2019-04-01 23:51:09

by Stephen Rothwell

[permalink] [raw]
Subject: linux-next: build failure after merge of the drm-misc tree

Hi all,

After merging the drm-misc tree, today's linux-next build (x86_64
allmodconfig) failed like this:

In file included from include/linux/kernel.h:7,
from include/asm-generic/bug.h:18,
from arch/x86/include/asm/bug.h:83,
from include/linux/bug.h:5,
from include/linux/mmdebug.h:5,
from include/linux/gfp.h:5,
from include/linux/slab.h:15,
from drivers/gpu/drm/lima/lima_ctx.c:4:
drivers/gpu/drm/lima/lima_ctx.c: In function 'lima_ctx_create':
include/linux/limits.h:13:18: warning: passing argument 3 of 'xa_alloc' makes pointer from integer without a cast [-Wint-conversion]
#define UINT_MAX (~0U)
^~~~~
drivers/gpu/drm/lima/lima_ctx.c:26:36: note: in expansion of macro 'UINT_MAX'
err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
^~~~~~~~
In file included from include/linux/radix-tree.h:31,
from include/linux/idr.h:15,
from include/drm/drm_device.h:7,
from drivers/gpu/drm/lima/lima_device.h:7,
from drivers/gpu/drm/lima/lima_ctx.c:6:
include/linux/xarray.h:817:9: note: expected 'void *' but argument is of type 'unsigned int'
void *entry, struct xa_limit limit, gfp_t gfp)
~~~~~~^~~~~
drivers/gpu/drm/lima/lima_ctx.c:26:46: error: incompatible type for argument 4 of 'xa_alloc'
err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
^~~
In file included from include/linux/radix-tree.h:31,
from include/linux/idr.h:15,
from include/drm/drm_device.h:7,
from drivers/gpu/drm/lima/lima_device.h:7,
from drivers/gpu/drm/lima/lima_ctx.c:6:
include/linux/xarray.h:817:32: note: expected 'struct xa_limit' but argument is of type 'struct lima_ctx *'
void *entry, struct xa_limit limit, gfp_t gfp)
~~~~~~~~~~~~~~~~^~~~~

Caused by commit

a1d2a6339961 ("drm/lima: driver for ARM Mali4xx GPUs")

interacting with commit

a3e4d3f97ec8 ("XArray: Redesign xa_alloc API")

from Linus' tree (v5.1-rc1).

I have applied the following patch for today. It could be applied as
part of a merge of v5.1-rc1 into drm-misc.

From: Stephen Rothwell <[email protected]>
Date: Tue, 2 Apr 2019 10:45:32 +1100
Subject: [PATCH] drm/lima: update for xa_alloc API change

Signed-off-by: Stephen Rothwell <[email protected]>
---
drivers/gpu/drm/lima/lima_ctx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/lima/lima_ctx.c b/drivers/gpu/drm/lima/lima_ctx.c
index c8d12f7c6894..bafa00d74cc5 100644
--- a/drivers/gpu/drm/lima/lima_ctx.c
+++ b/drivers/gpu/drm/lima/lima_ctx.c
@@ -23,7 +23,7 @@ int lima_ctx_create(struct lima_device *dev, struct lima_ctx_mgr *mgr, u32 *id)
goto err_out0;
}

- err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
+ err = xa_alloc(&mgr->handles, id, ctx, XA_LIMIT(*id, UINT_MAX), GFP_KERNEL);
if (err < 0)
goto err_out0;

--
2.20.1

--
Cheers,
Stephen Rothwell


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2019-04-02 06:23:14

by Qiang Yu

[permalink] [raw]
Subject: Re: linux-next: build failure after merge of the drm-misc tree

