* [PATCH] vboxvideo: Fix incorrect type in assignment sparse warning
@ 2017-12-25 14:42 Alexander Kapshuk
2018-01-06 14:20 ` Alexander Kapshuk
0 siblings, 1 reply; 8+ messages in thread
From: Alexander Kapshuk @ 2017-12-25 14:42 UTC (permalink / raw)
To: gregkh, hdegoede, michael.thayer, dri-devel
Cc: peda, daniel.vetter, cakturk, seanpaul, linux-kernel,
alexander.kapshuk
Sparse emitted the following warning:
../drivers/staging/vboxvideo/vbox_fb.c:173:27: warning: incorrect type in assignment (different address spaces)
../drivers/staging/vboxvideo/vbox_fb.c:173:27: expected char [noderef] <asn:2>*screen_base
../drivers/staging/vboxvideo/vbox_fb.c:173:27: got void *virtual
The vbox_bo buffer object kernel mapping is handled by a call
to ttm_bo_kmap() prior to the assignment of bo->kmap.virtual to
info->screen_base of type char __iomem*.
Casting bo->kmap.virtual to char __iomem* in this assignment fixes
the warning.
vboxvideo: Fix address space of expression removal sparse warning
Sparse emitted the following warning:
../drivers/staging/vboxvideo/vbox_main.c:64:25: warning: cast removes address space of expression
vbox->vbva_buffers iomapping is handled by calling vbox_accel_init()
from vbox_hw_init().
__force attribute is used in assignment to vbva to fix the warning.
Signed-off-by: Alexander Kapshuk <alexander.kapshuk@gmail.com>
---
drivers/staging/vboxvideo/vbox_fb.c | 2 +-
drivers/staging/vboxvideo/vbox_main.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/vboxvideo/vbox_fb.c b/drivers/staging/vboxvideo/vbox_fb.c
index 8aed248db6e2..43c39eca4ae1 100644
--- a/drivers/staging/vboxvideo/vbox_fb.c
+++ b/drivers/staging/vboxvideo/vbox_fb.c
@@ -170,7 +170,7 @@ static int vboxfb_create(struct drm_fb_helper *helper,
drm_fb_helper_fill_var(info, &fbdev->helper, sizes->fb_width,
sizes->fb_height);
- info->screen_base = bo->kmap.virtual;
+ info->screen_base = (char __iomem *)bo->kmap.virtual;
info->screen_size = size;
#ifdef CONFIG_DRM_KMS_FB_HELPER
diff --git a/drivers/staging/vboxvideo/vbox_main.c b/drivers/staging/vboxvideo/vbox_main.c
index 80bd039fa08e..973b3bcc04b1 100644
--- a/drivers/staging/vboxvideo/vbox_main.c
+++ b/drivers/staging/vboxvideo/vbox_main.c
@@ -61,7 +61,7 @@ void vbox_enable_accel(struct vbox_private *vbox)
if (vbox->vbva_info[i].vbva)
continue;
- vbva = (void *)vbox->vbva_buffers + i * VBVA_MIN_BUFFER_SIZE;
+ vbva = (void __force *)vbox->vbva_buffers + i * VBVA_MIN_BUFFER_SIZE;
if (!vbva_enable(&vbox->vbva_info[i],
vbox->guest_pool, vbva, i)) {
/* very old host or driver error. */
--
2.13.6
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH] vboxvideo: Fix incorrect type in assignment sparse warning
2017-12-25 14:42 [PATCH] vboxvideo: Fix incorrect type in assignment sparse warning Alexander Kapshuk
@ 2018-01-06 14:20 ` Alexander Kapshuk
2018-01-06 16:00 ` Hans de Goede
0 siblings, 1 reply; 8+ messages in thread
From: Alexander Kapshuk @ 2018-01-06 14:20 UTC (permalink / raw)
To: gregkh, hdegoede, michael.thayer, dri-devel
Cc: peda, daniel.vetter, cakturk, seanpaul, linux-kernel,
alexander.kapshuk
On Mon, Dec 25, 2017 at 04:42:59PM +0200, Alexander Kapshuk wrote:
> Sparse emitted the following warning:
> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: warning: incorrect type in assignment (different address spaces)
> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: expected char [noderef] <asn:2>*screen_base
> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: got void *virtual
>
> The vbox_bo buffer object kernel mapping is handled by a call
> to ttm_bo_kmap() prior to the assignment of bo->kmap.virtual to
> info->screen_base of type char __iomem*.
> Casting bo->kmap.virtual to char __iomem* in this assignment fixes
> the warning.
>
> vboxvideo: Fix address space of expression removal sparse warning
>
> Sparse emitted the following warning:
> ../drivers/staging/vboxvideo/vbox_main.c:64:25: warning: cast removes address space of expression
>
> vbox->vbva_buffers iomapping is handled by calling vbox_accel_init()
> from vbox_hw_init().
> __force attribute is used in assignment to vbva to fix the warning.
