Re: [PATCH 2/2] selftests/mm: restore hidden hugetlb reservation scenarios

[Andrew Morton]

On Tue, 14 Jul 2026 10:16:30 +0800 Song Hu <husong@xxxxxxxxxx> wrote:

> A stray 'continue' in the main loop of charge_reserved_hugetlb.sh made
> the "more than reservation", "more than cgroup limit", and "multiple
> cgroups" scenarios unreachable, so they never ran.
> 
> Remove it so the first two run again.

OK.

> The third,
> run_multiple_cgroup_test(), is separately broken -- a backslash
> line-continuation breaks its local declarations and its hugetlb
> reservation accounting does not charge as expected -- and has never run
> in CI; skip it explicitly with a comment until fixed.

That's reasonable.  This code was added by Mina six years ago.  But
he's still around so let's bug him with a cc ;)

> Also correct two
> `[[ "$method" == 2"" ]]` typos (harmless empty-string concatenation)
> to plain `2`.

OK.



From: Song Hu <husong@xxxxxxxxxx>
Subject: selftests/mm: restore hidden hugetlb reservation scenarios
Date: Tue, 14 Jul 2026 10:16:30 +0800

A stray 'continue' in the main loop of charge_reserved_hugetlb.sh made the
"more than reservation", "more than cgroup limit", and "multiple cgroups"
scenarios unreachable, so they never ran.

Remove it so the first two run again.  The third,
run_multiple_cgroup_test(), is separately broken -- a backslash
line-continuation breaks its local declarations and its hugetlb
reservation accounting does not charge as expected -- and has never run in
CI; skip it explicitly with a comment until fixed.  Also correct two `[[
"$method" == 2"" ]]` typos (harmless empty-string concatenation) to plain
`2`.

Link: https://lore.kernel.org/20260714021630.1063823-1-husong@xxxxxxxxxx
Signed-off-by: Song Hu <husong@xxxxxxxxxx>
Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Liam R. Howlett <liam@xxxxxxxxxxxxx>
Cc: Lorenzo Stoakes <ljs@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxx>
Cc: Muchun Song <muchun.song@xxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxxxxx>
Cc: Mina Almasry <almasrymina@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 tools/testing/selftests/mm/charge_reserved_hugetlb.sh |   14 +++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

--- a/tools/testing/selftests/mm/charge_reserved_hugetlb.sh~selftests-mm-restore-hidden-hugetlb-reservation-scenarios
+++ a/tools/testing/selftests/mm/charge_reserved_hugetlb.sh
@@ -439,11 +439,11 @@ for populate in "" "-o"; do
         fi
 
         # Skip populated shmem tests. Doesn't seem to be supported.
-        if [[ "$method" == 2"" ]] && [[ "$populate" == "-o" ]]; then
+        if [[ "$method" == 2 ]] && [[ "$populate" == "-o" ]]; then
           continue
         fi
 
-        if [[ "$method" == 2"" ]] && [[ "$reserve" == "-n" ]]; then
+        if [[ "$method" == 2 ]] && [[ "$reserve" == "-n" ]]; then
           continue
         fi
 
@@ -496,7 +496,6 @@ for populate in "" "-o"; do
         echo 'PASS'
 
         cleanup
-        continue
         echo
         echo
         echo
@@ -530,6 +529,15 @@ for populate in "" "-o"; do
 
         cleanup
 
+        # The "multiple cgroups" scenario (run_multiple_cgroup_test) is
+        # multiply broken and has never run in CI: a backslash
+        # line-continuation breaks its local declarations, it passes
+        # reservation sizes in bytes rather than pages (unlike
+        # run_test), and its assertions compare page counts to byte
+        # values. Skip it until properly rewritten; the two scenarios
+        # above are restored by this change.
+        continue
+
         echo
         echo
         echo
_