From 4b8afafbe743be1a81c96ddcd75b19c534d5e262 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 24 Aug 2016 11:50:17 -0500 Subject: x86/dumpstack: Add get_stack_pointer() and get_frame_pointer() The various functions involved in dumping the stack all do similar things with regard to getting the stack pointer and the frame pointer based on the regs and task arguments. Create helper functions to do that instead. Signed-off-by: Josh Poimboeuf Reviewed-by: Andy Lutomirski Cc: Andy Lutomirski Cc: Brian Gerst Cc: Byungchul Park Cc: Frederic Weisbecker Cc: Kees Cook Cc: Linus Torvalds Cc: Nilay Vaish Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/f448914885a35f333fe04da1b97a6c2cc1f80974.1472057064.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/dumpstack_32.c | 25 ++++--------------------- 1 file changed, 4 insertions(+), 21 deletions(-) (limited to 'arch/x86/kernel/dumpstack_32.c') diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index 09675712eba8..358fe1cd4e5b 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -46,19 +46,9 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs, int graph = 0; u32 *prev_esp; - if (!task) - task = current; - - if (!stack) { - unsigned long dummy; - - stack = &dummy; - if (task != current) - stack = (unsigned long *)task->thread.sp; - } - - if (!bp) - bp = stack_frame(task, regs); + task = task ? : current; + stack = stack ? : get_stack_pointer(task, regs); + bp = bp ? : (unsigned long)get_frame_pointer(task, regs); for (;;) { void *end_stack; @@ -95,14 +85,7 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, 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; - } + sp = sp ? : get_stack_pointer(task, regs); stack = sp; for (i = 0; i < kstack_depth_to_print; i++) { -- cgit v1.2.3 From 5a8ff54c260ecfed3de9b8d1272eb87826935df8 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 24 Aug 2016 11:50:18 -0500 Subject: x86/dumpstack: Remove unnecessary stack pointer arguments When calling show_stack_log_lvl() or dump_trace() with a regs argument, providing a stack pointer or frame pointer is redundant. Signed-off-by: Josh Poimboeuf d Reviewed-by: Andy Lutomirski Cc: Andy Lutomirski Cc: Brian Gerst Cc: Byungchul Park Cc: Frederic Weisbecker Cc: Kees Cook Cc: Linus Torvalds Cc: Nilay Vaish Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1694e2e955e3b9a73a3c3d5ba2634344014dd550.1472057064.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/dumpstack_32.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/kernel/dumpstack_32.c') diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index 358fe1cd4e5b..c533b8b5a373 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -122,7 +122,7 @@ 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(NULL, regs, NULL, 0, KERN_EMERG); pr_emerg("Code:"); -- cgit v1.2.3 From cfeeed279dc2fa83a00fbe4856ebd231d56201ab Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 8 Sep 2016 16:49:20 -0500 Subject: x86/dumpstack: Allow preemption in show_stack_log_lvl() and dump_trace() show_stack_log_lvl() and dump_trace() are already preemption safe: - If they're running in irq or exception context, preemption is already disabled and the percpu stack pointers can be trusted. - If they're running with preemption enabled, they must be running on the task stack anyway, so it doesn't matter if they're comparing the stack pointer against a percpu stack pointer from this CPU or another one: either way it won't match. Signed-off-by: Josh Poimboeuf Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Byungchul Park Cc: Denys Vlasenko Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kees Cook Cc: Linus Torvalds Cc: Nilay Vaish Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/a0ca0b1044eca97d4f0ec7c1619cf80b3b65560d.1473371307.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/dumpstack_32.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) (limited to 'arch/x86/kernel/dumpstack_32.c') diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index c533b8b5a373..da5cd62f93ab 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -24,16 +24,16 @@ static void *is_irq_stack(void *p, void *irq) } -static void *is_hardirq_stack(unsigned long *stack, int cpu) +static void *is_hardirq_stack(unsigned long *stack) { - void *irq = per_cpu(hardirq_stack, cpu); + void *irq = this_cpu_read(hardirq_stack); return is_irq_stack(stack, irq); } -static void *is_softirq_stack(unsigned long *stack, int cpu) +static void *is_softirq_stack(unsigned long *stack) { - void *irq = per_cpu(softirq_stack, cpu); + void *irq = this_cpu_read(softirq_stack); return is_irq_stack(stack, irq); } @@ -42,7 +42,6 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs, unsigned long *stack, unsigned long bp, const struct stacktrace_ops *ops, void *data) { - const unsigned cpu = get_cpu(); int graph = 0; u32 *prev_esp; @@ -53,9 +52,9 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs, for (;;) { void *end_stack; - end_stack = is_hardirq_stack(stack, cpu); + end_stack = is_hardirq_stack(stack); if (!end_stack) - end_stack = is_softirq_stack(stack, cpu); + end_stack = is_softirq_stack(stack); bp = ops->walk_stack(task, stack, bp, ops, data, end_stack, &graph); @@ -74,7 +73,6 