>
> Signed-off-by: Alexander Kapshuk <alexander.kapshuk@gmail.com>
> ---
> drivers/staging/vboxvideo/vbox_fb.c | 2 +-
> drivers/staging/vboxvideo/vbox_main.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/vboxvideo/vbox_fb.c b/drivers/staging/vboxvideo/vbox_fb.c
> index 8aed248db6e2..43c39eca4ae1 100644
> --- a/drivers/staging/vboxvideo/vbox_fb.c
> +++ b/drivers/staging/vboxvideo/vbox_fb.c
> @@ -170,7 +170,7 @@ static int vboxfb_create(struct drm_fb_helper *helper,
> drm_fb_helper_fill_var(info, &fbdev->helper, sizes->fb_width,
> sizes->fb_height);
>
> - info->screen_base = bo->kmap.virtual;
> + info->screen_base = (char __iomem *)bo->kmap.virtual;
> info->screen_size = size;
>
> #ifdef CONFIG_DRM_KMS_FB_HELPER
> diff --git a/drivers/staging/vboxvideo/vbox_main.c b/drivers/staging/vboxvideo/vbox_main.c
> index 80bd039fa08e..973b3bcc04b1 100644
> --- a/drivers/staging/vboxvideo/vbox_main.c
> +++ b/drivers/staging/vboxvideo/vbox_main.c
> @@ -61,7 +61,7 @@ void vbox_enable_accel(struct vbox_private *vbox)
> if (vbox->vbva_info[i].vbva)
> continue;
>
> - vbva = (void *)vbox->vbva_buffers + i * VBVA_MIN_BUFFER_SIZE;
> + vbva = (void __force *)vbox->vbva_buffers + i * VBVA_MIN_BUFFER_SIZE;
> if (!vbva_enable(&vbox->vbva_info[i],
> vbox->guest_pool, vbva, i)) {
> /* very old host or driver error. */
> --
> 2.13.6
>
Ping.
Could someone please comment on the patch above?
Thanks.
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] vboxvideo: Fix incorrect type in assignment sparse warning
2018-01-06 14:20 ` Alexander Kapshuk
@ 2018-01-06 16:00 ` Hans de Goede
0 siblings, 0 replies; 8+ messages in thread
From: Hans de Goede @ 2018-01-06 16:00 UTC (permalink / raw)
To: Alexander Kapshuk, gregkh, michael.thayer, dri-devel
Cc: peda, daniel.vetter, cakturk, seanpaul, linux-kernel
Hi,
On 06-01-18 15:20, Alexander Kapshuk wrote:
> On Mon, Dec 25, 2017 at 04:42:59PM +0200, Alexander Kapshuk wrote:
>> Sparse emitted the following warning:
>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: warning: incorrect type in assignment (different address spaces)
>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: expected char [noderef] <asn:2>*screen_base
>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: got void *virtual
>>
>> The vbox_bo buffer object kernel mapping is handled by a call
>> to ttm_bo_kmap() prior to the assignment of bo->kmap.virtual to
>> info->screen_base of type char __iomem*.
>> Casting bo->kmap.virtual to char __iomem* in this assignment fixes
>> the warning.
>>
>> vboxvideo: Fix address space of expression removal sparse warning
>>
>> Sparse emitted the following warning:
>> ../drivers/staging/vboxvideo/vbox_main.c:64:25: warning: cast removes address space of expression
>>
>> vbox->vbva_buffers iomapping is handled by calling vbox_accel_init()
>> from vbox_hw_init().
>> __force attribute is used in assignment to vbva to fix the warning.
>>
>> Signed-off-by: Alexander Kapshuk <alexander.kapshuk@gmail.com>
>> ---
>> drivers/staging/vboxvideo/vbox_fb.c | 2 +-
>> drivers/staging/vboxvideo/vbox_main.c | 2 +-
>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/staging/vboxvideo/vbox_fb.c b/drivers/staging/vboxvideo/vbox_fb.c
>> index 8aed248db6e2..43c39eca4ae1 100644
>> --- a/drivers/staging/vboxvideo/vbox_fb.c
>> +++ b/drivers/staging/vboxvideo/vbox_fb.c
>> @@ -170,7 +170,7 @@ static int vboxfb_create(struct drm_fb_helper *helper,
>> drm_fb_helper_fill_var(info, &fbdev->helper, sizes->fb_width,
>> sizes->fb_height);
>>
>> - info->screen_base = bo->kmap.virtual;
>> + info->screen_base = (char __iomem *)bo->kmap.virtual;
>> info->screen_size = size;
>>
>> #ifdef CONFIG_DRM_KMS_FB_HELPER
This fix looks good to me.
>> diff --git a/drivers/staging/vboxvideo/vbox_main.c b/drivers/staging/vboxvideo/vbox_main.c
>> index 80bd039fa08e..973b3bcc04b1 100644
>> --- a/drivers/staging/vboxvideo/vbox_main.c
>> +++ b/drivers/staging/vboxvideo/vbox_main.c
>> @@ -61,7 +61,7 @@ void vbox_enable_accel(struct vbox_private *vbox)
>> if (vbox->vbva_info[i].vbva)
>> continue;
>>
>> - vbva = (void *)vbox->vbva_buffers + i * VBVA_MIN_BUFFER_SIZE;
>> + vbva = (void __force *)vbox->vbva_buffers + i * VBVA_MIN_BUFFER_SIZE;
>> if (!vbva_enable(&vbox->vbva_info[i],
>> vbox->guest_pool, vbva, i)) {
>> /* very old host or driver error. */
Hmm, isn't there a cleaner way to fix this ? Maybe make vbva_enable's
argument (and the local vbva variable) of type u8 __iomem * too ?
Regards,
Hans
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH] vboxvideo: Fix incorrect type in assignment sparse warning
@ 2018-01-06 19:30 Alexander Kapshuk
2018-01-06 19:43 ` Hans de Goede
0 siblings, 1 reply; 8+ messages in thread
From: Alexander Kapshuk @ 2018-01-06 19:30 UTC (permalink / raw)
To: Hans de Goede
Cc: Greg KH, michael.thayer, dri-devel, peda, Daniel Vetter,
Cihangir Aktürk, Sean Paul, linux-kernel
On Sat, Jan 6, 2018 at 6:00 PM, Hans de Goede <hdegoede@redhat.com> wrote:
> Hi,
>
>
> On 06-01-18 15:20, Alexander Kapshuk wrote:
>>
>> On Mon, Dec 25, 2017 at 04:42:59PM +0200, Alexander Kapshuk wrote:
>>>
>>> Sparse emitted the following warning:
>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: warning: incorrect type in
>>> assignment (different address spaces)
>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: expected char [noderef]
>>> <asn:2>*screen_base
>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: got void *virtual
>>>
>>> The vbox_bo buffer object kernel mapping is handled by a call
>>> to ttm_bo_kmap() prior to the assignment of bo->kmap.virtual to
>>> info->screen_base of type char __iomem*.
>>> Casting bo->kmap.virtual to char __iomem* in this assignment fixes
>>> the warning.
>>>
>>> vboxvideo: Fix address space of expression removal sparse warning
>>>
>>> Sparse emitted the following warning:
>>> ../drivers/staging/vboxvideo/vbox_main.c:64:25: warning: cast removes
>>> address space of expression
>>>
>>> vbox->vbva_buffers iomapping is handled by calling vbox_accel_init()
>>> from vbox_hw_init().
>>> __force attribute is used in assignment to vbva to fix the warning.
>>>
>>> Signed-off-by: Alexander Kapshuk <alexander.kapshuk@gmail.com>
>>> ---
>>> drivers/staging/vboxvideo/vbox_fb.c | 2 +-
>>> drivers/staging/vboxvideo/vbox_main.c | 2 +-
>>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/staging/vboxvideo/vbox_fb.c
>>> b/drivers/staging/vboxvideo/vbox_fb.c
>>> index 8aed248db6e2..43c39eca4ae1 100644
>>> --- a/drivers/staging/vboxvideo/vbox_fb.c
>>> +++ b/drivers/staging/vboxvideo/vbox_fb.c
>>> @@ -170,7 +170,7 @@ static int vboxfb_create(struct drm_fb_helper
>>> *helper,
>>> drm_fb_helper_fill_var(info, &fbdev->helper, sizes->fb_width,
>>> sizes->fb_height);
>>>
>>> - info->screen_base = bo->kmap.virtual;
>>> + info->screen_base = (char __iomem *)bo->kmap.virtual;
>>> info->screen_size = size;
>>>
>>> #ifdef CONFIG_DRM_KMS_FB_HELPER
>
>
> This fix looks good to me.
>
>>> diff --git a/drivers/staging/vboxvideo/vbox_main.c
>>> b/drivers/staging/vboxvideo/vbox_main.c
>>> index 80bd039fa08e..973b3bcc04b1 100644
>>> --- a/drivers/staging/vboxvideo/vbox_main.c
>>> +++ b/drivers/staging/vboxvideo/vbox_main.c
>>> @@ -61,7 +61,7 @@ void vbox_enable_accel(struct vbox_private *vbox)
>>> if (vbox->vbva_info[i].vbva)
>>> continue;
>>>
>>> - vbva = (void *)vbox->vbva_buffers + i *
>>> VBVA_MIN_BUFFER_SIZE;
>>> + vbva = (void __force *)vbox->vbva_buffers + i *
>>> VBVA_MIN_BUFFER_SIZE;
>>> if (!vbva_enable(&vbox->vbva_info[i],
>>> vbox->guest_pool, vbva, i)) {
>>> /* very old host or driver error. */
>
>
> Hmm, isn't there a cleaner way to fix this ? Maybe make vbva_enable's
> argument (and the local vbva variable) of type u8 __iomem * too ?
>
> Regards,
>
> Hans
Hi Hans,
Thanks for your prompt response.
I had a good look at the vbva_enable() function's definition and to
the best of my knowledge, changing vbva's type from 'struct
vbva_buffer *' to 'u8 __iomem *' wouldn't work.
vbva_enable() relies on vbva's type being a pointer to 'struct vbva_buffer':
vbva's memory gets set to zero;
some of vbva's members are initialised to particular values;
vbva_ctx->vbva expects vbva to be a pointer to 'struct vbva_buffer' as well;
Or am I misreading this?