Thanks, patch is:
Reviewed-by: Qiang Yu <[email protected]>

Regards,
Qiang

On Tue, Apr 2, 2019 at 7:50 AM Stephen Rothwell <[email protected]> wrote:
>
> Hi all,
>
> After merging the drm-misc tree, today's linux-next build (x86_64
> allmodconfig) failed like this:
>
> In file included from include/linux/kernel.h:7,
> from include/asm-generic/bug.h:18,
> from arch/x86/include/asm/bug.h:83,
> from include/linux/bug.h:5,
> from include/linux/mmdebug.h:5,
> from include/linux/gfp.h:5,
> from include/linux/slab.h:15,
> from drivers/gpu/drm/lima/lima_ctx.c:4:
> drivers/gpu/drm/lima/lima_ctx.c: In function 'lima_ctx_create':
> include/linux/limits.h:13:18: warning: passing argument 3 of 'xa_alloc' makes pointer from integer without a cast [-Wint-conversion]
> #define UINT_MAX (~0U)
> ^~~~~
> drivers/gpu/drm/lima/lima_ctx.c:26:36: note: in expansion of macro 'UINT_MAX'
> err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> ^~~~~~~~
> In file included from include/linux/radix-tree.h:31,
> from include/linux/idr.h:15,
> from include/drm/drm_device.h:7,
> from drivers/gpu/drm/lima/lima_device.h:7,
> from drivers/gpu/drm/lima/lima_ctx.c:6:
> include/linux/xarray.h:817:9: note: expected 'void *' but argument is of type 'unsigned int'
> void *entry, struct xa_limit limit, gfp_t gfp)
> ~~~~~~^~~~~
> drivers/gpu/drm/lima/lima_ctx.c:26:46: error: incompatible type for argument 4 of 'xa_alloc'
> err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> ^~~
> In file included from include/linux/radix-tree.h:31,
> from include/linux/idr.h:15,
> from include/drm/drm_device.h:7,
> from drivers/gpu/drm/lima/lima_device.h:7,
> from drivers/gpu/drm/lima/lima_ctx.c:6:
> include/linux/xarray.h:817:32: note: expected 'struct xa_limit' but argument is of type 'struct lima_ctx *'
> void *entry, struct xa_limit limit, gfp_t gfp)
> ~~~~~~~~~~~~~~~~^~~~~
>
> Caused by commit
>
> a1d2a6339961 ("drm/lima: driver for ARM Mali4xx GPUs")
>
> interacting with commit
>
> a3e4d3f97ec8 ("XArray: Redesign xa_alloc API")
>
> from Linus' tree (v5.1-rc1).
>
> I have applied the following patch for today. It could be applied as
> part of a merge of v5.1-rc1 into drm-misc.
>
> From: Stephen Rothwell <[email protected]>
> Date: Tue, 2 Apr 2019 10:45:32 +1100
> Subject: [PATCH] drm/lima: update for xa_alloc API change
>
> Signed-off-by: Stephen Rothwell <[email protected]>
> ---
> drivers/gpu/drm/lima/lima_ctx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/lima/lima_ctx.c b/drivers/gpu/drm/lima/lima_ctx.c
> index c8d12f7c6894..bafa00d74cc5 100644
> --- a/drivers/gpu/drm/lima/lima_ctx.c
> +++ b/drivers/gpu/drm/lima/lima_ctx.c
> @@ -23,7 +23,7 @@ int lima_ctx_create(struct lima_device *dev, struct lima_ctx_mgr *mgr, u32 *id)
> goto err_out0;
> }
>
> - err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> + err = xa_alloc(&mgr->handles, id, ctx, XA_LIMIT(*id, UINT_MAX), GFP_KERNEL);
> if (err < 0)
> goto err_out0;
>
> --
> 2.20.1
>
> --
> Cheers,
> Stephen Rothwell

2019-04-02 08:01:57

by Daniel Vetter

[permalink] [raw]
Subject: Re: linux-next: build failure after merge of the drm-misc tree

On Tue, Apr 02, 2019 at 01:55:03PM +0800, Qiang Yu wrote:
> Thanks, patch is:
> Reviewed-by: Qiang Yu <[email protected]>

Good time to get started with committing patches? In general it's kinda
confusing if the maintainer r-bs a patch, but doesn't say whether/when/how
it gets merged. Big chance the patch will get lost in limbo and fall
through cracks.
-Daniel

