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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 41C95CAC59A for ; Fri, 19 Sep 2025 07:39:01 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 93AE78E005E; Fri, 19 Sep 2025 03:39:00 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 912D58E0022; Fri, 19 Sep 2025 03:39:00 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 84F818E005E; Fri, 19 Sep 2025 03:39:00 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 77E8A8E0022 for ; Fri, 19 Sep 2025 03:39:00 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 24B6714059A for ; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 21961160009 X-Rspam-User: X-Rspamd-Server: rspam07 X-Stat-Signature: nhpid9tanhw69ozgcr6en3w4hafiaggq X-HE-Tag: 1758267537-757947 X-HE-Meta: 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 1wLdn1WD kCWoLdd1LWTERFTpjs9laX86hiBHi6cdao/YJxPaez2fWNv65fK+Xf1jOb8UHDxxz/XlCX6fTRgHfmq5JS0xqkrCHS2A1zLE6Gal9CRmGuVWywFJqZ1Oza+ORtg/b8OmUB4z56xt5JoPSOawGc2nQ1XppUVfv3qmAwJqGIZmLfU3ifo/VwuiQAC6J97kBOkFNa7ZsU3pIudwQfTo4C6WZxb5EdRVVEoHc+L7Cp02qQVSryHiH5Noe4e7IfWLljWYjq7+LMi2O+WxwXwuTkGNReDgwcjEwMlmirP0zQFiiAcz882/4ZTquxP2GoI/letyL75xplDv/i3/ExmIyFv6vHK5UnAgHYEJnD0M6boP5MdSj+Ty8RrSo2yKyOQ== 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 19/09/25 12:42 pm, Wei Yang wrote: > When using mm_slot in ksm, there is code snip like: > > slot = mm_slot_lookup(mm_slots_hash, mm); > mm_slot = mm_slot_entry(slot, struct ksm_mm_slot, slot); > if (mm_slot && ..) { > } > > The mm_slot_entry() won't return a valid value if slot is NULL > generally. But currently it works since slot is the first element of > struct ksm_mm_slot. > > To reduce the ambiguity and make it robust, access mm_slot_entry() when > slot is !NULL. > > Signed-off-by: Wei Yang Reviewed-by: Dev Jain