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arm64: stacktrace: fix the usage of ftrace_graph_ret_addr()

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ftrace_graph_ret_addr() takes an 'idx' integer pointer that is used to
optimize the stack unwinding process. arm64 currently passes `NULL` for
this parameter which stops it from utilizing these optimizations.

Further, the current code for ftrace_graph_ret_addr() will just return
the passed in return address if it is NULL which will break this usage.

Pass a valid integer pointer to ftrace_graph_ret_addr() similar to
x86_64's stack unwinder.

Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Fixes: 29c1c24a27 ("function_graph: Fix up ftrace_graph_ret_addr()")
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20240618162342.28275-1-puranjay@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Puranjay Mohan 2024-06-18 16:23:42 +00:00 committed by Catalin Marinas
parent 75c8f387dd
commit c060f93253
1 changed files with 3 additions and 1 deletions
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4
arch/arm64/kernel/stacktrace.c
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@ -25,6 +25,7 @@
*
* @common: Common unwind state.
* @task: The task being unwound.
* @graph_idx: Used by ftrace_graph_ret_addr() for optimized stack unwinding.
* @kr_cur: When KRETPROBES is selected, holds the kretprobe instance
* associated with the most recently encountered replacement lr
* value.
@ -32,6 +33,7 @@
struct kunwind_state {
struct unwind_state common;
struct task_struct *task;
int graph_idx;
#ifdef CONFIG_KRETPROBES
struct llist_node *kr_cur;
#endif
@ -106,7 +108,7 @@ kunwind_recover_return_address(struct kunwind_state *state)
if (state->task->ret_stack &&
(state->common.pc == (unsigned long)return_to_handler)) {
unsigned long orig_pc;
orig_pc = ftrace_graph_ret_addr(state->task, NULL,
orig_pc = ftrace_graph_ret_addr(state->task, &state->graph_idx,
state->common.pc,
(void *)state->common.fp);
if (WARN_ON_ONCE(state->common.pc == orig_pc))