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authorCatalin Marinas <catalin.marinas@arm.com>2017-08-09 15:37:49 +0100
committerCatalin Marinas <catalin.marinas@arm.com>2017-08-09 15:37:49 +0100
commit0553896787353e2526078064ff1cf21ff7bc34ce (patch)
treebf9f6490d4a74991653da4054cfc4c1b7c647074 /arch/arm64/kernel/traps.c
parent739586951b8abe381a98797a5e27a0a9336333d6 (diff)
parent31e43ad3b74a5d7b282023b72f25fc677c14c727 (diff)
Merge branch 'arm64/exception-stack' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux into for-next/core
* 'arm64/exception-stack' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux: arm64: unwind: remove sp from struct stackframe arm64: unwind: reference pt_regs via embedded stack frame arm64: unwind: disregard frame.sp when validating frame pointer arm64: unwind: avoid percpu indirection for irq stack arm64: move non-entry code out of .entry.text arm64: consistently use bl for C exception entry arm64: Add ASM_BUG()
Diffstat (limited to 'arch/arm64/kernel/traps.c')
-rw-r--r--arch/arm64/kernel/traps.c34
1 files changed, 7 insertions, 27 deletions
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index ccb9727d67b2..9f023d128c8c 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -143,7 +143,6 @@ static void dump_instr(const char *lvl, struct pt_regs *regs)
void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
{
struct stackframe frame;
- unsigned long irq_stack_ptr;
int skip;
pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
@@ -154,25 +153,14 @@ void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
if (!try_get_task_stack(tsk))
return;
- /*
- * Switching between stacks is valid when tracing current and in
- * non-preemptible context.
- */
- if (tsk == current && !preemptible())
- irq_stack_ptr = IRQ_STACK_PTR(smp_processor_id());
- else
- irq_stack_ptr = 0;
-
if (tsk == current) {
frame.fp = (unsigned long)__builtin_frame_address(0);
- frame.sp = current_stack_pointer;
frame.pc = (unsigned long)dump_backtrace;
} else {
/*
* task blocked in __switch_to
*/
frame.fp = thread_saved_fp(tsk);
- frame.sp = thread_saved_sp(tsk);
frame.pc = thread_saved_pc(tsk);
}
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
@@ -182,13 +170,12 @@ void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
skip = !!regs;
printk("Call trace:\n");
while (1) {
- unsigned long where = frame.pc;
unsigned long stack;
int ret;
/* skip until specified stack frame */
if (!skip) {
- dump_backtrace_entry(where);
+ dump_backtrace_entry(frame.pc);
} else if (frame.fp == regs->regs[29]) {
skip = 0;
/*
@@ -203,20 +190,13 @@ void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
ret = unwind_frame(tsk, &frame);
if (ret < 0)
break;
- stack = frame.sp;
- if (in_exception_text(where)) {
- /*
- * If we switched to the irq_stack before calling this
- * exception handler, then the pt_regs will be on the
- * task stack. The easiest way to tell is if the large
- * pt_regs would overlap with the end of the irq_stack.
- */
- if (stack < irq_stack_ptr &&
- (stack + sizeof(struct pt_regs)) > irq_stack_ptr)
- stack = IRQ_STACK_TO_TASK_STACK(irq_stack_ptr);
+ if (in_entry_text(frame.pc)) {
+ stack = frame.fp - offsetof(struct pt_regs, stackframe);
- dump_mem("", "Exception stack", stack,
- stack + sizeof(struct pt_regs));
+ if (on_task_stack(tsk, stack) ||
+ (tsk == current && !preemptible() && on_irq_stack(stack)))
+ dump_mem("", "Exception stack", stack,
+ stack + sizeof(struct pt_regs));
}
}