On 8/1/2025 2:36 PM, Heiko Carstens wrote:

On Thu, Jul 17, 2025 at 10:19:54PM -0700, Josh Poimboeuf wrote:

quoted

On Thu, Jul 17, 2025 at 02:20:12PM +0200, Jens Remus wrote:

quoted

I believe stack_trace_save_user() is only used by ftrace, and that will
no longer be needed once ftrace starts using unwind_user.

Maybe Heiko knows if that backchain user stacktrace code has any users?

If distros aren't building with -mbackchain, maybe backchain support can
be considered obsoleted by sframe, and we can get away with not
implementing it.

I guess that's a valid option. I know only of some special cases where
users compile everything on their own with -mbackchain to make this
work on a per-case basis. It shouldn't cause to much pain for them to
switch to sframe, as soon as that is available.

Let me have another stab at a cleaner implementation.  Shouldn't be too
much effort.  We can then decide whether to leave it out or not.

Will be away from keyboard for a few weeks.

Regards,
Jens
-- 
Jens Remus
Linux on Z Development (D3303)
+49-7031-16-1128 Office
jremus@de.ibm.com

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