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Mon, 01 Jun 2026 08:31:55 -0400 X-MC-Unique: mRYfuuFhM2i8ajN0B6e56Q-1 X-Mimecast-MFC-AGG-ID: mRYfuuFhM2i8ajN0B6e56Q_1780317114 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id CC7D51956060; Mon, 1 Jun 2026 12:31:53 +0000 (UTC) Received: from fedora (unknown [10.44.48.10]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id A342B1800577; Mon, 1 Jun 2026 12:31:50 +0000 (UTC) Received: by fedora (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Mon, 1 Jun 2026 14:31:53 +0200 (CEST) Date: Mon, 1 Jun 2026 14:31:49 +0200 From: Oleg Nesterov To: "David Hildenbrand (Arm)" Cc: Andrew Morton , Christian Brauner , Jann Horn , Kees Cook , Lorenzo Stoakes , Michal Hocko , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v2] mm_access: simplify the security checks Message-ID: References: MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 X-Mimecast-MFC-PROC-ID: xjtQhgAW2GIJIT7s-KKFIJaTZNzMFxitXUjWunfZedk_1780317114 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: CC3F3C0012 X-Stat-Signature: u3euogk9wmn57wzkw9f1i5wx88wonqos X-HE-Tag: 1780317121-685734 X-HE-Meta: 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 5HSZN1pj YlMpj39JLSxvEux5ruvWvXGO678yPA2j5YtmU6EwZE0Jf227UZVBZveqNvF82Dvc8K2YvTkPma89EIjbF8ektp0K9n5ve8SjX+w2+v8tiE9yuowNjtZNT7iTtzKIy5CK9HEkSWWit5J+sbr2CyOeslVb7aIsu72mcAOvUkFbDUd1NUVVWGd++movcBqBNM2TVGCn0bzgVIahMBIkJPLcZ/gRssqjCBVd2VOCHW47rE9hPelVJuvxRce1Y7bMtVeQkk7kmmoJVE4LJGe9MN9/Veu7vOWY5rszfGHywPuZ9qFmj1MVWvQJM3XstOcqoccalhVqn3B998EzgA0kx32g3jkM6KYiOtTGV11J/pL3F/s/z/l83gXOO99O+GrgMMD+nKll+SxlZK3nsUEU= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 06/01, David Hildenbrand (Arm) wrote: > > On 5/30/26 16:12, Oleg Nesterov wrote: > > I am not sure I spot the "simplification" here? Ah, then lets forget this patch ;) Cleanups are always subjective, if maintainer doesn't agree - forget it. > Looks more like an optimization that makes the code slightly more complicated. I don't think that !task->mm or current->mm == task->mm is the common case. Just the code looks more clear to me if it takes exec_update_lock only when necessary. But see above, please forget. Oleg.