>
> Regards,
> Qiang
>
> On Tue, Apr 2, 2019 at 7:50 AM Stephen Rothwell <[email protected]> wrote:
> >
> > Hi all,
> >
> > After merging the drm-misc tree, today's linux-next build (x86_64
> > allmodconfig) failed like this:
> >
> > In file included from include/linux/kernel.h:7,
> > from include/asm-generic/bug.h:18,
> > from arch/x86/include/asm/bug.h:83,
> > from include/linux/bug.h:5,
> > from include/linux/mmdebug.h:5,
> > from include/linux/gfp.h:5,
> > from include/linux/slab.h:15,
> > from drivers/gpu/drm/lima/lima_ctx.c:4:
> > drivers/gpu/drm/lima/lima_ctx.c: In function 'lima_ctx_create':
> > include/linux/limits.h:13:18: warning: passing argument 3 of 'xa_alloc' makes pointer from integer without a cast [-Wint-conversion]
> > #define UINT_MAX (~0U)
> > ^~~~~
> > drivers/gpu/drm/lima/lima_ctx.c:26:36: note: in expansion of macro 'UINT_MAX'
> > err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> > ^~~~~~~~
> > In file included from include/linux/radix-tree.h:31,
> > from include/linux/idr.h:15,
> > from include/drm/drm_device.h:7,
> > from drivers/gpu/drm/lima/lima_device.h:7,
> > from drivers/gpu/drm/lima/lima_ctx.c:6:
> > include/linux/xarray.h:817:9: note: expected 'void *' but argument is of type 'unsigned int'
> > void *entry, struct xa_limit limit, gfp_t gfp)
> > ~~~~~~^~~~~
> > drivers/gpu/drm/lima/lima_ctx.c:26:46: error: incompatible type for argument 4 of 'xa_alloc'
> > err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> > ^~~
> > In file included from include/linux/radix-tree.h:31,
> > from include/linux/idr.h:15,
> > from include/drm/drm_device.h:7,
> > from drivers/gpu/drm/lima/lima_device.h:7,
> > from drivers/gpu/drm/lima/lima_ctx.c:6:
> > include/linux/xarray.h:817:32: note: expected 'struct xa_limit' but argument is of type 'struct lima_ctx *'
> > void *entry, struct xa_limit limit, gfp_t gfp)
> > ~~~~~~~~~~~~~~~~^~~~~
> >
> > Caused by commit
> >
> > a1d2a6339961 ("drm/lima: driver for ARM Mali4xx GPUs")
> >
> > interacting with commit
> >
> > a3e4d3f97ec8 ("XArray: Redesign xa_alloc API")
> >
> > from Linus' tree (v5.1-rc1).
> >
> > I have applied the following patch for today. It could be applied as
> > part of a merge of v5.1-rc1 into drm-misc.
> >
> > From: Stephen Rothwell <[email protected]>
> > Date: Tue, 2 Apr 2019 10:45:32 +1100
> > Subject: [PATCH] drm/lima: update for xa_alloc API change
> >
> > Signed-off-by: Stephen Rothwell <[email protected]>
> > ---
> > drivers/gpu/drm/lima/lima_ctx.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/lima/lima_ctx.c b/drivers/gpu/drm/lima/lima_ctx.c
> > index c8d12f7c6894..bafa00d74cc5 100644
> > --- a/drivers/gpu/drm/lima/lima_ctx.c
> > +++ b/drivers/gpu/drm/lima/lima_ctx.c
> > @@ -23,7 +23,7 @@ int lima_ctx_create(struct lima_device *dev, struct lima_ctx_mgr *mgr, u32 *id)
> > goto err_out0;
> > }
> >
> > - err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> > + err = xa_alloc(&mgr->handles, id, ctx, XA_LIMIT(*id, UINT_MAX), GFP_KERNEL);
> > if (err < 0)
> > goto err_out0;
> >
> > --
> > 2.20.1
> >
> > --
> > Cheers,
> > Stephen Rothwell

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

2019-04-02 09:09:18

by Daniel Vetter

[permalink] [raw]
Subject: Re: linux-next: build failure after merge of the drm-misc tree

On Tue, Apr 02, 2019 at 04:59:37PM +0800, Qiang Yu wrote:
> On Tue, Apr 2, 2019 at 3:57 PM Daniel Vetter <[email protected]> wrote:
> >
> > On Tue, Apr 02, 2019 at 01:55:03PM +0800, Qiang Yu wrote:
> > > Thanks, patch is:
> > > Reviewed-by: Qiang Yu <[email protected]>
> >
> > Good time to get started with committing patches? In general it's kinda
> > confusing if the maintainer r-bs a patch, but doesn't say whether/when/how
> > it gets merged. Big chance the patch will get lost in limbo and fall
> > through cracks.
>
> Thanks for the remind, this patch should only be applied to drm-misc-next
> branch when 5.1-rcx branch gets merged to drm-misc-next for the new
> xa_alloc API. So I expect the guy who do the 5.1-rcx merge should apply
> this patch. Who will do the merge?

