Commit 9f12cea9 authored Sep 26, 2016 by Mark Rutland Committed by Greg Kroah-Hartman Sep 27, 2016

drivers/tty: Explicitly pass current to show_stack



As noted in commit:

  81539169 ("x86/dumpstack: Remove NULL task pointer convention")

... having a NULL task parameter imply current leads to subtle bugs in stack
walking code (so far seen on both 86 and arm64), makes callsites harder to
read, and is unnecessary as all callers have access to current.

As a step towards removing the problematic NULL-implies-current idiom entirely,
have the sysrq code explicitly pass current to show_stack.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 4b75f800

drivers/tty/sysrq.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -224,7 +224,7 @@ static void showacpu(void *dummy)

		spin_lock_irqsave(&show_lock, flags);
		pr_info("CPU%d:\n", smp_processor_id());
		show_stack(NULL, NULL);
		show_stack(current, NULL);
		spin_unlock_irqrestore(&show_lock, flags);
		}

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