* [PATCH v3 26/26] kfifo: DECLARE_KIFO_PTR(fifo, u64) does not work on arm 32 bit
[not found] <cover.1507618840.git.sean@mess.org>
@ 2017-10-10 7:18 ` Sean Young
2017-10-10 7:59 ` Sean Young
1 sibling, 0 replies; 5+ messages in thread
From: Sean Young @ 2017-10-10 7:18 UTC (permalink / raw)
To: linux-media, linux-kernel, Stefani Seibold, Randy Dunlap; +Cc: Andrew Morton
If you try to store u64 in a kfifo (or a struct with u64 members),
then the buf member of __STRUCT_KFIFO_PTR will cause 4 bytes
padding due to alignment (note that struct __kfifo is 20 bytes
on 32 bit).
That in turn causes the __is_kfifo_ptr() to fail, which is caught
by kfifo_alloc(), which now returns EINVAL.
So, ensure that __is_kfifo_ptr() compares to the right structure.
Signed-off-by: Sean Young <sean@mess.org>
---
include/linux/kfifo.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/include/linux/kfifo.h b/include/linux/kfifo.h
index 41eb6fdf87a8..86b5fb08e96c 100644
--- a/include/linux/kfifo.h
+++ b/include/linux/kfifo.h
@@ -113,7 +113,8 @@ struct kfifo_rec_ptr_2 __STRUCT_KFIFO_PTR(unsigned char, 2, void);
* array is a part of the structure and the fifo type where the array is
* outside of the fifo structure.
*/
-#define __is_kfifo_ptr(fifo) (sizeof(*fifo) == sizeof(struct __kfifo))
+#define __is_kfifo_ptr(fifo) \
+ (sizeof(*fifo) == sizeof(STRUCT_KFIFO_PTR(typeof(*(fifo)->type))))
/**
* DECLARE_KFIFO_PTR - macro to declare a fifo pointer object
--
2.13.6
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH v3 26/26] kfifo: DECLARE_KIFO_PTR(fifo, u64) does not work on arm 32 bit
[not found] <cover.1507618840.git.sean@mess.org>
2017-10-10 7:18 ` [PATCH v3 26/26] kfifo: DECLARE_KIFO_PTR(fifo, u64) does not work on arm 32 bit Sean Young
@ 2017-10-10 7:59 ` Sean Young
2017-11-30 12:29 ` Mauro Carvalho Chehab
1 sibling, 1 reply; 5+ messages in thread
From: Sean Young @ 2017-10-10 7:59 UTC (permalink / raw)
To: linux-media, linux-kernel, Stefani Seibold, Randy Dunlap; +Cc: Andrew Morton
If you try to store u64 in a kfifo (or a struct with u64 members),
then the buf member of __STRUCT_KFIFO_PTR will cause 4 bytes
padding due to alignment (note that struct __kfifo is 20 bytes
on 32 bit).
That in turn causes the __is_kfifo_ptr() to fail, which is caught
by kfifo_alloc(), which now returns EINVAL.
So, ensure that __is_kfifo_ptr() compares to the right structure.
Signed-off-by: Sean Young <sean@mess.org>
Acked-by: Stefani Seibold <stefani@seibold.net>
---
include/linux/kfifo.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/include/linux/kfifo.h b/include/linux/kfifo.h
index 41eb6fdf87a8..86b5fb08e96c 100644
--- a/include/linux/kfifo.h
+++ b/include/linux/kfifo.h
@@ -113,7 +113,8 @@ struct kfifo_rec_ptr_2 __STRUCT_KFIFO_PTR(unsigned char, 2, void);
* array is a part of the structure and the fifo type where the array is
* outside of the fifo structure.
*/
-#define __is_kfifo_ptr(fifo) (sizeof(*fifo) == sizeof(struct __kfifo))
+#define __is_kfifo_ptr(fifo) \
+ (sizeof(*fifo) == sizeof(STRUCT_KFIFO_PTR(typeof(*(fifo)->type))))
/**
* DECLARE_KFIFO_PTR - macro to declare a fifo pointer object
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH v3 26/26] kfifo: DECLARE_KIFO_PTR(fifo, u64) does not work on arm 32 bit
2017-10-10 7:59 ` Sean Young
@ 2017-11-30 12:29 ` Mauro Carvalho Chehab
2017-11-30 12:34 ` Stefani Seibold
0 siblings, 1 reply; 5+ messages in thread
From: Mauro Carvalho Chehab @ 2017-11-30 12:29 UTC (permalink / raw)
To: Sean Young, Stefani Seibold, Andrew Morton
Cc: linux-media, linux-kernel, Randy Dunlap
Em Tue, 10 Oct 2017 09:59:42 +0200
Sean Young <sean@mess.org> escreveu:
> If you try to store u64 in a kfifo (or a struct with u64 members),
> then the buf member of __STRUCT_KFIFO_PTR will cause 4 bytes
> padding due to alignment (note that struct __kfifo is 20 bytes
> on 32 bit).
>
> That in turn causes the __is_kfifo_ptr() to fail, which is caught
> by kfifo_alloc(), which now returns EINVAL.
>
> So, ensure that __is_kfifo_ptr() compares to the right structure.
>
> Signed-off-by: Sean Young <sean@mess.org>
> Acked-by: Stefani Seibold <stefani@seibold.net>
Hi Stefani/Andrew,
As this patch is required for the LIRC rework, would be ok if I would
merge it via the media tree?
Thanks!
Mauro
>
> ---
> include/linux/kfifo.h | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/kfifo.h b/include/linux/kfifo.h
> index 41eb6fdf87a8..86b5fb08e96c 100644
> --- a/include/linux/kfifo.h
> +++ b/include/linux/kfifo.h
> @@ -113,7 +113,8 @@ struct kfifo_rec_ptr_2 __STRUCT_KFIFO_PTR(unsigned char, 2, void);
> * array is a part of the structure and the fifo type where the array is
> * outside of the fifo structure.
