x86/stacktrace: Do not fail for ORC with regs on stack

save_stack_trace_reliable now returns "non reliable" when there are
kernel pt_regs on stack. This means an interrupt or exception happened
somewhere down the route. It is a problem for the frame pointer
unwinder, because the frame might not have been set up yet when the irq
happened, so the unwinder might fail to unwind from the interrupted
function.

With ORC, this is not a problem, as ORC has out-of-band data. We can
find ORC data even for the IP in the interrupted function and always
unwind one level up reliably.

So lift the check to apply only when CONFIG_FRAME_POINTER=y is enabled.

Signed-off-by: Jiri Slaby <[email protected]>
Acked-by: Josh Poimboeuf <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: https://lkml.kernel.org/lkml/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

0 files changed, 0 insertions, 0 deletions