Oh right, I was kinda not yet awake :-)

Yeah Dave/me and drm-misc maintainers will resolve this when drm-misc
lands in drm-next. Might then need a backmerge in drm-misc to roll
forward.
-Daniel

>
> Regards,
> Qiang
>
> >
> > >
> > > Regards,
> > > Qiang
> > >
> > > On Tue, Apr 2, 2019 at 7:50 AM Stephen Rothwell <[email protected]> wrote:
> > > >
> > > > Hi all,
> > > >
> > > > After merging the drm-misc tree, today's linux-next build (x86_64
> > > > allmodconfig) failed like this:
> > > >
> > > > In file included from include/linux/kernel.h:7,
> > > > from include/asm-generic/bug.h:18,
> > > > from arch/x86/include/asm/bug.h:83,
> > > > from include/linux/bug.h:5,
> > > > from include/linux/mmdebug.h:5,
> > > > from include/linux/gfp.h:5,
> > > > from include/linux/slab.h:15,
> > > > from drivers/gpu/drm/lima/lima_ctx.c:4:
> > > > drivers/gpu/drm/lima/lima_ctx.c: In function 'lima_ctx_create':
> > > > include/linux/limits.h:13:18: warning: passing argument 3 of 'xa_alloc' makes pointer from integer without a cast [-Wint-conversion]
> > > > #define UINT_MAX (~0U)
> > > > ^~~~~
> > > > drivers/gpu/drm/lima/lima_ctx.c:26:36: note: in expansion of macro 'UINT_MAX'
> > > > err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> > > > ^~~~~~~~
> > > > In file included from include/linux/radix-tree.h:31,
> > > > from include/linux/idr.h:15,
> > > > from include/drm/drm_device.h:7,
> > > > from drivers/gpu/drm/lima/lima_device.h:7,
> > > > from drivers/gpu/drm/lima/lima_ctx.c:6:
> > > > include/linux/xarray.h:817:9: note: expected 'void *' but argument is of type 'unsigned int'
> > > > void *entry, struct xa_limit limit, gfp_t gfp)
> > > > ~~~~~~^~~~~
> > > > drivers/gpu/drm/lima/lima_ctx.c:26:46: error: incompatible type for argument 4 of 'xa_alloc'
> > > > err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> > > > ^~~
> > > > In file included from include/linux/radix-tree.h:31,
> > > > from include/linux/idr.h:15,
> > > > from include/drm/drm_device.h:7,
> > > > from drivers/gpu/drm/lima/lima_device.h:7,
> > > > from drivers/gpu/drm/lima/lima_ctx.c:6:
> > > > include/linux/xarray.h:817:32: note: expected 'struct xa_limit' but argument is of type 'struct lima_ctx *'
> > > > void *entry, struct xa_limit limit, gfp_t gfp)
> > > > ~~~~~~~~~~~~~~~~^~~~~
> > > >
> > > > Caused by commit
> > > >
> > > > a1d2a6339961 ("drm/lima: driver for ARM Mali4xx GPUs")
> > > >
> > > > interacting with commit
> > > >
> > > > a3e4d3f97ec8 ("XArray: Redesign xa_alloc API")
> > > >
> > > > from Linus' tree (v5.1-rc1).
> > > >
> > > > I have applied the following patch for today. It could be applied as
> > > > part of a merge of v5.1-rc1 into drm-misc.
> > > >
> > > > From: Stephen Rothwell <[email protected]>
> > > > Date: Tue, 2 Apr 2019 10:45:32 +1100
> > > > Subject: [PATCH] drm/lima: update for xa_alloc API change
> > > >
> > > > Signed-off-by: Stephen Rothwell <[email protected]>
> > > > ---
> > > > drivers/gpu/drm/lima/lima_ctx.c | 2 +-
> > > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > > >
> > > > diff --git a/drivers/gpu/drm/lima/lima_ctx.c b/drivers/gpu/drm/lima/lima_ctx.c
> > > > index c8d12f7c6894..bafa00d74cc5 100644
> > > > --- a/drivers/gpu/drm/lima/lima_ctx.c
> > > > +++ b/drivers/gpu/drm/lima/lima_ctx.c
> > > > @@ -23,7 +23,7 @@ int lima_ctx_create(struct lima_device *dev, struct lima_ctx_mgr *mgr, u32 *id)
> > > > goto err_out0;
> > > > }
> > > >
> > > > - err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> > > > + err = xa_alloc(&mgr->handles, id, ctx, XA_LIMIT(*id, UINT_MAX), GFP_KERNEL);
> > > > if (err < 0)
> > > > goto err_out0;
> > > >
> > > > --
> > > > 2.20.1
> > > >
> > > > --
> > > > Cheers,
> > > > Stephen Rothwell
> >
> > --
> > Daniel Vetter
> > Software Engineer, Intel Corporation
> > http://blog.ffwll.ch

