On Tue, 02 Jun 2026, "Saarinen, Jani" <[email protected]> wrote:
> Hi,
>> -----Original Message-----
>> From: Thomas Zimmermann <[email protected]>
>> Sent: Tuesday, 2 June 2026 10.30
>> To: [email protected]; [email protected]; Saarinen,
>> Jani <[email protected]>; [email protected]; [email protected];
>> [email protected]; [email protected]
>> Cc: [email protected]; [email protected]; intel-
>> [email protected]; Thomas Zimmermann <[email protected]>
>> Subject: [PATCH] drm/dumb-buffers: Increase size limits to match current
>> devices
>>
>> Increase the limits for dumb-buffer arguments to sizes of 16384x16384 at 64
>> bpp. Such buffer sizes are still within 32-bit unsigned limits.
>> Fixes CI and high-end devices.
>>
>> Signed-off-by: Thomas Zimmermann <[email protected]>
>> Fixes: 5ab62dd3687b ("drm: prevent integer overflows in dumb buffer
>> creation helpers")
>> Reported-by: Jani Nikula <[email protected]>
>> Closes: https://lore.kernel.org/dri-
>> devel/[email protected]/
>
> Seems not helping on i915 CI BAT issue
> https://lore.kernel.org/intel-gfx/178038951063.34290.3796875109342598028@6beec6c84f66/T/#u
>
> => https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_167719v1/index.html?
Right, so vgem_basic has this, among other things:
bo.width = 1<<15;
bo.height = 1<<15;
bo.bpp = 16;
vgem_create(fd, &bo);
i.e. 32768x32768.
Not so sure about this one.
Anyone else care to chime in?
BR,
Jani.
>
>> Cc: Rajat Gupta <[email protected]>
>> Cc: Thomas Zimmermann <[email protected]>
>> Cc: Maarten Lankhorst <[email protected]>
>> Cc: Maxime Ripard <[email protected]>
>
> Br,
> Jani
>
>> ---
>> drivers/gpu/drm/drm_dumb_buffers.c | 9 +++++----
>> 1 file changed, 5 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/drm_dumb_buffers.c
>> b/drivers/gpu/drm/drm_dumb_buffers.c
>> index e60130b2bb0c..9c4cfb3210aa 100644
>> --- a/drivers/gpu/drm/drm_dumb_buffers.c
>> +++ b/drivers/gpu/drm/drm_dumb_buffers.c
>> @@ -201,11 +201,12 @@ int drm_mode_create_dumb(struct drm_device
>> *dev,
>> if (!args->width || !args->height || !args->bpp)
>> return -EINVAL;
>>
>> - /* Reject unreasonable inputs early. Dumb buffers are for software
>> - * rendering; nothing legitimate needs more than 8192x8192 at
>> 32bpp.
>> - * This prevents overflows in downstream alignment helpers.
>> + /*
>> + * Reject unreasonable inputs early. Dumb buffers are for software
>> + * rendering; nothing legitimate needs more than 16384x16384 at
>> + * 64 bpp. This prevents overflows in downstream alignment helpers.
>> */
>> - if (args->width >= 8192 || args->height >= 8192 || args->bpp > 32)
>> + if (args->width > 16384 || args->height > 16384 || args->bpp > 64)
>> return -EINVAL;
>>
>> /* overflow checks for 32bit size calculations */
>>
>> base-commit: a980196655477a8f5067112946401fe52e510664
>> --
>> 2.54.0
>
--
Jani Nikula, Intel