What are your thoughts on this?
Thanks.
Alexander.
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] vboxvideo: Fix incorrect type in assignment sparse warning
2018-01-06 19:30 Alexander Kapshuk
@ 2018-01-06 19:43 ` Hans de Goede
2018-01-06 19:56 ` Alexander Kapshuk
0 siblings, 1 reply; 8+ messages in thread
From: Hans de Goede @ 2018-01-06 19:43 UTC (permalink / raw)
To: Alexander Kapshuk
Cc: Greg KH, michael.thayer, dri-devel, peda, Daniel Vetter,
Cihangir Aktürk, Sean Paul, linux-kernel
HI,
On 06-01-18 20:30, Alexander Kapshuk wrote:
> On Sat, Jan 6, 2018 at 6:00 PM, Hans de Goede <hdegoede@redhat.com> wrote:
>> Hi,
>>
>>
>> On 06-01-18 15:20, Alexander Kapshuk wrote:
>>>
>>> On Mon, Dec 25, 2017 at 04:42:59PM +0200, Alexander Kapshuk wrote:
>>>>
>>>> Sparse emitted the following warning:
>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: warning: incorrect type in
>>>> assignment (different address spaces)
>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: expected char [noderef]
>>>> <asn:2>*screen_base
>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: got void *virtual
>>>>
>>>> The vbox_bo buffer object kernel mapping is handled by a call
>>>> to ttm_bo_kmap() prior to the assignment of bo->kmap.virtual to
>>>> info->screen_base of type char __iomem*.
>>>> Casting bo->kmap.virtual to char __iomem* in this assignment fixes
>>>> the warning.
>>>>
>>>> vboxvideo: Fix address space of expression removal sparse warning
>>>>
>>>> Sparse emitted the following warning:
>>>> ../drivers/staging/vboxvideo/vbox_main.c:64:25: warning: cast removes
>>>> address space of expression
>>>>
>>>> vbox->vbva_buffers iomapping is handled by calling vbox_accel_init()
>>>> from vbox_hw_init().
>>>> __force attribute is used in assignment to vbva to fix the warning.
>>>>
>>>> Signed-off-by: Alexander Kapshuk <alexander.kapshuk@gmail.com>
>>>> ---
>>>> drivers/staging/vboxvideo/vbox_fb.c | 2 +-
>>>> drivers/staging/vboxvideo/vbox_main.c | 2 +-
>>>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/drivers/staging/vboxvideo/vbox_fb.c
>>>> b/drivers/staging/vboxvideo/vbox_fb.c
>>>> index 8aed248db6e2..43c39eca4ae1 100644
>>>> --- a/drivers/staging/vboxvideo/vbox_fb.c
>>>> +++ b/drivers/staging/vboxvideo/vbox_fb.c
>>>> @@ -170,7 +170,7 @@ static int vboxfb_create(struct drm_fb_helper
>>>> *helper,
>>>> drm_fb_helper_fill_var(info, &fbdev->helper, sizes->fb_width,
>>>> sizes->fb_height);
>>>>
>>>> - info->screen_base = bo->kmap.virtual;
>>>> + info->screen_base = (char __iomem *)bo->kmap.virtual;
>>>> info->screen_size = size;
>>>>
>>>> #ifdef CONFIG_DRM_KMS_FB_HELPER
>>
>>
>> This fix looks good to me.
>>
>>>> diff --git a/drivers/staging/vboxvideo/vbox_main.c
>>>> b/drivers/staging/vboxvideo/vbox_main.c
>>>> index 80bd039fa08e..973b3bcc04b1 100644
>>>> --- a/drivers/staging/vboxvideo/vbox_main.c
>>>> +++ b/drivers/staging/vboxvideo/vbox_main.c
>>>> @@ -61,7 +61,7 @@ void vbox_enable_accel(struct vbox_private *vbox)
>>>> if (vbox->vbva_info[i].vbva)
>>>> continue;
>>>>
>>>> - vbva = (void *)vbox->vbva_buffers + i *
>>>> VBVA_MIN_BUFFER_SIZE;
>>>> + vbva = (void __force *)vbox->vbva_buffers + i *
>>>> VBVA_MIN_BUFFER_SIZE;
>>>> if (!vbva_enable(&vbox->vbva_info[i],
>>>> vbox->guest_pool, vbva, i)) {
>>>> /* very old host or driver error. */
>>
>>
>> Hmm, isn't there a cleaner way to fix this ? Maybe make vbva_enable's
>> argument (and the local vbva variable) of type u8 __iomem * too ?
>>
>> Regards,
>>
>> Hans
>
> Hi Hans,
>
> Thanks for your prompt response.
>
> I had a good look at the vbva_enable() function's definition and to
> the best of my knowledge, changing vbva's type from 'struct
> vbva_buffer *' to 'u8 __iomem *' wouldn't work.
> vbva_enable() relies on vbva's type being a pointer to 'struct vbva_buffer':
> vbva's memory gets set to zero;
> some of vbva's members are initialised to particular values;
> vbva_ctx->vbva expects vbva to be a pointer to 'struct vbva_buffer' as well;
>
> Or am I misreading this?