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

2019-04-02 09:32:12

by Qiang Yu

[permalink] [raw]
Subject: Re: linux-next: build failure after merge of the drm-misc tree

On Tue, Apr 2, 2019 at 3:57 PM Daniel Vetter <[email protected]> wrote:
>
> On Tue, Apr 02, 2019 at 01:55:03PM +0800, Qiang Yu wrote:
> > Thanks, patch is:
> > Reviewed-by: Qiang Yu <[email protected]>
>
> Good time to get started with committing patches? In general it's kinda
> confusing if the maintainer r-bs a patch, but doesn't say whether/when/how
> it gets merged. Big chance the patch will get lost in limbo and fall
> through cracks.

Thanks for the remind, this patch should only be applied to drm-misc-next
branch when 5.1-rcx branch gets merged to drm-misc-next for the new
xa_alloc API. So I expect the guy who do the 5.1-rcx merge should apply
this patch. Who will do the merge?

Regards,
Qiang

>
> >
> > Regards,
> > Qiang
> >
> > On Tue, Apr 2, 2019 at 7:50 AM Stephen Rothwell <[email protected]> wrote:
> > >
> > > Hi all,
> > >
> > > After merging the drm-misc tree, today's linux-next build (x86_64
> > > allmodconfig) failed like this:
> > >
> > > In file included from include/linux/kernel.h:7,
> > > from include/asm-generic/bug.h:18,
> > > from arch/x86/include/asm/bug.h:83,
> > > from include/linux/bug.h:5,
> > > from include/linux/mmdebug.h:5,
> > > from include/linux/gfp.h:5,
> > > from include/linux/slab.h:15,
> > > from drivers/gpu/drm/lima/lima_ctx.c:4:
> > > drivers/gpu/drm/lima/lima_ctx.c: In function 'lima_ctx_create':
> > > include/linux/limits.h:13:18: warning: passing argument 3 of 'xa_alloc' makes pointer from integer without a cast [-Wint-conversion]
> > > #define UINT_MAX (~0U)
> > > ^~~~~
> > > drivers/gpu/drm/lima/lima_ctx.c:26:36: note: in expansion of macro 'UINT_MAX'
> > > err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> > > ^~~~~~~~
> > > In file included from include/linux/radix-tree.h:31,
> > > from include/linux/idr.h:15,
> > > from include/drm/drm_device.h:7,
> > > from drivers/gpu/drm/lima/lima_device.h:7,
> > > from drivers/gpu/drm/lima/lima_ctx.c:6:
> > > include/linux/xarray.h:817:9: note: expected 'void *' but argument is of type 'unsigned int'
> > > void *entry, struct xa_limit limit, gfp_t gfp)
> > > ~~~~~~^~~~~
> > > drivers/gpu/drm/lima/lima_ctx.c:26:46: error: incompatible type for argument 4 of 'xa_alloc'
> > > err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> > > ^~~
> > > In file included from include/linux/radix-tree.h:31,
> > > from include/linux/idr.h:15,
> > > from include/drm/drm_device.h:7,
> > > from drivers/gpu/drm/lima/lima_device.h:7,
> > > from drivers/gpu/drm/lima/lima_ctx.c:6:
> > > include/linux/xarray.h:817:32: note: expected 'struct xa_limit' but argument is of type 'struct lima_ctx *'
> > > void *entry, struct xa_limit limit, gfp_t gfp)
> > > ~~~~~~~~~~~~~~~~^~~~~
> > >
> > > Caused by commit
> > >
> > > a1d2a6339961 ("drm/lima: driver for ARM Mali4xx GPUs")
> > >
> > > interacting with commit
> > >
> > > a3e4d3f97ec8 ("XArray: Redesign xa_alloc API")
> > >
> > > from Linus' tree (v5.1-rc1).
> > >
> > > I have applied the following patch for today. It could be applied as
> > > part of a merge of v5.1-rc1 into drm-misc.
> > >
> > > From: Stephen Rothwell <[email protected]>
> > > Date: Tue, 2 Apr 2019 10:45:32 +1100
> > > Subject: [PATCH] drm/lima: update for xa_alloc API change
> > >
> > > Signed-off-by: Stephen Rothwell <[email protected]>
> > > ---
> > > drivers/gpu/drm/lima/lima_ctx.c | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/gpu/drm/lima/lima_ctx.c b/drivers/gpu/drm/lima/lima_ctx.c
> > > index c8d12f7c6894..bafa00d74cc5 100644
> > > --- a/drivers/gpu/drm/lima/lima_ctx.c
> > > +++ b/drivers/gpu/drm/lima/lima_ctx.c
> > > @@ -23,7 +23,7 @@ int lima_ctx_create(struct lima_device *dev, struct lima_ctx_mgr *mgr, u32 *id)
> > > goto err_out0;
> > > }
> > >
> > > - err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> > > + err = xa_alloc(&mgr->handles, id, ctx, XA_LIMIT(*id, UINT_MAX), GFP_KERNEL);
> > > if (err < 0)
> > > goto err_out0;
> > >
> > > --
> > > 2.20.1
> > >
> > > --
> > > Cheers,
> > > Stephen Rothwell
>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch

