The quilt patch titled
Subject: selftests/mm: don't fail uffd-stress if too many CPUs
has been removed from the -mm tree. Its filename was
selftests-mm-dont-fail-uffd-stress-if-too-many-cpus.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Brendan Jackman <jackmanb@xxxxxxxxxx>
Subject: selftests/mm: don't fail uffd-stress if too many CPUs
Date: Tue, 11 Mar 2025 13:18:17 +0000
This calculation divides a fixed parameter by an environment-dependent
parameter i.e. the number of CPUs.
The simple way to avoid machine-specific failures here is to just put a
cap on the max value of the latter.
Link: https://lkml.kernel.org/r/20250311-mm-selftests-v4-6-dec210a658f5@xxxxxxxxxx
Signed-off-by: Brendan Jackman <jackmanb@xxxxxxxxxx>
Suggested-by: Mateusz Guzik <mjguzik@xxxxxxxxx>
Cc: Dev Jain <dev.jain@xxxxxxx>
Cc: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/mm/uffd-stress.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
--- a/tools/testing/selftests/mm/uffd-stress.c~selftests-mm-dont-fail-uffd-stress-if-too-many-cpus
+++ a/tools/testing/selftests/mm/uffd-stress.c
@@ -435,6 +435,7 @@ static void sigalrm(int sig)
int main(int argc, char **argv)
{
+ unsigned long nr_cpus;
size_t bytes;
if (argc < 4)
@@ -453,7 +454,15 @@ int main(int argc, char **argv)
return KSFT_SKIP;
}
- nr_parallel = sysconf(_SC_NPROCESSORS_ONLN);
+ nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+ if (nr_cpus > 32) {
+ /* Don't let calculation below go to zero. */
+ ksft_print_msg("_SC_NPROCESSORS_ONLN (%lu) too large, capping nr_threads to 32\n",
+ nr_cpus);
+ nr_parallel = 32;
+ } else {
+ nr_parallel = nr_cpus;
+ }
nr_pages_per_cpu = bytes / page_size / nr_parallel;
if (!nr_pages_per_cpu) {
_
Patches currently in -mm which might be from jackmanb@xxxxxxxxxx are
scripts-gdb-add-lx_per_cpu_ptr.patch