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs, break; touch_nmi_watchdog(); } - put_cpu(); } EXPORT_SYMBOL(dump_trace); -- cgit v1.2.3 From cb76c93982404273d746f3ccd5085b47689099a8 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 14 Sep 2016 21:07:42 -0500 Subject: x86/dumpstack: Add get_stack_info() interface valid_stack_ptr() is buggy: it assumes that all stacks are of size THREAD_SIZE, which is not true for exception stacks. So the walk_stack() callbacks will need to know the location of the beginning of the stack as well as the end. Another issue is that in general the various features of a stack (type, size, next stack pointer, description string) are scattered around in various places throughout the stack dump code. Encapsulate all that information in a single place with a new stack_info struct and a get_stack_info() interface. Signed-off-by: Josh Poimboeuf Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Byungchul Park Cc: Denys Vlasenko Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kees Cook Cc: Linus Torvalds Cc: Nilay Vaish Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/8164dd0db96b7e6a279fa17ae5e6dc375eecb4a9.1473905218.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/dumpstack_32.c | 106 +++++++++++++++++++++++++++++++---------- 1 file changed, 81 insertions(+), 25 deletions(-) (limited to 'arch/x86/kernel/dumpstack_32.c') diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index da5cd62f93ab..c92da5a4d663 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -16,61 +16,117 @@ #include -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 bool in_hardirq_stack(unsigned long *stack, struct stack_info *info) +{ + unsigned long *begin = (unsigned long *)this_cpu_read(hardirq_stack); + unsigned long *end = begin + (THREAD_SIZE / sizeof(long)); + + if (stack < begin || stack >= end) + return false; + + info->type = STACK_TYPE_IRQ; + info->begin = begin; + info->end = end; + + /* + * See irq_32.c -- the next stack pointer is stored at the beginning of + * the stack. + */ + info->next_sp = (unsigned long *)*begin; + + return true; +} -static void *is_hardirq_stack(unsigned long *stack) +static bool in_softirq_stack(unsigned long *stack, struct stack_info *info) { - void *irq = this_cpu_read(hardirq_stack); + unsigned long *begin = (unsigned long *)this_cpu_read(softirq_stack); + unsigned long *end = begin + (THREAD_SIZE / sizeof(long)); + + if (stack < begin || stack >= end) + return false; + + info->type = STACK_TYPE_SOFTIRQ; + info->begin = begin; + info->end = end; + + /* + * The next stack pointer is stored at the beginning of the stack. + * See irq_32.c. + */ + info->next_sp = (unsigned long *)*begin; - return is_irq_stack(stack, irq); + return true; } -static void *is_softirq_stack(unsigned long *stack) +int get_stack_info(unsigned long *stack, struct task_struct *task, + struct stack_info *info, unsigned long *visit_mask) { - void *irq = this_cpu_read(softirq_stack); + if (!stack) + goto unknown; - return is_irq_stack(stack, irq); + task = task ? : current; + + if (in_task_stack(stack, task, info)) + return 0; + + if (task != current) + goto unknown; + + if (in_hardirq_stack(stack, info)) + return 0; + + if (in_softirq_stack(stack, info)) + return 0; + +unknown: + info->type = STACK_TYPE_UNKNOWN; + return -EINVAL; } void dump_trace(struct task_struct *task, struct pt_regs *regs, unsigned long *stack, unsigned long bp, const struct stacktrace_ops *ops, void *data) { + unsigned long visit_mask = 0; int graph = 0; - u32 *prev_esp; task = task ? : current; stack = stack ? : get_stack_pointer(task, regs); bp = bp ? : (unsigned long)get_frame_pointer(task, regs); for (;;) { - void *end_stack; + const char *begin_str, *end_str; + struct stack_info info; - end_stack = is_hardirq_stack(stack); - if (!end_stack) - end_stack = is_softirq_stack(stack); + if (get_stack_info(stack, task, &info, &visit_mask)) + break; - bp = ops->walk_stack(task, stack, bp, ops, data, - end_stack, &graph); + stack_type_str(info.type, &begin_str, &end_str); - /* Stop if not on irq stack */ - if (!end_stack) + if (begin_str && ops->stack(data, begin_str) < 0) break; - /* 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; + bp = ops->walk_stack(task, stack, bp, ops, data, &info, &graph); - if (ops->stack(data, "IRQ") < 0) + if (end_str && ops->stack(data, end_str) < 0) break; + + stack = info.next_sp; + touch_nmi_watchdog(); } } -- cgit v1.2.3 From 5fe599e02e41550c59831613a11c8ae057897c29 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 14 Sep 2016 21:07:43 -0500 Subject: x86/dumpstack: Add support for unwinding empty IRQ stacks When an interrupt happens in entry code while running on a software IRQ stack, and the IRQ stack was empty, regs->sp will contain the stack end address (e.g., irq_stack_ptr). If the regs are passed to dump_trace(), get_stack_info() will report STACK_TYPE_UNKNOWN, causing dump_trace() to return prematurely without trying to go to the next stack. Update the bounds checking for software interrupt stacks so that the ending address is now considered part of the stack. This means that it's now possible for the 'walk_stack' callbacks -- print_context_stack() and print_context_stack_bp() -- to be called with an empty stack. But that's fine; they're already prepared to deal with that due to their on_stack() checks. Signed-off-by: Josh Poimboeuf Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Byungchul Park Cc: Denys Vlasenko Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kees Cook Cc: Linus Torvalds Cc: Nilay Vaish Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/5a5e5de92dcf11e8dc6b6e8e50ad7639d067830b.1473905218.