From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2A2BECDB47E for ; Wed, 18 Oct 2023 16:39:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A84898D0168; Wed, 18 Oct 2023 12:39:09 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A35218D0016; Wed, 18 Oct 2023 12:39:09 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 924E78D0168; Wed, 18 Oct 2023 12:39:09 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 837618D0016 for ; Wed, 18 Oct 2023 12:39:09 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 30D0040D7B for ; 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charset=us-ascii Content-Disposition: inline In-Reply-To: <20231018102952.3339837-8-liushixin2@huawei.com> X-Stat-Signature: yxfigswcrbf66159nuofrnw4ocgw9qau X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 63F651C002C X-Rspam-User: X-HE-Tag: 1697647147-79140 X-HE-Meta: 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 s8aE2g4E h50JCL3fRnvpxQCCxAtcr+ia0VaB0tgKLwQdLircWZuqGyAIvk65DwtsgoPmT3ok04CUY6CItXCNioT3WxG98557iN268h3mSp4rQvKXyzGC3M/J44kUEFXLwMCNC6Sh9vWPL7+ouZaFqDYUkiIQ49rzFCIvoimoQGR5oI749nYiKFJO09xFGS2RPcoiV4kbnp54n/07+FFXkeKh6+nWMphhtizfHuikBe+IAeTBNlmD9nmiMAD0FHkKlYgTZEZ9VktnDYfBAs9yoT+kvNnES7S7Dcqt8JsoYptfhQBiL/+VgFaYhw7B7y4Hv4Onl2o/4TTXLaX5MnoaSzPhG9ZYJUQa72WUazTpNhT4yBe/Tnl+z9LIQhaKsa10q2By63uclD1zBsaM3g9oZ8vUUG2/76KuAEK0q+Z899+tf9KxkQkDvtZxq4MKzL7mP19lHSYD+pZ5R 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: On Wed, Oct 18, 2023 at 06:29:52PM +0800, Liu Shixin wrote: > diff --git a/mm/kmemleak.c b/mm/kmemleak.c > index 7c9125c18956..a956b2734324 100644 > --- a/mm/kmemleak.c > +++ b/mm/kmemleak.c > @@ -816,16 +816,25 @@ static void delete_object_full(unsigned long ptr) > */ > static void delete_object_part(unsigned long ptr, size_t size, bool is_phys) > { > - struct kmemleak_object *object; > - unsigned long start, end; > + struct kmemleak_object *object, *object_l, *object_r; > + unsigned long start, end, flags; > + > + object_l = __alloc_object(GFP_KERNEL); > + if (!object_l) > + return; > > - object = find_and_remove_object(ptr, 1, is_phys); > + object_r = __alloc_object(GFP_KERNEL); > + if (!object_r) > + goto out; > + > + raw_spin_lock_irqsave(&kmemleak_lock, flags); > + object = __find_and_remove_object(ptr, 1, is_phys); > if (!object) { > #ifdef DEBUG > kmemleak_warn("Partially freeing unknown object at 0x%08lx (size %zu)\n", > ptr, size); > #endif > - return; > + goto unlock; > } > > /* > @@ -835,14 +844,25 @@ static void delete_object_part(unsigned long ptr, size_t size, bool is_phys) > */ > start = object->pointer; > end = object->pointer + object->size; > - if (ptr > start) > - __create_object(start, ptr - start, object->min_count, > - GFP_KERNEL, is_phys); > - if (ptr + size < end) > - __create_object(ptr + size, end - ptr - size, object->min_count, > - GFP_KERNEL, is_phys); > + if ((ptr > start) && > + !__link_object(object_l, start, ptr - start, > + object->min_count, is_phys)) > + object_l = NULL; > + if ((ptr + size < end) && > + !__link_object(object_r, ptr + size, end - ptr - size, > + object->min_count, is_phys)) > + object_r = NULL; > + > +unlock: > + raw_spin_unlock_irqrestore(&kmemleak_lock, flags); > + if (object) > + __delete_object(object); > > - __delete_object(object); > +out: > + if (object_l) > + mem_pool_free(object_l); > + if (object_r) > + mem_pool_free(object_r); > } Ah, I see now why __link_object() needs to do further object initialisation under the lock as prior to find_and_remove_object() we don't have all the information needed for object_l and object_r. Maybe in the __create_object splitting patch you can leave __alloc_object() just do the actual allocation and __link_object() do the full initialisation. Up to you, you can send a separate patch on top as I can see Andrew picked them up already. Otherwise the series looks fine. Reviewed-by: Catalin Marinas