* [PATCH] drm/amdgpu: fix 32-bit compiler warning
@ 2015-10-07 7:41 Arnd Bergmann
2015-10-07 8:57 ` Christian König
0 siblings, 1 reply; 5+ messages in thread
From: Arnd Bergmann @ 2015-10-07 7:41 UTC (permalink / raw)
To: linux-arm-kernel
The new amdgpu driver passes a user space pointer in a 64-bit structure
member, which is the correct way to do it, but it attempts to
directly cast it to a __user pointer in the kernel, which causes
a warning in three places:
drm/amd/amdgpu/amdgpu_cs.c: In function 'amdgpu_cs_parser_init':
drm/amd/amdgpu/amdgpu_cs.c:180:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
chunk_array_user = (uint64_t __user *)(cs->in.chunks);
This changes all three to add an intermediate cast to 'unsigned long'
as other drivers do. This avoids the warning and works correctly on
both 32-bit and 64-bit architectures.
Signed-off-by: Arnd Bergmann <arnd@arndb•de>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index cb3c274edb0a..fd16652aa277 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -177,7 +177,7 @@ int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, void *data)
/* get chunks */
INIT_LIST_HEAD(&p->validated);
- chunk_array_user = (uint64_t __user *)(cs->in.chunks);
+ chunk_array_user = (uint64_t __user *)(unsigned long)(cs->in.chunks);
if (copy_from_user(chunk_array, chunk_array_user,
sizeof(uint64_t)*cs->in.num_chunks)) {
ret = -EFAULT;
@@ -197,7 +197,7 @@ int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, void *data)
struct drm_amdgpu_cs_chunk user_chunk;
uint32_t __user *cdata;
- chunk_ptr = (void __user *)chunk_array[i];
+ chunk_ptr = (void __user *)(unsigned long)chunk_array[i];
if (copy_from_user(&user_chunk, chunk_ptr,
sizeof(struct drm_amdgpu_cs_chunk))) {
ret = -EFAULT;
@@ -208,7 +208,7 @@ int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, void *data)
p->chunks[i].length_dw = user_chunk.length_dw;
size = p->chunks[i].length_dw;
- cdata = (void __user *)user_chunk.chunk_data;
+ cdata = (void __user *)(unsigned long)user_chunk.chunk_data;
p->chunks[i].user_ptr = cdata;
p->chunks[i].kdata = drm_malloc_ab(size, sizeof(uint32_t));
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH] drm/amdgpu: fix 32-bit compiler warning
2015-10-07 7:41 [PATCH] drm/amdgpu: fix 32-bit compiler warning Arnd Bergmann
@ 2015-10-07 8:57 ` Christian König
2015-10-07 9:18 ` Arnd Bergmann
2015-10-07 9:21 ` Chris Wilson
0 siblings, 2 replies; 5+ messages in thread
From: Christian König @ 2015-10-07 8:57 UTC (permalink / raw)
To: linux-arm-kernel
On 07.10.2015 09:41, Arnd Bergmann wrote:
> The new amdgpu driver passes a user space pointer in a 64-bit structure
> member, which is the correct way to do it, but it attempts to
> directly cast it to a __user pointer in the kernel, which causes
> a warning in three places:
>
> drm/amd/amdgpu/amdgpu_cs.c: In function 'amdgpu_cs_parser_init':
> drm/amd/amdgpu/amdgpu_cs.c:180:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
> chunk_array_user = (uint64_t __user *)(cs->in.chunks);
>
> This changes all three to add an intermediate cast to 'unsigned long'
> as other drivers do. This avoids the warning and works correctly on
> both 32-bit and 64-bit architectures.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb•de>
Well if I'm not completely mistaken this is the second time we need to
fix this because somebody thought the cast was unnecessary.
Anyway the patch is Reviewed-by: Christian K?nig
<christian.koenig@amd•com> and I'm going to keep an eye open for the
next time somebody tries to remove this.
Regards,
Christian.
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> index cb3c274edb0a..fd16652aa277 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> @@ -177,7 +177,7 @@ int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, void *data)
>
> /* get chunks */
> INIT_LIST_HEAD(&p->validated);
> - chunk_array_user = (uint64_t __user *)(cs->in.chunks);
> + chunk_array_user = (uint64_t __user *)(unsigned long)(cs->in.chunks);
> if (copy_from_user(chunk_array, chunk_array_user,
> sizeof(uint64_t)*cs->in.num_chunks)) {
> ret = -EFAULT;
> @@ -197,7 +197,7 @@ int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, void *data)
> struct drm_amdgpu_cs_chunk user_chunk;
> uint32_t __user *cdata;
>
> - chunk_ptr = (void __user *)chunk_array[i];
> + chunk_ptr = (void __user *)(unsigned long)chunk_array[i];
> if (copy_from_user(&user_chunk, chunk_ptr,
> sizeof(struct drm_amdgpu_cs_chunk))) {
> ret = -EFAULT;
> @@ -208,7 +208,7 @@ int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, void *data)
> p->chunks[i].length_dw = user_chunk.length_dw;
>
> size = p->chunks[i].length_dw;
> - cdata = (void __user *)user_chunk.chunk_data;
> + cdata = (void __user *)(unsigned long)user_chunk.chunk_data;
> p->chunks[i].user_ptr = cdata;
>
> p->chunks[i].kdata = drm_malloc_ab(size, sizeof(uint32_t));
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH] drm/amdgpu: fix 32-bit compiler warning
2015-10-07 8:57 ` Christian König
@ 2015-10-07 9:18 ` Arnd Bergmann
2015-10-07 14:00 ` Alex Deucher
2015-10-07 9:21 ` Chris Wilson
1 sibling, 1 reply; 5+ messages in thread
From: Arnd Bergmann @ 2015-10-07 9:18 UTC (permalink / raw)
To: linux-arm-kernel
On Wednesday 07 October 2015 10:57:11 Christian K?nig wrote:
> On 07.10.2015 09:41, Arnd Bergmann wrote:
> > The new amdgpu driver passes a user space pointer in a 64-bit structure
> > member, which is the correct way to do it, but it attempts to
> > directly cast it to a __user pointer in the kernel, which causes
> > a warning in three places:
> >
> > drm/amd/amdgpu/amdgpu_cs.c: In function 'amdgpu_cs_parser_init':
> > drm/amd/amdgpu/amdgpu_cs.c:180:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
> > chunk_array_user = (uint64_t __user *)(cs->in.chunks);
> >
> > This changes all three to add an intermediate cast to 'unsigned long'
> > as other drivers do. This avoids the warning and works correctly on
> > both 32-bit and 64-bit architectures.