No your not misreading this I did not check the function myself before
commenting myself, my bad.
> What are your thoughts on this?
Lets just move ahead with your original fix:
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Regards,
Hans
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] vboxvideo: Fix incorrect type in assignment sparse warning
2018-01-06 19:43 ` Hans de Goede
@ 2018-01-06 19:56 ` Alexander Kapshuk
2018-01-06 20:00 ` Hans de Goede
0 siblings, 1 reply; 8+ messages in thread
From: Alexander Kapshuk @ 2018-01-06 19:56 UTC (permalink / raw)
To: Hans de Goede
Cc: Greg KH, michael.thayer, dri-devel, peda, Daniel Vetter,
Cihangir Aktürk, Sean Paul, linux-kernel
On Sat, Jan 6, 2018 at 9:43 PM, Hans de Goede <hdegoede@redhat.com> wrote:
> HI,
>
>
> On 06-01-18 20:30, Alexander Kapshuk wrote:
>>
>> On Sat, Jan 6, 2018 at 6:00 PM, Hans de Goede <hdegoede@redhat.com> wrote:
>>>
>>> Hi,
>>>
>>>
>>> On 06-01-18 15:20, Alexander Kapshuk wrote:
>>>>
>>>>
>>>> On Mon, Dec 25, 2017 at 04:42:59PM +0200, Alexander Kapshuk wrote:
>>>>>
>>>>>
>>>>> Sparse emitted the following warning:
>>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: warning: incorrect type
>>>>> in
>>>>> assignment (different address spaces)
>>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: expected char
>>>>> [noderef]
>>>>> <asn:2>*screen_base
>>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: got void *virtual
>>>>>
>>>>> The vbox_bo buffer object kernel mapping is handled by a call
>>>>> to ttm_bo_kmap() prior to the assignment of bo->kmap.virtual to
>>>>> info->screen_base of type char __iomem*.
>>>>> Casting bo->kmap.virtual to char __iomem* in this assignment fixes
>>>>> the warning.
>>>>>
>>>>> vboxvideo: Fix address space of expression removal sparse warning
>>>>>
>>>>> Sparse emitted the following warning:
>>>>> ../drivers/staging/vboxvideo/vbox_main.c:64:25: warning: cast removes
>>>>> address space of expression
>>>>>
>>>>> vbox->vbva_buffers iomapping is handled by calling vbox_accel_init()
>>>>> from vbox_hw_init().
>>>>> __force attribute is used in assignment to vbva to fix the warning.
>>>>>
>>>>> Signed-off-by: Alexander Kapshuk <alexander.kapshuk@gmail.com>
>>>>> ---
>>>>> drivers/staging/vboxvideo/vbox_fb.c | 2 +-
>>>>> drivers/staging/vboxvideo/vbox_main.c | 2 +-
>>>>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>>>>
>>>>> diff --git a/drivers/staging/vboxvideo/vbox_fb.c
>>>>> b/drivers/staging/vboxvideo/vbox_fb.c
>>>>> index 8aed248db6e2..43c39eca4ae1 100644
>>>>> --- a/drivers/staging/vboxvideo/vbox_fb.c
>>>>> +++ b/drivers/staging/vboxvideo/vbox_fb.c
>>>>> @@ -170,7 +170,7 @@ static int vboxfb_create(struct drm_fb_helper
>>>>> *helper,
>>>>> drm_fb_helper_fill_var(info, &fbdev->helper, sizes->fb_width,
>>>>> sizes->fb_height);
>>>>>
>>>>> - info->screen_base = bo->kmap.virtual;
>>>>> + info->screen_base = (char __iomem *)bo->kmap.virtual;
>>>>> info->screen_size = size;
>>>>>
>>>>> #ifdef CONFIG_DRM_KMS_FB_HELPER
>>>
>>>
>>>
>>> This fix looks good to me.
>>>
>>>>> diff --git a/drivers/staging/vboxvideo/vbox_main.c
>>>>> b/drivers/staging/vboxvideo/vbox_main.c
>>>>> index 80bd039fa08e..973b3bcc04b1 100644
>>>>> --- a/drivers/staging/vboxvideo/vbox_main.c
>>>>> +++ b/drivers/staging/vboxvideo/vbox_main.c
>>>>> @@ -61,7 +61,7 @@ void vbox_enable_accel(struct vbox_private *vbox)
>>>>> if (vbox->vbva_info[i].vbva)
>>>>> continue;
>>>>>
>>>>> - vbva = (void *)vbox->vbva_buffers + i *
>>>>> VBVA_MIN_BUFFER_SIZE;
>>>>> + vbva = (void __force *)vbox->vbva_buffers + i *
>>>>> VBVA_MIN_BUFFER_SIZE;
>>>>> if (!vbva_enable(&vbox->vbva_info[i],
>>>>> vbox->guest_pool, vbva, i)) {
>>>>> /* very old host or driver error. */
>>>
>>>
>>>
>>> Hmm, isn't there a cleaner way to fix this ? Maybe make vbva_enable's
>>> argument (and the local vbva variable) of type u8 __iomem * too ?
