linux-kernel - Re: [PATCH v2 08/11] drm/xe: Remove driver side BAR release before resize

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: <87ecq0pxos.fsf@draig.linaro.org>
Date: Fri, 14 Nov 2025 13:10:11 +0000
From: Alex Bennée <alex.bennee@...aro.org>
To: Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com>
Cc: Simon Richter <Simon.Richter@...yros.de>,  Lucas De Marchi
 <lucas.demarchi@...el.com>,  Alex Deucher <alexander.deucher@....com>,
  amd-gfx@...ts.freedesktop.org,  Bjorn Helgaas <bhelgaas@...gle.com>,
  David Airlie <airlied@...il.com>,  dri-devel@...ts.freedesktop.org,
  intel-gfx@...ts.freedesktop.org,  intel-xe@...ts.freedesktop.org,  Jani
 Nikula <jani.nikula@...ux.intel.com>,  Joonas Lahtinen
 <joonas.lahtinen@...ux.intel.com>,  linux-pci@...r.kernel.org,  Rodrigo
 Vivi <rodrigo.vivi@...el.com>,  Simona Vetter <simona@...ll.ch>,  Tvrtko
 Ursulin <tursulin@...ulin.net>,  Christian König
 <christian.koenig@....com>,  Thomas Hellström
 <thomas.hellstrom@...ux.intel.com>,  Michał Winiarski
 <michal.winiarski@...el.com>,  linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 08/11] drm/xe: Remove driver side BAR release before
 resize

Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com> writes:

> PCI core handles releasing device's resources and their rollback in
> case of failure of a BAR resizing operation. Releasing resource prior
> to calling pci_resize_resource() prevents PCI core from restoring the
> BARs as they were.
>
> Remove driver-side release of BARs from the xe driver.
>
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com>
> Cc: Lucas De Marchi <lucas.demarchi@...el.com>
> ---
>  drivers/gpu/drm/xe/xe_vram.c | 3 ---
>  1 file changed, 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/xe_vram.c b/drivers/gpu/drm/xe/xe_vram.c
> index 00dd027057df..5aacab9358a4 100644
> --- a/drivers/gpu/drm/xe/xe_vram.c
> +++ b/drivers/gpu/drm/xe/xe_vram.c
> @@ -33,9 +33,6 @@ _resize_bar(struct xe_device *xe, int resno, resource_size_t size)
>  	int bar_size = pci_rebar_bytes_to_size(size);
>  	int ret;
>  
> -	if (pci_resource_len(pdev, resno))
> -		pci_release_resource(pdev, resno);
> -
>  	ret = pci_resize_resource(pdev, resno, bar_size, 0);
>  	if (ret) {
>  		drm_info(&xe->drm, "Failed to resize BAR%d to %dM (%pe). Consider enabling 'Resizable BAR' support in your BIOS\n",

This didn't apply, I assume due to a clash with:

  d30203739be79 (drm/xe: Move rebar to be done earlier)

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro