From: Jinliang Zheng alexjlzheng@tencent.com
In the dirty_ratio_handler() function, vm_dirty_bytes must be set to zero before calling writeback_set_ratelimit(), as global_dirty_limits() always prioritizes the value of vm_dirty_bytes.
That causes ratelimit_pages to still use the value calculated based on vm_dirty_bytes, which is wrong now.
Fixes: 9d823e8f6b1b ("writeback: per task dirty rate limit") Signed-off-by: Jinliang Zheng alexjlzheng@tencent.com Reviewed-by: MengEn Sun mengensun@tencent.com Cc: stable@vger.kernel.org --- Changelog: v2: A more detailed description v1: https://lore.kernel.org/linux-fsdevel/20250415083542.6946-1-alexjlzheng@tenc... --- mm/page-writeback.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/page-writeback.c b/mm/page-writeback.c index c81624bc3969..20e1d76f1eba 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -520,8 +520,8 @@ static int dirty_ratio_handler(const struct ctl_table *table, int write, void *b
ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); if (ret == 0 && write && vm_dirty_ratio != old_ratio) { - writeback_set_ratelimit(); vm_dirty_bytes = 0; + writeback_set_ratelimit(); } return ret; }