>>>
>>> Regards,
>>>
>>> Hans
>>
>>
>> Hi Hans,
>>
>> Thanks for your prompt response.
>>
>> I had a good look at the vbva_enable() function's definition and to
>> the best of my knowledge, changing vbva's type from 'struct
>> vbva_buffer *' to 'u8 __iomem *' wouldn't work.
>> vbva_enable() relies on vbva's type being a pointer to 'struct
>> vbva_buffer':
>> vbva's memory gets set to zero;
>> some of vbva's members are initialised to particular values;
>> vbva_ctx->vbva expects vbva to be a pointer to 'struct vbva_buffer' as
>> well;
>>
>> Or am I misreading this?
>
>
> No your not misreading this I did not check the function myself before
> commenting myself, my bad.
Thanks for confirming my understanding of this.
>
>> What are your thoughts on this?
>
>
> Lets just move ahead with your original fix:
Did you want me to resend the patch, or is someone going to pull the
original one I sent into their tree?
Thanks.
>
> Reviewed-by: Hans de Goede <hdegoede@redhat.com>
>
> Regards,
>
> Hans
>
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] vboxvideo: Fix incorrect type in assignment sparse warning
2018-01-06 19:56 ` Alexander Kapshuk
@ 2018-01-06 20:00 ` Hans de Goede
2018-01-06 20:02 ` Alexander Kapshuk
0 siblings, 1 reply; 8+ messages in thread
From: Hans de Goede @ 2018-01-06 20:00 UTC (permalink / raw)
To: Alexander Kapshuk
Cc: Greg KH, michael.thayer, dri-devel, peda, Daniel Vetter,
Cihangir Aktürk, Sean Paul, linux-kernel
Hi,
On 06-01-18 20:56, Alexander Kapshuk wrote:
> On Sat, Jan 6, 2018 at 9:43 PM, Hans de Goede <hdegoede@redhat.com> wrote:
>> HI,
>>
>>
>> On 06-01-18 20:30, Alexander Kapshuk wrote:
>>>
>>> On Sat, Jan 6, 2018 at 6:00 PM, Hans de Goede <hdegoede@redhat.com> wrote:
>>>>
>>>> Hi,
>>>>
>>>>
>>>> On 06-01-18 15:20, Alexander Kapshuk wrote:
>>>>>
>>>>>
>>>>> On Mon, Dec 25, 2017 at 04:42:59PM +0200, Alexander Kapshuk wrote:
>>>>>>
>>>>>>
>>>>>> Sparse emitted the following warning:
>>>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: warning: incorrect type
>>>>>> in
>>>>>> assignment (different address spaces)
>>>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: expected char
>>>>>> [noderef]
>>>>>> <asn:2>*screen_base
>>>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: got void *virtual
>>>>>>
>>>>>> The vbox_bo buffer object kernel mapping is handled by a call
>>>>>> to ttm_bo_kmap() prior to the assignment of bo->kmap.virtual to
>>>>>> info->screen_base of type char __iomem*.
>>>>>> Casting bo->kmap.virtual to char __iomem* in this assignment fixes
>>>>>> the warning.
>>>>>>
>>>>>> vboxvideo: Fix address space of expression removal sparse warning
>>>>>>
>>>>>> Sparse emitted the following warning:
>>>>>> ../drivers/staging/vboxvideo/vbox_main.c:64:25: warning: cast removes
>>>>>> address space of expression
>>>>>>
>>>>>> vbox->vbva_buffers iomapping is handled by calling vbox_accel_init()
>>>>>> from vbox_hw_init().
>>>>>> __force attribute is used in assignment to vbva to fix the warning.
>>>>>>
>>>>>> Signed-off-by: Alexander Kapshuk <alexander.kapshuk@gmail.com>
>>>>>> ---
>>>>>> drivers/staging/vboxvideo/vbox_fb.c | 2 +-
>>>>>> drivers/staging/vboxvideo/vbox_main.c | 2 +-
>>>>>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>>>>>
>>>>>> diff --git a/drivers/staging/vboxvideo/vbox_fb.c
>>>>>> b/drivers/staging/vboxvideo/vbox_fb.c
>>>>>> index 8aed248db6e2..43c39eca4ae1 100644
>>>>>> --- a/drivers/staging/vboxvideo/vbox_fb.c
>>>>>> +++ b/drivers/staging/vboxvideo/vbox_fb.c
>>>>>> @@ -170,7 +170,7 @@ static int vboxfb_create(struct drm_fb_helper
>>>>>> *helper,
>>>>>> drm_fb_helper_fill_var(info, &fbdev->helper, sizes->fb_width,
>>>>>> sizes->fb_height);
>>>>>>
>>>>>> - info->screen_base = bo->kmap.virtual;
>>>>>> + info->screen_base = (char __iomem *)bo->kmap.virtual;
>>>>>> info->screen_size = size;
>>>>>>
>>>>>> #ifdef CONFIG_DRM_KMS_FB_HELPER
>>>>
>>>>
>>>>
>>>> This fix looks good to me.
