x86/stacktrace: Remove STACKTRACE_DUMP_ONCE (17426923) · Commits · 戴 / test

The stack unwinding can sometimes fail yet. Especially with the generated debug info. So do not yell at users -- live patching (the only user of this interface) will inform the user about the failure gracefully. And given this was the only user of the macro, remove the macro proper too. Signed-off-by:

Jiri Slaby <jslaby@suse.cz> Acked-by:

Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/lkml/20180518064713.26440-2-jslaby@suse.cz Signed-off-by:

Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/stacktrace.c

+2 −16

Original line number	Diff line number	Diff line
		@@ -81,16 +81,6 @@ EXPORT_SYMBOL_GPL(save_stack_trace_tsk);

		#ifdef CONFIG_HAVE_RELIABLE_STACKTRACE

		#define STACKTRACE_DUMP_ONCE(task) ({ \
		static bool __section(.data.unlikely) __dumped; \
		\
		if (!__dumped) { \
		__dumped = true; \
		WARN_ON(1); \
		show_stack(task, NULL); \
		} \
		})

		static int __always_inline
		__save_stack_trace_reliable(struct stack_trace *trace,
		struct task_struct *task)
		@@ -123,20 +113,16 @@ __save_stack_trace_reliable(struct stack_trace *trace,
		* generated code which __kernel_text_address() doesn't know
		* about.
		*/
		if (!addr) {
		STACKTRACE_DUMP_ONCE(task);
		if (!addr)
		return -EINVAL;
		}

		if (save_stack_address(trace, addr, false))
		return -EINVAL;
		}

		/* Check for stack corruption */
		if (unwind_error(&state)) {
		STACKTRACE_DUMP_ONCE(task);
		if (unwind_error(&state))
		return -EINVAL;
		}

		if (trace->nr_entries < trace->max_entries)
		trace->entries[trace->nr_entries++] = ULONG_MAX;

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