2018-02-22 11:50:08

by Arnd Bergmann

Subject: [PATCH] drm: fix drm_get_max_iomem type mismatch

When comparing two variables with min()/max(), they should be the same type:

drivers/gpu/drm/drm_memory.c: In function 'drm_get_max_iomem':
include/linux/kernel.h:821:16: error: comparison of distinct pointer types lacks a cast [-Werror]
(void) (&max1 == &max2);

This makes the local variable in drm_get_max_iomem make the type
from resource->end.

Fixes: 82626363a217 ("drm: add func to get max iomem address v2")
Signed-off-by: Arnd Bergmann <[email protected]>
---
drivers/gpu/drm/drm_memory.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_memory.c b/drivers/gpu/drm/drm_memory.c
index 7ca500b8c399..3c54044214db 100644
--- a/drivers/gpu/drm/drm_memory.c
+++ b/drivers/gpu/drm/drm_memory.c
@@ -153,7 +153,7 @@ EXPORT_SYMBOL(drm_legacy_ioremapfree);
u64 drm_get_max_iomem(void)
{
struct resource *tmp;
- u64 max_iomem = 0;
+ resource_size_t max_iomem = 0;

for (tmp = iomem_resource.child; tmp; tmp = tmp->sibling) {
max_iomem = max(max_iomem, tmp->end);
--
2.9.0

2018-02-22 16:25:46

by Sean Paul

Subject: Re: [PATCH] drm: fix drm_get_max_iomem type mismatch

On Thu, Feb 22, 2018 at 12:47:51PM +0100, Arnd Bergmann wrote:
> When comparing two variables with min()/max(), they should be the same type:
>
> drivers/gpu/drm/drm_memory.c: In function 'drm_get_max_iomem':
> include/linux/kernel.h:821:16: error: comparison of distinct pointer types lacks a cast [-Werror]
> (void) (&max1 == &max2);
>
> This makes the local variable in drm_get_max_iomem make the type
> from resource->end.
>
> Fixes: 82626363a217 ("drm: add func to get max iomem address v2")
> Signed-off-by: Arnd Bergmann <[email protected]>

Thanks Arnd, I've applied this to drm-misc-next.

Sean

> ---
> drivers/gpu/drm/drm_memory.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/drm_memory.c b/drivers/gpu/drm/drm_memory.c
> index 7ca500b8c399..3c54044214db 100644
> --- a/drivers/gpu/drm/drm_memory.c
> +++ b/drivers/gpu/drm/drm_memory.c
> @@ -153,7 +153,7 @@ EXPORT_SYMBOL(drm_legacy_ioremapfree);
> u64 drm_get_max_iomem(void)
> {
> struct resource *tmp;
> - u64 max_iomem = 0;
> + resource_size_t max_iomem = 0;
>
> for (tmp = iomem_resource.child; tmp; tmp = tmp->sibling) {
> max_iomem = max(max_iomem, tmp->end);
> --
> 2.9.0
>

--
Sean Paul, Software Engineer, Google / Chromium OS