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/dumpstack_32.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'arch/x86/kernel/dumpstack_32.c') diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index c92da5a4d663..50076d4366c4 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -35,7 +35,11 @@ static bool in_hardirq_stack(unsigned long *stack, struct stack_info *info) unsigned long *begin = (unsigned long *)this_cpu_read(hardirq_stack); unsigned long *end = begin + (THREAD_SIZE / sizeof(long)); - if (stack < begin || stack >= end) + /* + * 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; info->type = STACK_TYPE_IRQ; @@ -56,7 +60,11 @@ static bool in_softirq_stack(unsigned long *stack, struct stack_info *info) unsigned long *begin = (unsigned long *)this_cpu_read(softirq_stack); unsigned long *end = begin + (THREAD_SIZE / sizeof(long)); - if (stack < begin || stack >= end) + /* + * 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; info->type = STACK_TYPE_SOFTIRQ; -- cgit v1.2.3 From fcd709ef20a9d83bdb7524d27cd6719dac8690a0 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 14 Sep 2016 21:07:44 -0500 Subject: x86/dumpstack: Add recursion checking for all stacks in_exception_stack() has some recursion checking which makes sure the stack trace code never traverses a given exception stack more than once. This prevents an infinite loop if corruption somehow causes a stack's "next stack" pointer to point to itself (directly or indirectly). The recursion checking can be useful for other stacks in addition to the exception stack, so extend it to work for all stacks. Signed-off-by: Josh Poimboeuf Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Byungchul Park Cc: Denys Vlasenko Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kees Cook Cc: Linus Torvalds Cc: Nilay Vaish Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/95de5db4cfe111754845a5cef04e20630d01423f.1473905218.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/dumpstack_32.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) (limited to 'arch/x86/kernel/dumpstack_32.c') diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index 50076d4366c4..2d65cfa5e0b4 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -89,16 +89,32 @@ int get_stack_info(unsigned long *stack, struct task_struct *task, task = task ? : current; if (in_task_stack(stack, task, info)) - return 0; + goto recursion_check; if (task != current) goto unknown; if (in_hardirq_stack(stack, info)) - return 0; + goto recursion_check; if (in_softirq_stack(stack, info)) - return 0; + 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; + } + + return 0; unknown: info->type = STACK_TYPE_UNKNOWN; -- cgit v1.2.3 From 1959a60182f48879635812a03a99c02231ea8677 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Thu, 15 Sep 2016 22:45:45 -0700 Subject: x86/dumpstack: Pin the target stack when dumping it Specifically, pin the stack in save_stack_trace_tsk() and show_trace_log_lvl(). This will prevent a crash if the target task dies before or while dumping its stack once we start freeing task stacks early. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jann Horn Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/cf0082cde65d1941a996d026f2b2cdbfaca17bfa.1474003868.git.luto@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/kernel/dumpstack_32.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/x86/kernel/dumpstack_32.c') diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index 2d65cfa5e0b4..122f37d7bb7e 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -163,6 +163,9 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, unsigned long *stack; int i; + if (!try_get_task_stack(task)) + return; + sp = sp ? : get_stack_pointer(task, regs); stack = sp; @@ -179,6 +182,8 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, } pr_cont("\n"); show_trace_log_lvl(task, regs, sp, bp, log_lvl); + + put_task_stack(task); } -- cgit v1.2.3 From 81539169f283329fd8bc58457cc15754f683ba69 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Fri, 16 Sep 2016 08:05:20 -0500 Subject: x86/dumpstack: Remove NULL task pointer convention show_stack_log_lvl() and friends allow a NULL pointer for the task_struct to indicate the current task. This creates confusion and can cause sneaky bugs. Instead require the caller to pass 'current' directly. This only changes the internal workings of the dumpstack code. The dump_trace() and show_stack() interfaces still allow a NULL task pointer. Those interfaces should also probably be fixed as well. Signed-off-by: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Ingo Molnar --- arch/x86/kernel/dumpstack_32.