On Thu, Jul 09, 2026 at 01:40:06PM +0200, Christophe Leroy (CS GROUP) wrote:

Erhard reports failure of bitmap tests on powerpc:

  test_bitmap: loaded.
  test_bitmap: [lib/test_bitmap.c:397] bitmaps contents differ: expected "1,3-4,9", got "1,3-4,9,65-71,73-79,81-87,89-95,97-99"
  test_bitmap: parselist('0-2047:128/256'):    912
  test_bitmap: scnprintf("%*pbl", '0-32767'):    5977
  test_bitmap: test_bitmap_read_perf:        1191082
  test_bitmap: test_bitmap_write_perf:        1270153
  test_bitmap: failed 1 out of 208655 tests

The happens mainly when CONFIG_INIT_STACK_ALL_PATTERN is set.

Commit 6b5a4b687367 ("bitmap: Add test for out-of-boundary
modifications for scatter & gather") extended the test to
out-of-boundary bits, but those bits where left uninitialised.

Properly initialise the entire result bitmap before the test.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Thanks!

-- 
With Best Regards,
Andy Shevchenko