Eric Lee / linux-smarc-t335x-v3.2

Download as
Browse Code ยป

Commit 3fa7c794fe4dc127f7fac3fad4d13628e68f89ce

Authored by Andi Kleen
Committed by Andi Kleen
1 parent 5a1b3999d6
Exists in master and in 4 other branches v3.2_AM335xPSP_04.06.00.11, v3.2_NEWT335xPSP_04.06.00.11, v3.2_SBC_SMARTMEN, v3.2_SMARCT335xPSP_04.06.00.11

[PATCH] Avoid recursion in lockdep when stack tracer takes locks 

The new dwarf2 unwinder needs to take locks to do backtraces
inside modules. This patch makes sure lockdep which calls
stacktrace is not reentered.

Thanks to Ingo for suggesting this simpler approach.

Cc: mingo@elte.hu
Signed-off-by: Andi Kleen <ak@suse.de>

Showing 1 changed file with 4 additions and 0 deletions Side-by-side Diff

... ... @@ -227,7 +227,11 @@
227 227 trace->skip = 3;
228 228 trace->all_contexts = 0;
229 229  
  230 + /* Make sure to not recurse in case the the unwinder needs to tak
  231 +e locks. */
  232 + lockdep_off();
230 233 save_stack_trace(trace, NULL);
  234 + lockdep_on();
231 235  
232 236 trace->max_entries = trace->nr_entries;
233 237