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/kernel/dumpstack_32.c') diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index 122f37d7bb7e..4ff000811e03 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -205,7 +205,7 @@ void show_regs(struct pt_regs *regs) u8 *ip; pr_emerg("Stack:\n"); - show_stack_log_lvl(NULL, regs, NULL, 0, KERN_EMERG); + show_stack_log_lvl(current, regs, NULL, 0, KERN_EMERG); pr_emerg("Code:"); -- cgit v1.2.3 From e18bcccd1a4ecb41e99678e002ef833586185bf1 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Fri, 16 Sep 2016 14:18:16 -0500 Subject: x86/dumpstack: Convert show_trace_log_lvl() to use the new unwinder Convert show_trace_log_lvl() to use the new unwinder. dump_trace() has been deprecated. show_trace_log_lvl() is special compared to other users of the unwinder. It's the only place where both reliable *and* unreliable addresses are needed. With frame pointers enabled, most callers of the unwinder don't want to know about unreliable addresses. But in this case, when we're dumping the stack to the console because something presumably went wrong, the unreliable addresses are useful: - They show stale data on the stack which can provide useful clues. - If something goes wrong with the unwinder, or if frame pointers are corrupt or missing, all the stack addresses still get shown. So in order to show all addresses on the stack, and at the same time figure out which addresses are reliable, we have to do the scanning and the unwinding in parallel. The scanning is done with the help of get_stack_info() to traverse the stacks. The unwinding is done separately by the new unwinder. In theory we could simplify show_trace_log_lvl() by instead pushing some of this logic into the unwind code. But then we would need some kind of "fake" frame logic in the unwinder which would add a lot of complexity and wouldn't be worth it in order to support only one user. Another benefit of this approach is that once we have a DWARF unwinder, we should be able to just plug it in with minimal impact to this code. Another change here is that callers of show_trace_log_lvl() don't need to provide the 'bp' argument. The unwinder already finds the relevant frame pointer by unwinding until it reaches the first frame after the provided stack pointer. Signed-off-by: Josh Poimboeuf Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Byungchul Park Cc: Denys Vlasenko Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kees Cook Cc: Linus Torvalds Cc: Nilay Vaish Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/703b5998604c712a1f801874b43f35d6dac52ede.1474045023.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/dumpstack_32.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'arch/x86/kernel/dumpstack_32.c') diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index 4ff000811e03..e476eb774278 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -156,9 +156,8 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs, } 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; @@ -181,7 +180,7 @@ 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); } @@ -205,7 +204,7 @@ void show_regs(struct pt_regs *regs) u8 *ip; pr_emerg("Stack:\n"); - show_stack_log_lvl(current, regs, NULL, 0, KERN_EMERG); + show_stack_log_lvl(current, regs, NULL, KERN_EMERG); pr_emerg("Code:"); -- cgit v1.2.3 From c8fe4609827aedc9c4b45de80e7cdc8ccfa8541b Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Fri, 16 Sep 2016 14:18:17 -0500 Subject: x86/dumpstack: Remove dump_trace() and related callbacks All previous users of dump_trace() have been converted to use the new unwind interfaces, so we can remove it and the related print_context_stack() and print_context_stack_bp() callback functions. Signed-off-by: Josh Poimboeuf Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Byungchul Park Cc: Denys Vlasenko Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kees Cook Cc: Linus Torvalds Cc: Nilay Vaish Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/5b97da3572b40b5a4d8e185cf2429308d0987a13.1474045023.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/dumpstack_32.c | 35 ----------------------------------- 1 file changed, 35 deletions(-) (limited to 'arch/x86/kernel/dumpstack_32.c') diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index e476eb774278..06eb322b5f9f 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -121,41 +121,6 @@ unknown: return -EINVAL; } -void dump_trace(struct task_struct *task, struct pt_regs *regs, - unsigned long *stack, unsigned long bp, - const struct stacktrace_ops *ops, void *data) -{ - unsigned long visit_mask = 0; - int graph = 0; - - task = task ? : current; - stack = stack ? : get_stack_pointer(task, regs); - bp = bp ? : (unsigned long)get_frame_pointer(task, regs); - - for (;;) { - const char *begin_str, *end_str; - struct stack_info info; - - if (get_stack_info(stack, task, &info, &visit_mask)) - break; - - stack_type_str(info.type, &begin_str, &end_str); - - if (begin_str && ops->stack(data, begin_str) < 0) - break; - - bp = ops->walk_stack(task, stack, bp, ops, data, &info, &graph); - - if (end_str && ops->stack(data, end_str) < 0) - break; - - stack = info.next_sp; - - touch_nmi_watchdog(); - } -} -EXPORT_SYMBOL(dump_trace); - void show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, unsigned long *sp, char *log_lvl) { -- cgit v1.2.3