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From: Chengming Zhou In-Reply-To: <2ff52c5e-4b6b-4b3d-9047-f00967315d3e@suse.cz> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: 6875F140020 X-Stat-Signature: qbewwxg56bkrf8f1b4psn4dygxob6157 X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1717401974-845358 X-HE-Meta: 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 4PAW93xl a8O9lhgefHZ3nLkjANHETAokHaVJCQ86ZR0qZstO62eRi8J0HhNwv9MVXDTwMRxhqGTKyScjJbgl1rM6Zk2gqGMAZXd1ooq28SXGlkajK8YjIqm8uh/Nz9bR8lexgXNW1+c0sfU6BhQ8vG7308qtJdS5wVlOBJMgU1fTmyZnP0KPHlVwRYN189HDcHFSncBBa7gyu0HT9iXEUHvcXvQissLmR+PLbX3Mi2vnf X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2024/6/3 15:46, Vlastimil Babka wrote: > On 5/31/24 10:31 AM, Chengming Zhou wrote: >> On 2024/5/30 23:20, Christoph Lameter (Ampere) wrote: >>> On Tue, 28 May 2024, Chengming Zhou wrote: >>> >>>> diff --git a/mm/slub.c b/mm/slub.c >>>> index 0809760cf789..de57512734ac 100644 >>>> --- a/mm/slub.c >>>> +++ b/mm/slub.c >>>> @@ -1324,9 +1324,10 @@ static int check_object(struct kmem_cache *s, struct slab *slab, >>>>         } >>>>     } else { >>>>         if ((s->flags & SLAB_POISON) && s->object_size < s->inuse) { >>>> -            check_bytes_and_report(s, slab, p, "Alignment padding", >>>> +            if (!check_bytes_and_report(s, slab, p, "Alignment padding", >>>>                 endobject, POISON_INUSE, >>>> -                s->inuse - s->object_size); >>>> +                s->inuse - s->object_size)) >>>> +                return 0; >>>>         } >>>>     } >>> >>> This change means we will then skip the rest of the checks in check_object() such as the poison check. >> >> Yeah, only when this padding checking failed. >> >> Now, we always abort checking and return 0 when the first checking error happens, >> such as redzones checking above. > > Yes your patch will make it consistent. But IMHO it would be better to do > all the checks without skipping, report their specific error findings in > check_bytes_and_report() but not print_trailer(). Once all checks were done, > if any found an error, print the trailer once from check_object(). Thoughts? Ok, it's feasible, will change to this. > >> Thanks. >