Re: [PATCH v2] mm/damon/dbgfs: avoid duplicate context directory creation

On 8/20/22 00:19, SeongJae Park wrote:

From: Badari Pulavarty badari.pulavarty@intel.com

When user tries to create a DAMON context via the DAMON debugfs interface with a name of an already existing context, the context directory creation silently fails but the context is added in the internal data structure. As a result, memory could leak and DAMON cannot be turned on. An example test case is as below:

# cd /sys/kernel/debug/damon/
# echo "off" >  monitor_on
# echo paddr > target_ids
# echo "abc" > mk_context
# echo "abc" > mk_context
# echo $$ > abc/target_ids
# echo "on" > monitor_on  <<< fails

This commit fixes the issue by checking if the name already exist and immediately returning '-EEXIST' in the case.

Meh...

SJ, I have seen most (if not all of) your patches uses descriptive mood instead of imperative. Better say "Fix the issue by checking ...".