From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout-p-103.mailbox.org (mout-p-103.mailbox.org [80.241.56.161]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A26E4351C13 for ; Tue, 3 Mar 2026 17:04:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.161 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772557472; cv=none; b=nb4OPmwoTjwCYUGqHKvGtsHTlrozbm1rbo+x0Ix+XSJprFxuxiOjT7QpQ9bRg4MMMcDYdllajUwCjfOwRip8hRI8y1jNLjZSibSNxDMKqSos3SftYGCS3lxIIRfL3mVpSyTluf0cgtJ+GbrCbGlKAwpRi2iSaLWyLXe+YYMi2ZU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772557472; c=relaxed/simple; bh=mcVQO/iOk0oaelPmFyCYQjWaHKgwNm9YIJAsCHqidzY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=rOkYx4+HdDBhi191UjRDKemDa8qpmYaJU26eFZhgtSlzqFutB3xwHYqIXW5InoOa0xF5+vR4/VRhFO0qbmo7BUz4O7Lo05eOaKWjdFEpn9iPEw6eriE0Dpz6mvXQJ5ao/sk+YnH7qGqX1CNzCwoAqVZLDh4LXGa8evyZfjots+A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org; spf=pass smtp.mailfrom=mailbox.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b=QEA4DOqm; arc=none smtp.client-ip=80.241.56.161 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mailbox.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b="QEA4DOqm" Received: from smtp202.mailbox.org (smtp202.mailbox.org [IPv6:2001:67c:2050:b231:465::202]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-103.mailbox.org (Postfix) with ESMTPS id 4fQMbY2dm5z9tCf; Tue, 3 Mar 2026 18:04:25 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mailbox.org; s=mail20150812; t=1772557465; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=kCRAe7/440BxraKG/cItAfoYxTETeJxPcvjRNNEGyWM=; b=QEA4DOqmWNlgcFQEBP2PDguIaTaYCyEQ4sgDcZqRRuyrq3zGJpHf3ENvYiKb3VzNja9O2V 9kD+bR58zzfNlxFy/Ah3fpPeaCnhhsTCiuJwq0nmzC7y+J+lIBGgYiQFYQxtqh5S/XZ5Wm eBL0/eG3JknBTbT3OpSJqgryCvs9z+2r8patOvJbbmiylULped4l5Me4Ttbpx/S3rQSX3Z ArgA6ob2ocOKxHJKHhXWORRfiLBBzLcDnHBwEWoo1UdkvyrnP/bP4xraQdrX1PAcPrea3R Knx5gTa4D+fKPn6Sp2nZFMe61bMTit9Xdxs2zBARg2IPNSddvJ1rzL5WekVKoQ== Message-ID: Date: Tue, 3 Mar 2026 18:04:21 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH] drm/syncobj: Fix handle <-> fd ioctls with dirty stack To: Julian Orth , Maarten Lankhorst Cc: =?UTF-8?Q?Christian_K=C3=B6nig?= , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Dmitry Osipenko , Rob Clark , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org References: <20260301-point-v1-1-21fc5fd98614@gmail.com> <3c969254-ed38-4b13-84b3-5afa365b04cb@amd.com> <2b75199f-b78a-4915-8e75-5d186f63f7c5@mailbox.org> From: =?UTF-8?Q?Michel_D=C3=A4nzer?= Content-Language: en-CA In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-MBO-RS-ID: 00174101e56b1735e45 X-MBO-RS-META: 5owebwwq5z3j4yw8mroiob3by1qz7szg On 3/3/26 17:54, Julian Orth wrote: > On Tue, Mar 3, 2026 at 5:40 PM Maarten Lankhorst > wrote: >> >> There is precedence in the ioctl, the pad member is checked against zero for the same reason. > > I don't believe that this is comparable. Developers of code developed > against an older kernel could look at the kernel and see that the pad > field was checked against zero. They could not see the same for fields > that didn't exist at the time. "Initialize only known fields" isn't a valid approach here. The full struct must be initialized to 0, including any fields added in the future. -- Earthling Michel Dänzer \ GNOME / Xwayland / Mesa developer https://redhat.com \ Libre software enthusiast