2019-04-02 11:53:29

by Matthew Wilcox

[permalink] [raw]
Subject: Re: linux-next: build failure after merge of the drm-misc tree

On Tue, Apr 02, 2019 at 10:50:06AM +1100, Stephen Rothwell wrote:
> +++ b/drivers/gpu/drm/lima/lima_ctx.c
> @@ -23,7 +23,7 @@ int lima_ctx_create(struct lima_device *dev, struct lima_ctx_mgr *mgr, u32 *id)
> goto err_out0;
> }
>
> - err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> + err = xa_alloc(&mgr->handles, id, ctx, XA_LIMIT(*id, UINT_MAX), GFP_KERNEL);
> if (err < 0)
> goto err_out0;

I agree that this is an exact translation of what the code was doing,
but I don't think it's what the author intended the code to do.
They almost certainly meant:

err = xa_alloc(&mgr->handles, id, ctx, xa_limit_32b, GFP_KERNEL);

I'm basing this on:

+struct drm_lima_ctx_create {
+ __u32 id; /* out, context handle */
+ __u32 _pad; /* pad, must be zero */
+};

(and this confusion is exactly why I changed the API ...)

2019-04-02 12:58:30

by Matthew Wilcox

[permalink] [raw]
Subject: Re: linux-next: build failure after merge of the drm-misc tree

On Tue, Apr 02, 2019 at 01:55:03PM +0800, Qiang Yu wrote:
> Thanks, patch is:
> Reviewed-by: Qiang Yu <[email protected]>

This looks like a fairly naive conversion from the old IDR API to the
XArray API. You should be able to remove mgr->lock entirely, relying on
the xa_lock for synchronising free and get. If you think it's worth it,
you could even use kfree_rcu() to free the ctx and kref_get_unless_zero()
and then your get path would be lock-free.

2019-04-02 13:48:08

by Qiang Yu

[permalink] [raw]
Subject: [PATCH] drm/lima: adopt xa_alloc API change

Cc: Stephen Rothwell <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Daniel Vetter <[email protected]>
Signed-off-by: Qiang Yu <[email protected]>
---
drivers/gpu/drm/lima/lima_ctx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/lima/lima_ctx.c b/drivers/gpu/drm/lima/lima_ctx.c
index c8d12f7c6894..22fff6caa961 100644
--- a/drivers/gpu/drm/lima/lima_ctx.c
+++ b/drivers/gpu/drm/lima/lima_ctx.c
@@ -23,7 +23,7 @@ int lima_ctx_create(struct lima_device *dev, struct lima_ctx_mgr *mgr, u32 *id)
goto err_out0;
}

- err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
+ err = xa_alloc(&mgr->handles, id, ctx, xa_limit_32b, GFP_KERNEL);
if (err < 0)
goto err_out0;

--
2.17.1

2019-04-02 13:57:44

by Qiang Yu

[permalink] [raw]
Subject: Re: linux-next: build failure after merge of the drm-misc tree

On Tue, Apr 2, 2019 at 7:26 PM Matthew Wilcox <[email protected]> wrote:
>
> On Tue, Apr 02, 2019 at 01:55:03PM +0800, Qiang Yu wrote:
> > Thanks, patch is:
> > Reviewed-by: Qiang Yu <[email protected]>
>
> This looks like a fairly naive conversion from the old IDR API to the
> XArray API. You should be able to remove mgr->lock entirely, relying on
> the xa_lock for synchronising free and get.