>>>>
>>>>>> diff --git a/drivers/staging/vboxvideo/vbox_main.c
>>>>>> b/drivers/staging/vboxvideo/vbox_main.c
>>>>>> index 80bd039fa08e..973b3bcc04b1 100644
>>>>>> --- a/drivers/staging/vboxvideo/vbox_main.c
>>>>>> +++ b/drivers/staging/vboxvideo/vbox_main.c
>>>>>> @@ -61,7 +61,7 @@ void vbox_enable_accel(struct vbox_private *vbox)
>>>>>> if (vbox->vbva_info[i].vbva)
>>>>>> continue;
>>>>>>
>>>>>> - vbva = (void *)vbox->vbva_buffers + i *
>>>>>> VBVA_MIN_BUFFER_SIZE;
>>>>>> + vbva = (void __force *)vbox->vbva_buffers + i *
>>>>>> VBVA_MIN_BUFFER_SIZE;
>>>>>> if (!vbva_enable(&vbox->vbva_info[i],
>>>>>> vbox->guest_pool, vbva, i)) {
>>>>>> /* very old host or driver error. */
>>>>
>>>>
>>>>
>>>> Hmm, isn't there a cleaner way to fix this ? Maybe make vbva_enable's
>>>> argument (and the local vbva variable) of type u8 __iomem * too ?
>>>>
>>>> Regards,
>>>>
>>>> Hans
>>>
>>>
>>> Hi Hans,
>>>
>>> Thanks for your prompt response.
>>>
>>> I had a good look at the vbva_enable() function's definition and to
>>> the best of my knowledge, changing vbva's type from 'struct
>>> vbva_buffer *' to 'u8 __iomem *' wouldn't work.
>>> vbva_enable() relies on vbva's type being a pointer to 'struct
>>> vbva_buffer':
>>> vbva's memory gets set to zero;
>>> some of vbva's members are initialised to particular values;
>>> vbva_ctx->vbva expects vbva to be a pointer to 'struct vbva_buffer' as
>>> well;
>>>
>>> Or am I misreading this?
>>
>>
>> No your not misreading this I did not check the function myself before
>> commenting myself, my bad.
>
> Thanks for confirming my understanding of this.
>
>>
>>> What are your thoughts on this?
>>
>>
>> Lets just move ahead with your original fix:
>
> Did you want me to resend the patch, or is someone going to pull the
> original one I sent into their tree?
> Thanks.
I expect Greg to pick it up without a resend. But with all the Spectre
stuff going on right now he might miss it, so I would say give it 14 days
and if he has not picked it up by then, resend it with my reviewed-by
added.
Regards,
Hans
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] vboxvideo: Fix incorrect type in assignment sparse warning
2018-01-06 20:00 ` Hans de Goede
@ 2018-01-06 20:02 ` Alexander Kapshuk
0 siblings, 0 replies; 8+ messages in thread
From: Alexander Kapshuk @ 2018-01-06 20:02 UTC (permalink / raw)
To: Hans de Goede
Cc: Greg KH, michael.thayer, dri-devel, peda, Daniel Vetter,
Cihangir Aktürk, Sean Paul, linux-kernel
On Sat, Jan 6, 2018 at 10:00 PM, Hans de Goede <hdegoede@redhat.com> wrote:
> Hi,
>
>
> On 06-01-18 20:56, Alexander Kapshuk wrote:
>>
>> On Sat, Jan 6, 2018 at 9:43 PM, Hans de Goede <hdegoede@redhat.com> wrote:
>>>
>>> HI,
>>>
>>>
>>> On 06-01-18 20:30, Alexander Kapshuk wrote:
>>>>
>>>>
>>>> On Sat, Jan 6, 2018 at 6:00 PM, Hans de Goede <hdegoede@redhat.com>
>>>> wrote:
>>>>>
>>>>>
>>>>> Hi,
>>>>>
>>>>>
>>>>> On 06-01-18 15:20, Alexander Kapshuk wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>> On Mon, Dec 25, 2017 at 04:42:59PM +0200, Alexander Kapshuk wrote:
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Sparse emitted the following warning:
>>>>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: warning: incorrect
>>>>>>> type
>>>>>>> in
>>>>>>> assignment (different address spaces)
>>>>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: expected char
>>>>>>> [noderef]
>>>>>>> <asn:2>*screen_base
>>>>>>> ../drivers/staging/vboxvideo/vbox_fb.c:173:27: got void *virtual
>>>>>>>
>>>>>>> The vbox_bo buffer object kernel mapping is handled by a call
>>>>>>> to ttm_bo_kmap() prior to the assignment of bo->kmap.virtual to
>>>>>>> info->screen_base of type char __iomem*.
>>>>>>> Casting bo->kmap.virtual to char __iomem* in this assignment fixes
>>>>>>> the warning.
>>>>>>>
>>>>>>> vboxvideo: Fix address space of expression removal sparse warning
>>>>>>>
>>>>>>> Sparse emitted the following warning:
>>>>>>> ../drivers/staging/vboxvideo/vbox_main.c:64:25: warning: cast removes
>>>>>>> address space of expression
>>>>>>>
>>>>>>> vbox->vbva_buffers iomapping is handled by calling vbox_accel_init()
>>>>>>> from vbox_hw_init().
