[PATCH] mm/smaps_rollup: return empty file for kthreads instead of ESRCH

From: Alex Xu (Hello71)
Date: Wed Apr 13 2022 - 17:16:37 EST


This restores the behavior prior to 258f669e7e88 ("mm:
/proc/pid/smaps_rollup: convert to single value seq_file"), making it
once again consistent with maps and smaps, and allowing patterns like
awk '$1=="Anonymous:"{x+=$2}END{print x}' /proc/*/smaps_rollup to work.
Searching all Debian packages for "smaps_rollup" did not find any
programs which would be affected by this change.

Fixes: 258f669e7e88 ("mm: /proc/pid/smaps_rollup: convert to single value seq_file")

Signed-off-by: Alex Xu (Hello71) <alex_y_xu@xxxxxxxx>
---
fs/proc/task_mmu.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index f46060eb91b5..d7de4584a271 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -883,10 +883,8 @@ static int show_smaps_rollup(struct seq_file *m, void *v)
return -ESRCH;

mm = priv->mm;
- if (!mm || !mmget_not_zero(mm)) {
- ret = -ESRCH;
+ if (!mm || !mmget_not_zero(mm))
goto out_put_task;
- }

memset(&mss, 0, sizeof(mss));

--
2.35.2