Le 14/12/2021 à 07:09, Christophe Leroy a écrit :

Le 13/12/2021 à 20:46, Steven Rostedt a écrit :

quoted

On Mon, 13 Dec 2021 19:33:47 +0000
Christophe Leroy [off-list ref] wrote:

quoted

STill the same Oops, below

Unfortunately, I don't have a PPC machine (32 nor 64 bit) to help debug
this.

quoted

I will look more closely tomorrow.

OK, thanks.

The Oops was due to ftrace_caller() setting the regs argument to NULL.

After fixing that, I'm back into a situation where I get "Testing tracer 
function_graph: FAILED!"

Will continue investigating.

trace_selftest_startup_function_graph() calls register_ftrace_direct() 
which returns -ENOSUPP because powerpc doesn't select 
CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS.

Should TEST_DIRECT_TRAMP depend on CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS ?

Christophe