligned and there + * will be enough room SS, RSP, RFLAGS, CS, RIP, and a + * possible error code, so a stack overflow would *not* double + * fault. With any less space left, exception delivery could + * fail, and, as a practical matter, we've overflowed the + * stack even if the actual trigger for the double fault was + * something else. + */ + cr2 = read_cr2(); + if ((unsigned long)task_stack_page(tsk) - 1 - cr2 < PAGE_SIZE) + handle_stack_overflow("kernel stack overflow (double-fault)", regs, cr2); +#endif + #ifdef CONFIG_DOUBLEFAULT df_debug(regs, error_code); #endif diff --git a/arch/x86/kernel/unwind_frame.c b/arch/x86/kernel/unwind_frame.c new file mode 100644 index 000000000000..a2456d4d286a --- /dev/null +++ b/arch/x86/kernel/unwind_frame.c @@ -0,0 +1,93 @@ +#include <linux/sched.h> +#include <asm/ptrace.h> +#include <asm/bitops.h> +#include <asm/stacktrace.h> +#include <asm/unwind.h> + +#define FRAME_HEADER_SIZE (sizeof(long) * 2) + +unsigned long unwind_get_return_address(struct unwind_state *state) +{ + unsigned long addr; + unsigned long *addr_p = unwind_get_return_address_ptr(state); + + if (unwind_done(state)) + return 0; + + addr = ftrace_graph_ret_addr(state->task, &state->graph_idx, *addr_p, + addr_p); + + return __kernel_text_address(addr) ? addr : 0; +} +EXPORT_SYMBOL_GPL(unwind_get_return_address); + +static bool update_stack_state(struct unwind_state *state, void *addr, + size_t len) +{ + struct stack_info *info = &state->stack_info; + + /* + * If addr isn't on the current stack, switch to the next one. + * + * We may have to traverse multiple stacks to deal with the possibility + * that 'info->next_sp' could point to an empty stack and 'addr' could + * be on a subsequent stack. + */ + while (!on_stack(info, addr, len)) + if (get_stack_info(info->next_sp, state->task, info, + &state->stack_mask)) + return false; + + return true; +} + +bool unwind_next_frame(struct unwind_state *state) +{ + unsigned long *next_bp; + + if (unwind_done(state)) + return false; + + next_bp = (unsigned long *)*state->bp; + + /* make sure the next frame's data is accessible */ + if (!update_stack_state(state, next_bp, FRAME_HEADER_SIZE)) + return false; + + /* move to the next frame */ + state->bp = next_bp; + return true; +} +EXPORT_SYMBOL_GPL(unwind_next_frame); + +void __unwind_start(struct unwind_state *state, struct task_struct *task, + struct pt_regs *regs, unsigned long *first_frame) +{ + memset(state, 0, sizeof(*state)); + state->task = task; + + /* don't even attempt to start from user mode regs */ + if (regs && user_mode(regs)) { + state->stack_info.type = STACK_TYPE_UNKNOWN; + return; + } + + /* set up the starting stack frame */ + state->bp = get_frame_pointer(task, regs); + + /* initialize stack info and make sure the frame data is accessible */ + get_stack_info(state->bp, state->task, &state->stack_info, + &state->stack_mask); + update_stack_state(state, state->bp, FRAME_HEADER_SIZE); + + /* + * The caller can provide the address of the first frame directly + * (first_frame) or indirectly (regs->sp) to indicate which stack frame + * to start unwinding at. Skip ahead until we reach it. + */ + while (!unwind_done(state) && + (!on_stack(&state->stack_info, first_frame, sizeof(long)) || + state->bp < first_frame)) + unwind_next_frame(state); +} +EXPORT_SYMBOL_GPL(__unwind_start); diff --git a/arch/x86/kernel/unwind_guess.c b/arch/x86/kernel/unwind_guess.c new file mode 100644 index 000000000000..b5a834c93065 --- /dev/null +++ b/arch/x86/kernel/unwind_guess.c @@ -0,0 +1,43 @@ +#include <linux/sched.h> +#include <linux/ftrace.h> +#include <asm/ptrace.h> +#include <asm/bitops.h> +#include <asm/stacktrace.h> +#include <asm/unwind.h> + +bool unwind_next_frame(struct unwind_state *state) +{ + struct stack_info *info = &state->stack_info; + + if (unwind_done(state)) + return false; + + do { + for (state->sp++; state->sp < info->end; state->sp++) + if (__kernel_text_address(*state->sp)) + return true; + + state->sp = info->next_sp; + + } while (!get_stack_info(state->sp, state->task, info, + &state->stack_mask)); + + return false; +} +EXPORT_SYMBOL_GPL(unwind_next_frame); + +void __unwind_start(struct unwind_state *state, struct task_struct *task, + struct pt_regs *regs, unsigned long *first_frame) +{ + memset(state, 0, sizeof(*state)); + + state->task = task; + state->sp = first_frame; + + get_stack_info(first_frame, state->task, &state->stack_info, + &state->stack_mask); + + if (!__kernel_text_address(*first_frame)) + unwind_next_frame(state); +} +EXPORT_SYMBOL_GPL(__unwind_start); diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c index 76c5e52436c4..0bd9f1287f39 100644 --- a/arch/x86/kernel/x86_init.c +++ b/arch/x86/kernel/x86_init.c @@ -91,7 +91,7 @@ struct x86_cpuinit_ops x86_cpuinit = { static void default_nmi_init(void) { }; static int default_i8042_detect(void) { return 1; }; -struct x86_platform_ops x86_platform = { +struct x86_platform_ops x86_platform __ro_after_init = { .calibrate_cpu = native_calibrate_cpu, .calibrate_tsc = native_calibrate_tsc, .get_wallclock = mach_get_cmos_time, @@ -108,7 +108,7 @@ struct x86_platform_ops x86_platform = { EXPORT_SYMBOL_GPL(x86_platform); #if defined(CONFIG_PCI_MSI) -struct x86_msi_ops x86_msi = { +struct x86_msi_ops x86_msi __ro_after_init = { .setup_msi_irqs = native_setup_msi_irqs, .teardown_msi_irq = native_teardown_msi_irq, .teardown_msi_irqs = default_teardown_msi_irqs, @@ -137,7 +137,7 @@ void arch_restore_msi_irqs(struct pci_dev *dev) } #endif -struct x86_io_apic_ops x86_io_apic_ops = { +struct x86_io_apic_ops x86_io_apic_ops __ro_after_init = { .read = native_io_apic_read, .disable = native_disable_io_apic, }; |