diff mbox

[2/2] efi: Fix warning of int-to-pointer-cast on x86 32-bit builds

Message ID 1445593697-1342-2-git-send-email-ard.biesheuvel@linaro.org
State New
Headers show

Commit Message

Ard Biesheuvel Oct. 23, 2015, 9:48 a.m. UTC
From: Taku Izumi <izumi.taku@jp.fujitsu.com>

Commit 0f96a99dab36 ("efi: Add "efi_fake_mem" boot option")
introduces the following warning message:

  drivers/firmware/efi/fake_mem.c:186:20: warning: cast to pointer
  from integer of different size [-Wint-to-pointer-cast]

new_memmap_phy was defined as a u64 value and cast to void*, causing
a int-to-pointer-cast warning on x86 32-bit builds.
However, since the void* type is inappropriate for a physical
address, the definition of struct efi_memory_map::phys_map has been
changed to phys_addr_t in the previous patch, and so the cast can be
dropped entirely.

This patch also changes the type of the "new_memmap_phy" variable
from "u64" to "phys_addr_t" to align with the types of
memblock_alloc() and struct efi_memory_map::phys_map.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
[ard.biesheuvel: removed void* cast, updated commit log]
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 drivers/firmware/efi/fake_mem.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Ingo Molnar Oct. 23, 2015, 10:27 a.m. UTC | #1
* Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:

> From: Taku Izumi <izumi.taku@jp.fujitsu.com>
> 
> Commit 0f96a99dab36 ("efi: Add "efi_fake_mem" boot option")
> introduces the following warning message:
> 
>   drivers/firmware/efi/fake_mem.c:186:20: warning: cast to pointer
>   from integer of different size [-Wint-to-pointer-cast]
> 
> new_memmap_phy was defined as a u64 value and cast to void*, causing
> a int-to-pointer-cast warning on x86 32-bit builds.
> However, since the void* type is inappropriate for a physical
> address, the definition of struct efi_memory_map::phys_map has been
> changed to phys_addr_t in the previous patch, and so the cast can be
> dropped entirely.
> 
> This patch also changes the type of the "new_memmap_phy" variable
> from "u64" to "phys_addr_t" to align with the types of
> memblock_alloc() and struct efi_memory_map::phys_map.
> 
> Reported-by: Ingo Molnar <mingo@kernel.org>
> Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
> [ard.biesheuvel: removed void* cast, updated commit log]
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
>  drivers/firmware/efi/fake_mem.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/firmware/efi/fake_mem.c b/drivers/firmware/efi/fake_mem.c
> index 32bcb14df2c8..ed3a854950cc 100644
> --- a/drivers/firmware/efi/fake_mem.c
> +++ b/drivers/firmware/efi/fake_mem.c
> @@ -59,7 +59,7 @@ void __init efi_fake_memmap(void)
>  	u64 start, end, m_start, m_end, m_attr;
>  	int new_nr_map = memmap.nr_map;
>  	efi_memory_desc_t *md;
> -	u64 new_memmap_phy;
> +	phys_addr_t new_memmap_phy;
>  	void *new_memmap;
>  	void *old, *new;
>  	int i;
> @@ -183,7 +183,7 @@ void __init efi_fake_memmap(void)
>  	/* swap into new EFI memmap */
>  	efi_unmap_memmap();
>  	memmap.map = new_memmap;
> -	memmap.phys_map = (void *)new_memmap_phy;
> +	memmap.phys_map = new_memmap_phy;
>  	memmap.nr_map = new_nr_map;
>  	memmap.map_end = memmap.map + memmap.nr_map * memmap.desc_size;

Please guys, think for a change!

How is this supposed to work with:

   include/linux/efi.h:    void *phys_map;

?

