linux-kernel - Re: [PATCH 2/8] drm/gem: Introduce drm_gem_get_unmapped

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250930124554.5459194c@fedora>
Date: Tue, 30 Sep 2025 12:45:54 +0200
From: Boris Brezillon <boris.brezillon@...labora.com>
To: Loïc Molinari <loic.molinari@...labora.com>
Cc: Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>, Maxime Ripard
 <mripard@...nel.org>, Thomas Zimmermann <tzimmermann@...e.de>, David Airlie
 <airlied@...il.com>, Simona Vetter <simona@...ll.ch>, Jani Nikula
 <jani.nikula@...ux.intel.com>, Joonas Lahtinen
 <joonas.lahtinen@...ux.intel.com>, Rodrigo Vivi <rodrigo.vivi@...el.com>,
 Tvrtko Ursulin <tursulin@...ulin.net>, Rob Herring <robh@...nel.org>,
 Steven Price <steven.price@....com>, Liviu Dudau <liviu.dudau@....com>,
 Melissa Wen <mwen@...lia.com>, Maíra Canal
 <mcanal@...lia.com>, Hugh Dickins <hughd@...gle.com>, Baolin Wang
 <baolin.wang@...ux.alibaba.com>, Andrew Morton <akpm@...ux-foundation.org>,
 Al Viro <viro@...iv.linux.org.uk>, Mikołaj Wasiak
 <mikolaj.wasiak@...el.com>, Christian Brauner <brauner@...nel.org>, Nitin
 Gote <nitin.r.gote@...el.com>, Andi Shyti <andi.shyti@...ux.intel.com>,
 linux-kernel@...r.kernel.org, dri-devel@...ts.freedesktop.org,
 intel-gfx@...ts.freedesktop.org, linux-mm@...ck.org, kernel@...labora.com
Subject: Re: [PATCH 2/8] drm/gem: Introduce drm_gem_get_unmapped_area() fop

On Tue, 30 Sep 2025 12:30:03 +0200
Boris Brezillon <boris.brezillon@...labora.com> wrote:

> > +unsigned long drm_gem_get_unmapped_area(struct file *filp, unsigned long uaddr,
> > +					unsigned long len, unsigned long pgoff,
> > +					unsigned long flags)
> > +{
> > +#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > +	struct drm_gem_object *obj;
> > +	unsigned long ret;
> > +
> > +	obj = drm_gem_object_lookup_from_offset(filp, pgoff, len >> PAGE_SHIFT);
> > +	if (IS_ERR(obj))  
> 
> Is this supposed to happen? If not, I'd be tempted to add a
> WARN_ON_ONCE().

Taking that back. I think you need it for non-GEM backed mappings, like
userland IOMEM mappings.

> 
> > +		return mm_get_unmapped_area(current->mm, filp, uaddr, len, 0,
> > +					    flags);
> > +