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.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'arch/x86/kernel/dumpstack.c') diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c index aa208e565b03..e0648f755158 100644 --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -175,11 +175,13 @@ void show_stack(struct task_struct *task, unsigned long *sp) { unsigned long bp = 0; + task = task ? : current; + /* * Stack frames below this one aren't interesting. Don't show them * if we're printing for %current. */ - if (!sp && (!task || task == current)) { + if (!sp && task == current) { sp = get_stack_pointer(current, NULL); bp = (unsigned long)get_frame_pointer(current, NULL); } -- cgit v1.2.3