[PATCH] drm/xe/tests: avoid build warning on 32-bit targets

[PATCH] drm/xe/tests: avoid build warning on 32-bit targets

[Arnd Bergmann]

From: Arnd Bergmann <arnd@arndb.de>

Building the test case on 32-bit targets produces an integer overflow warning,
as a constant value is assigned to a 32-bit resource_size_t variable:

In file included from drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c:3329:
drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c: In function 'pf_gt_config_test_init':
drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c:14:25: error: conversion from 'long long unsigned int' to 'resource_size_t' {aka 'unsigned int'} changes value from '14940110848' to '2055208960' [-Werror=overflow]
   14 | #define TEST_VRAM       0x37a800000ull
      |                         ^~~~~~~~~~~~~~
drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c:71:29: note: in expansion of macro 'TEST_VRAM'
   71 |         vram->usable_size = TEST_VRAM;
      |                             ^~~~~~~~~

Shut up the warning with an extra cast that marks this truncation as intentional.
This is probably not the right fix here, but I could not figure out where the
constant value actually comes from, or if a smaller number would be appropriate
on a 32-bit system. It's possible that the test case or the driver is just not
useful on 32-bit machines because of other parts of the logic here.

Fixes: cbe29da6f7c0 ("drm/xe/tests: Add KUnit tests for new VRAM fair provisioning")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
If there is a better way to fix this, please treat this as a bug report and
just add a Reported-by tag in the commit.
---
 drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c b/drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c
index 305dbd4e5d1a..86cd15834bac 100644
--- a/drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c
+++ b/drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c
@@ -11,7 +11,7 @@
 #include "xe_pci_test.h"
 
 #define TEST_MAX_VFS	63
-#define TEST_VRAM	0x37a800000ull
+#define TEST_VRAM	(resource_size_t)0x37a800000ull
 
 static void pf_set_admin_mode(struct xe_device *xe, bool enable)
 {
-- 
2.39.5

Re: [PATCH] drm/xe/tests: avoid build warning on 32-bit targets

[Michal Wajdeczko]

Hi Arnd,


On 3/4/2026 9:37 AM, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> Building the test case on 32-bit targets produces an integer overflow warning,
> as a constant value is assigned to a 32-bit resource_size_t variable:
> 
> In file included from drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c:3329:
> drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c: In function 'pf_gt_config_test_init':
> drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c:14:25: error: conversion from 'long long unsigned int' to 'resource_size_t' {aka 'unsigned int'} changes value from '14940110848' to '2055208960' [-Werror=overflow]
>    14 | #define TEST_VRAM       0x37a800000ull
>       |                         ^~~~~~~~~~~~~~
> drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c:71:29: note: in expansion of macro 'TEST_VRAM'
>    71 |         vram->usable_size = TEST_VRAM;
>       |                             ^~~~~~~~~
> 
> Shut up the warning with an extra cast that marks this truncation as intentional.
> This is probably not the right fix here, but I could not figure out where the
> constant value actually comes from, or if a smaller number would be appropriate
> on a 32-bit system. It's possible that the test case or the driver is just not
> useful on 32-bit machines because of other parts of the logic here.
> 
> Fixes: cbe29da6f7c0 ("drm/xe/tests: Add KUnit tests for new VRAM fair provisioning")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> If there is a better way to fix this, please treat this as a bug report and
> just add a Reported-by tag in the commit.

this was already fixed and pushed [1]

[1] https://gitlab.freedesktop.org/drm/xe/kernel/-/commit/4f18a79b3585a28c9f73f859fe83f12d0eccc736

> ---
>  drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c b/drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c
> index 305dbd4e5d1a..86cd15834bac 100644
> --- a/drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c
> +++ b/drivers/gpu/drm/xe/tests/xe_gt_sriov_pf_config_kunit.c
> @@ -11,7 +11,7 @@
>  #include "xe_pci_test.h"
>  
>  #define TEST_MAX_VFS	63
> -#define TEST_VRAM	0x37a800000ull
> +#define TEST_VRAM	(resource_size_t)0x37a800000ull
>  
>  static void pf_set_admin_mode(struct xe_device *xe, bool enable)
>  {

Re: [PATCH] drm/xe/tests: avoid build warning on 32-bit targets

[Arnd Bergmann]

On Wed, Mar 4, 2026, at 09:51, Michal Wajdeczko wrote:
> On 3/4/2026 9:37 AM, Arnd Bergmann wrote:
>> From: Arnd Bergmann <arnd@arndb.de>
>> ---
>> If there is a better way to fix this, please treat this as a bug report and
>> just add a Reported-by tag in the commit.
>
> this was already fixed and pushed [1]
>
> [1] 
> https://gitlab.freedesktop.org/drm/xe/kernel/-/commit/4f18a79b3585a28c9f73f859fe83f12d0eccc736
>

Right, that looks better than my version. Apparently it just
missed the current linux-next that I was testing on.

     Arnd

Re: [PATCH] drm/xe/tests: avoid build warning on 32-bit targets

[Simon Richter]

Hi,

On 3/4/26 5:37 PM, Arnd Bergmann wrote:

> Shut up the warning with an extra cast that marks this truncation as intentional.
> This is probably not the right fix here, but I could not figure out where the
> constant value actually comes from, or if a smaller number would be appropriate
> on a 32-bit system. It's possible that the test case or the driver is just not
> useful on 32-bit machines because of other parts of the logic here.

vram->usable_size should be the same thing that gets reported during boot:

[    6.538254] xe 0030:03:00.0: [drm] VRAM[0]: Actual physical size 
0x0000000300000000, usable size exclude stolen 0x00000002fb800000, CPU 
accessible size 0x00000002fb800000

I think this should always be 64 bit wide, even on 32 bit architectures, 
because the VRAM exists and can be distributed to VFs, even if it cannot 
be accessed from the CPU.

    Simon