I'm afraid the a little complex free path may involve some might sleep
functions so use a mutex lock instead of spinlock.

> If you think it's worth it,
> you could even use kfree_rcu() to free the ctx and kref_get_unless_zero()
> and then your get path would be lock-free.

I can take a look this way, thanks.

2019-04-02 14:12:03

by Matthew Wilcox

[permalink] [raw]
Subject: Re: linux-next: build failure after merge of the drm-misc tree

On Tue, Apr 02, 2019 at 09:56:08PM +0800, Qiang Yu wrote:
> On Tue, Apr 2, 2019 at 7:26 PM Matthew Wilcox <[email protected]> wrote:
> >
> > On Tue, Apr 02, 2019 at 01:55:03PM +0800, Qiang Yu wrote:
> > > Thanks, patch is:
> > > Reviewed-by: Qiang Yu <[email protected]>
> >
> > This looks like a fairly naive conversion from the old IDR API to the
> > XArray API. You should be able to remove mgr->lock entirely, relying on
> > the xa_lock for synchronising free and get.
>
> I'm afraid the a little complex free path may involve some might sleep
> functions so use a mutex lock instead of spinlock.

Ah, good call ...

+ mutex_lock(&mgr->lock);
+ ctx = xa_erase(&mgr->handles, id);
+ if (ctx)
+ kref_put(&ctx->refcnt, lima_ctx_do_release);
+ else
+ ret = -EINVAL;
+ mutex_unlock(&mgr->lock);

+static void lima_ctx_do_release(struct kref *ref)
+{
+ struct lima_ctx *ctx = container_of(ref, struct lima_ctx, refcnt);
+ int i;
+
+ for (i = 0; i < lima_pipe_num; i++)
+ lima_sched_context_fini(ctx->dev->pipe + i, ctx->context + i);
+ kfree(ctx);
+}

+void lima_sched_context_fini(struct lima_sched_pipe *pipe,
+ struct lima_sched_context *context)
+{
+ drm_sched_entity_fini(&context->base);
+}

and drm_sched_entity_fini() can call kthread_park(), which does sleep.

> > If you think it's worth it,
> > you could even use kfree_rcu() to free the ctx and kref_get_unless_zero()
> > and then your get path would be lock-free.
>
> I can take a look this way, thanks.

I think that's the only way you can get rid of the mutex, given the
sleeping functions called in the free path.

2019-04-02 14:35:23

by Qiang Yu

[permalink] [raw]
Subject: Re: linux-next: build failure after merge of the drm-misc tree

On Tue, Apr 2, 2019 at 7:21 PM Matthew Wilcox <[email protected]> wrote:
>
> On Tue, Apr 02, 2019 at 10:50:06AM +1100, Stephen Rothwell wrote:
> > +++ b/drivers/gpu/drm/lima/lima_ctx.c
> > @@ -23,7 +23,7 @@ int lima_ctx_create(struct lima_device *dev, struct lima_ctx_mgr *mgr, u32 *id)
> > goto err_out0;
> > }
> >
> > - err = xa_alloc(&mgr->handles, id, UINT_MAX, ctx, GFP_KERNEL);
> > + err = xa_alloc(&mgr->handles, id, ctx, XA_LIMIT(*id, UINT_MAX), GFP_KERNEL);
> > if (err < 0)
> > goto err_out0;
>
> I agree that this is an exact translation of what the code was doing,
> but I don't think it's what the author intended the code to do.
> They almost certainly meant:
>
> err = xa_alloc(&mgr->handles, id, ctx, xa_limit_32b, GFP_KERNEL);
>
> I'm basing this on:
>
> +struct drm_lima_ctx_create {
> + __u32 id; /* out, context handle */
> + __u32 _pad; /* pad, must be zero */
> +};
>
> (and this confusion is exactly why I changed the API ...)

Right, I plan to send out a patch like yours after drm-misc-next merge
5.1 changes, as this is a build fix patch and already applied to somewhere.
I can send out another patch now if merge guys could use the new one
directly.