> >
> > Signed-off-by: Arnd Bergmann <arnd@arndb•de>
>
> Well if I'm not completely mistaken this is the second time we need to
> fix this because somebody thought the cast was unnecessary.
>
> Anyway the patch is Reviewed-by: Christian K?nig
> <christian.koenig@amd•com> and I'm going to keep an eye open for the
> next time somebody tries to remove this.
>
Ok, thanks.
I guess I should have added
Fixes: e60b344f6c0eff ("drm/amdgpu: optimize amdgpu_parser_init")
Arnd
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH] drm/amdgpu: fix 32-bit compiler warning
2015-10-07 8:57 ` Christian König
2015-10-07 9:18 ` Arnd Bergmann
@ 2015-10-07 9:21 ` Chris Wilson
1 sibling, 0 replies; 5+ messages in thread
From: Chris Wilson @ 2015-10-07 9:21 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, Oct 07, 2015 at 10:57:11AM +0200, Christian K?nig wrote:
> On 07.10.2015 09:41, Arnd Bergmann wrote:
> >The new amdgpu driver passes a user space pointer in a 64-bit structure
> >member, which is the correct way to do it, but it attempts to
> >directly cast it to a __user pointer in the kernel, which causes
> >a warning in three places:
> >
> >drm/amd/amdgpu/amdgpu_cs.c: In function 'amdgpu_cs_parser_init':
> >drm/amd/amdgpu/amdgpu_cs.c:180:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
> > chunk_array_user = (uint64_t __user *)(cs->in.chunks);
> >
> >This changes all three to add an intermediate cast to 'unsigned long'
> >as other drivers do. This avoids the warning and works correctly on
> >both 32-bit and 64-bit architectures.
> >
> >Signed-off-by: Arnd Bergmann <arnd@arndb•de>
>
> Well if I'm not completely mistaken this is the second time we need
> to fix this because somebody thought the cast was unnecessary.
>
> Anyway the patch is Reviewed-by: Christian K?nig
> <christian.koenig@amd•com> and I'm going to keep an eye open for the
> next time somebody tries to remove this.
We use
static inline void __user *to_user_ptr(u64 address)
{
return (void __user *)(uintptr_t)address;
}
to make the intention clear and hide the cast from prying eyes.
-Chris
--
Chris Wilson, Intel Open Source Technology Centre
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH] drm/amdgpu: fix 32-bit compiler warning
2015-10-07 9:18 ` Arnd Bergmann
@ 2015-10-07 14:00 ` Alex Deucher
0 siblings, 0 replies; 5+ messages in thread
From: Alex Deucher @ 2015-10-07 14:00 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, Oct 7, 2015 at 5:18 AM, Arnd Bergmann <arnd@arndb•de> wrote:
> On Wednesday 07 October 2015 10:57:11 Christian K?nig wrote:
>> On 07.10.2015 09:41, Arnd Bergmann wrote:
>> > The new amdgpu driver passes a user space pointer in a 64-bit structure
>> > member, which is the correct way to do it, but it attempts to
>> > directly cast it to a __user pointer in the kernel, which causes
>> > a warning in three places:
>> >
>> > drm/amd/amdgpu/amdgpu_cs.c: In function 'amdgpu_cs_parser_init':
>> > drm/amd/amdgpu/amdgpu_cs.c:180:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
>> > chunk_array_user = (uint64_t __user *)(cs->in.chunks);
>> >
>> > This changes all three to add an intermediate cast to 'unsigned long'
>> > as other drivers do. This avoids the warning and works correctly on
>> > both 32-bit and 64-bit architectures.
>> >
>> > Signed-off-by: Arnd Bergmann <arnd@arndb•de>
>>
>> Well if I'm not completely mistaken this is the second time we need to
>> fix this because somebody thought the cast was unnecessary.
>>
>> Anyway the patch is Reviewed-by: Christian K?nig
>> <christian.koenig@amd•com> and I'm going to keep an eye open for the
>> next time somebody tries to remove this.
>>
>
> Ok, thanks.
>
> I guess I should have added
>
> Fixes: e60b344f6c0eff ("drm/amdgpu: optimize amdgpu_parser_init")
Applied this that comment added.
Thanks!
Alex
>
> Arnd
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel
^ permalink raw reply [flat|nested] 5+ messages in thread
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2015-10-07 7:41 [PATCH] drm/amdgpu: fix 32-bit compiler warning Arnd Bergmann
2015-10-07 8:57 ` Christian König
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2015-10-07 14:00 ` Alex Deucher
2015-10-07 9:21 ` Chris Wilson
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