> */
> -#define __is_kfifo_ptr(fifo) (sizeof(*fifo) == sizeof(struct __kfifo))
> +#define __is_kfifo_ptr(fifo) \
> + (sizeof(*fifo) == sizeof(STRUCT_KFIFO_PTR(typeof(*(fifo)->type))))
>
> /**
> * DECLARE_KFIFO_PTR - macro to declare a fifo pointer object
Thanks,
Mauro
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v3 26/26] kfifo: DECLARE_KIFO_PTR(fifo, u64) does not work on arm 32 bit
2017-11-30 12:29 ` Mauro Carvalho Chehab
@ 2017-11-30 12:34 ` Stefani Seibold
2017-12-08 14:07 ` Mauro Carvalho Chehab
0 siblings, 1 reply; 5+ messages in thread
From: Stefani Seibold @ 2017-11-30 12:34 UTC (permalink / raw)
To: Mauro Carvalho Chehab, Sean Young, Andrew Morton
Cc: linux-media, linux-kernel, Randy Dunlap
On Thu, 2017-11-30 at 10:29 -0200, Mauro Carvalho Chehab wrote:
> Em Tue, 10 Oct 2017 09:59:42 +0200
> Sean Young <sean@mess.org> escreveu:
>
> > If you try to store u64 in a kfifo (or a struct with u64 members),
> > then the buf member of __STRUCT_KFIFO_PTR will cause 4 bytes
> > padding due to alignment (note that struct __kfifo is 20 bytes
> > on 32 bit).
> >
> > That in turn causes the __is_kfifo_ptr() to fail, which is caught
> > by kfifo_alloc(), which now returns EINVAL.
> >
> > So, ensure that __is_kfifo_ptr() compares to the right structure.
> >
> > Signed-off-by: Sean Young <sean@mess.org>
> > Acked-by: Stefani Seibold <stefani@seibold.net>
>
> Hi Stefani/Andrew,
>
> As this patch is required for the LIRC rework, would be ok if I would
> merge it via the media tree?
>
It is okay by me. But the question remains why this patch wasn't
already merged?
Andrew: Any objections against this patch?
> >
> > ---
> > include/linux/kfifo.h | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/include/linux/kfifo.h b/include/linux/kfifo.h
> > index 41eb6fdf87a8..86b5fb08e96c 100644
> > --- a/include/linux/kfifo.h
> > +++ b/include/linux/kfifo.h
> > @@ -113,7 +113,8 @@ struct kfifo_rec_ptr_2
> > __STRUCT_KFIFO_PTR(unsigned char, 2, void);
> > * array is a part of the structure and the fifo type where the
> > array is
> > * outside of the fifo structure.
> > */
> > -#define __is_kfifo_ptr(fifo) (sizeof(*fifo) ==
> > sizeof(struct __kfifo))
> > +#define __is_kfifo_ptr(fifo) \
> > + (sizeof(*fifo) == sizeof(STRUCT_KFIFO_PTR(typeof(*(fifo)-
> > >type))))
> >
> > /**
> > * DECLARE_KFIFO_PTR - macro to declare a fifo pointer object
>
>
>
> Thanks,
> Mauro
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v3 26/26] kfifo: DECLARE_KIFO_PTR(fifo, u64) does not work on arm 32 bit
2017-11-30 12:34 ` Stefani Seibold
@ 2017-12-08 14:07 ` Mauro Carvalho Chehab
0 siblings, 0 replies; 5+ messages in thread
From: Mauro Carvalho Chehab @ 2017-12-08 14:07 UTC (permalink / raw)
To: Stefani Seibold, Andrew Morton
Cc: Sean Young, linux-media, linux-kernel, Randy Dunlap
Em Thu, 30 Nov 2017 13:34:10 +0100
Stefani Seibold <stefani@seibold.net> escreveu:
> On Thu, 2017-11-30 at 10:29 -0200, Mauro Carvalho Chehab wrote:
> > Em Tue, 10 Oct 2017 09:59:42 +0200
> > Sean Young <sean@mess.org> escreveu:
> >
> > > If you try to store u64 in a kfifo (or a struct with u64 members),
> > > then the buf member of __STRUCT_KFIFO_PTR will cause 4 bytes
> > > padding due to alignment (note that struct __kfifo is 20 bytes
> > > on 32 bit).
> > >
> > > That in turn causes the __is_kfifo_ptr() to fail, which is caught
> > > by kfifo_alloc(), which now returns EINVAL.
> > >
> > > So, ensure that __is_kfifo_ptr() compares to the right structure.
> > >
> > > Signed-off-by: Sean Young <sean@mess.org>
> > > Acked-by: Stefani Seibold <stefani@seibold.net>
> >
> > Hi Stefani/Andrew,
> >
> > As this patch is required for the LIRC rework, would be ok if I would
> > merge it via the media tree?
> >
>
> It is okay by me. But the question remains why this patch wasn't
> already merged?
>
> Andrew: Any objections against this patch?
I'm assuming that merging via media tree is ok for Andrew. So, I guess
I'll just go ahead and merge it via my tree.
Thanks,
Mauro
^ permalink raw reply [flat|nested] 5+ messages in thread
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2017-10-10 7:18 ` [PATCH v3 26/26] kfifo: DECLARE_KIFO_PTR(fifo, u64) does not work on arm 32 bit Sean Young
2017-10-10 7:59 ` Sean Young
2017-11-30 12:29 ` Mauro Carvalho Chehab
2017-11-30 12:34 ` Stefani Seibold
2017-12-08 14:07 ` Mauro Carvalho Chehab
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