>>>>>>> __force attribute is used in assignment to vbva to fix the warning.
>>>>>>>
>>>>>>> Signed-off-by: Alexander Kapshuk <alexander.kapshuk@gmail.com>
>>>>>>> ---
>>>>>>> drivers/staging/vboxvideo/vbox_fb.c | 2 +-
>>>>>>> drivers/staging/vboxvideo/vbox_main.c | 2 +-
>>>>>>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>>>>>>
>>>>>>> diff --git a/drivers/staging/vboxvideo/vbox_fb.c
>>>>>>> b/drivers/staging/vboxvideo/vbox_fb.c
>>>>>>> index 8aed248db6e2..43c39eca4ae1 100644
>>>>>>> --- a/drivers/staging/vboxvideo/vbox_fb.c
>>>>>>> +++ b/drivers/staging/vboxvideo/vbox_fb.c
>>>>>>> @@ -170,7 +170,7 @@ static int vboxfb_create(struct drm_fb_helper
>>>>>>> *helper,
>>>>>>> drm_fb_helper_fill_var(info, &fbdev->helper,
>>>>>>> sizes->fb_width,
>>>>>>> sizes->fb_height);
>>>>>>>
>>>>>>> - info->screen_base = bo->kmap.virtual;
>>>>>>> + info->screen_base = (char __iomem *)bo->kmap.virtual;
>>>>>>> info->screen_size = size;
>>>>>>>
>>>>>>> #ifdef CONFIG_DRM_KMS_FB_HELPER
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> This fix looks good to me.
>>>>>
>>>>>>> diff --git a/drivers/staging/vboxvideo/vbox_main.c
>>>>>>> b/drivers/staging/vboxvideo/vbox_main.c
>>>>>>> index 80bd039fa08e..973b3bcc04b1 100644
>>>>>>> --- a/drivers/staging/vboxvideo/vbox_main.c
>>>>>>> +++ b/drivers/staging/vboxvideo/vbox_main.c
>>>>>>> @@ -61,7 +61,7 @@ void vbox_enable_accel(struct vbox_private *vbox)
>>>>>>> if (vbox->vbva_info[i].vbva)
>>>>>>> continue;
>>>>>>>
>>>>>>> - vbva = (void *)vbox->vbva_buffers + i *
>>>>>>> VBVA_MIN_BUFFER_SIZE;
>>>>>>> + vbva = (void __force *)vbox->vbva_buffers + i *
>>>>>>> VBVA_MIN_BUFFER_SIZE;
>>>>>>> if (!vbva_enable(&vbox->vbva_info[i],
>>>>>>> vbox->guest_pool, vbva, i)) {
>>>>>>> /* very old host or driver error. */
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> Hmm, isn't there a cleaner way to fix this ? Maybe make vbva_enable's
>>>>> argument (and the local vbva variable) of type u8 __iomem * too ?
>>>>>
>>>>> Regards,
>>>>>
>>>>> Hans
>>>>
>>>>
>>>>
>>>> Hi Hans,
>>>>
>>>> Thanks for your prompt response.
>>>>
>>>> I had a good look at the vbva_enable() function's definition and to
>>>> the best of my knowledge, changing vbva's type from 'struct
>>>> vbva_buffer *' to 'u8 __iomem *' wouldn't work.
>>>> vbva_enable() relies on vbva's type being a pointer to 'struct
>>>> vbva_buffer':
>>>> vbva's memory gets set to zero;
>>>> some of vbva's members are initialised to particular values;
>>>> vbva_ctx->vbva expects vbva to be a pointer to 'struct vbva_buffer' as
>>>> well;
>>>>
>>>> Or am I misreading this?
>>>
>>>
>>>
>>> No your not misreading this I did not check the function myself before
>>> commenting myself, my bad.
>>
>>
>> Thanks for confirming my understanding of this.
>>
>>>
>>>> What are your thoughts on this?
>>>
>>>
>>>
>>> Lets just move ahead with your original fix:
>>
>>
>> Did you want me to resend the patch, or is someone going to pull the
>> original one I sent into their tree?
>> Thanks.
>
>
> I expect Greg to pick it up without a resend. But with all the Spectre
> stuff going on right now he might miss it, so I would say give it 14 days
> and if he has not picked it up by then, resend it with my reviewed-by
> added.
>
> Regards,
>
> Hans
Understood.
Thanks.
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2018-01-06 20:03 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
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2017-12-25 14:42 [PATCH] vboxvideo: Fix incorrect type in assignment sparse warning Alexander Kapshuk
2018-01-06 14:20 ` Alexander Kapshuk
2018-01-06 16:00 ` Hans de Goede
-- strict thread matches above, loose matches on Subject: below --
2018-01-06 19:30 Alexander Kapshuk
2018-01-06 19:43 ` Hans de Goede
2018-01-06 19:56 ` Alexander Kapshuk
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2018-01-06 20:02 ` Alexander Kapshuk
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