Re: [RFC PATCH] mm/slab: fix a memory leak on kobject_init_and_add() failure

[Vlastimil Babka <vbabka@suse.cz>]

On 10/23/24 11:23, Hyeonggon Yoo wrote:
> On Wed, Oct 23, 2024 at 1:08 AM Christoph Lameter (Ampere)
> <cl@gentwo.org> wrote:
>>
>> On Tue, 22 Oct 2024, Vlastimil Babka wrote:
>>
>> > On 10/21/24 18:27, Christoph Lameter (Ampere) wrote:
>> > > On Mon, 21 Oct 2024, Vlastimil Babka wrote:
>> > >
>> > >> I think the comment "If this function returns an error, kobject_put() must
>> > >> be called" means that *if* you want to destroy it due to the failure, you
>> > >> must use kobject_put() and not e.g. kfree(). But IMHO it doesn't mean you
>> > >> must destroy it because of the kobject_add() failure.
>> > >
>> > > Right. The simplest solution is to see the sysfs stuff as optional. If it
>> >
>> > To clarify, I only meant the case of boot caches processed for sysfs later.
>> > I don't think we need to start ignoring all sysfs errors.
>>
>> Well not ignoring. Write something to the syslog. So it wont affect slab
>> operations. /sys support is not critical to the slab subsystem operations
>> and is often not used at all.
>>
>> If its conks out then it should be fixed but it should not impact current
>> operations. We have had so many issues with sysfs support in the past that
>> doing so would be wise to avoid future problems.
> 
> Both directions look fine to me. Christoph's approach would probably be better
> for maintainability I think? Failing to create sysfs files is not a
> critical problem anyway.

Yeah I guess, if it makes things simpler... Feel free to do that as v2 then!