Thanks,

	Ingo

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Ingo Molnar Oct. 23, 2015, 10:30 a.m. UTC | #2
* Ingo Molnar <mingo@kernel.org> wrote:

> 
> * Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:
> 
> > From: Taku Izumi <izumi.taku@jp.fujitsu.com>
> > 
> > Commit 0f96a99dab36 ("efi: Add "efi_fake_mem" boot option")
> > introduces the following warning message:
> > 
> >   drivers/firmware/efi/fake_mem.c:186:20: warning: cast to pointer
> >   from integer of different size [-Wint-to-pointer-cast]
> > 
> > new_memmap_phy was defined as a u64 value and cast to void*, causing
> > a int-to-pointer-cast warning on x86 32-bit builds.
> > However, since the void* type is inappropriate for a physical
> > address, the definition of struct efi_memory_map::phys_map has been
> > changed to phys_addr_t in the previous patch, and so the cast can be
> > dropped entirely.
> > 
> > This patch also changes the type of the "new_memmap_phy" variable
> > from "u64" to "phys_addr_t" to align with the types of
> > memblock_alloc() and struct efi_memory_map::phys_map.
> > 
> > Reported-by: Ingo Molnar <mingo@kernel.org>
> > Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
> > [ard.biesheuvel: removed void* cast, updated commit log]
> > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> > ---
> >  drivers/firmware/efi/fake_mem.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/firmware/efi/fake_mem.c b/drivers/firmware/efi/fake_mem.c
> > index 32bcb14df2c8..ed3a854950cc 100644
> > --- a/drivers/firmware/efi/fake_mem.c
> > +++ b/drivers/firmware/efi/fake_mem.c
> > @@ -59,7 +59,7 @@ void __init efi_fake_memmap(void)
> >  	u64 start, end, m_start, m_end, m_attr;
> >  	int new_nr_map = memmap.nr_map;
> >  	efi_memory_desc_t *md;
> > -	u64 new_memmap_phy;
> > +	phys_addr_t new_memmap_phy;
> >  	void *new_memmap;
> >  	void *old, *new;
> >  	int i;
> > @@ -183,7 +183,7 @@ void __init efi_fake_memmap(void)
> >  	/* swap into new EFI memmap */
> >  	efi_unmap_memmap();
> >  	memmap.map = new_memmap;
> > -	memmap.phys_map = (void *)new_memmap_phy;
> > +	memmap.phys_map = new_memmap_phy;
> >  	memmap.nr_map = new_nr_map;
> >  	memmap.map_end = memmap.map + memmap.nr_map * memmap.desc_size;
> 
> Please guys, think for a change!
> 
> How is this supposed to work with:
> 
>    include/linux/efi.h:    void *phys_map;
> 
> ?

Ah, I take that back, now I see your patch 1/2 that changes it to phys_addr_t.

That's the right solution, and it also cleans up the code:

  Reviewed-by: Ingo Molnar <mingo@kernel.org>

Thanks,

	Ingo
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Ingo Molnar Oct. 23, 2015, 10:33 a.m. UTC | #3
* Ingo Molnar <mingo@kernel.org> wrote:

> 
> * Ingo Molnar <mingo@kernel.org> wrote:
> 
> > 
> > * Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:
> > 
> > > From: Taku Izumi <izumi.taku@jp.fujitsu.com>
> > > 
> > > Commit 0f96a99dab36 ("efi: Add "efi_fake_mem" boot option")
> > > introduces the following warning message:
> > > 
> > >   drivers/firmware/efi/fake_mem.c:186:20: warning: cast to pointer
> > >   from integer of different size [-Wint-to-pointer-cast]
> > > 
> > > new_memmap_phy was defined as a u64 value and cast to void*, causing
> > > a int-to-pointer-cast warning on x86 32-bit builds.
> > > However, since the void* type is inappropriate for a physical
> > > address, the definition of struct efi_memory_map::phys_map has been
> > > changed to phys_addr_t in the previous patch, and so the cast can be
> > > dropped entirely.
> > > 
> > > This patch also changes the type of the "new_memmap_phy" variable
> > > from "u64" to "phys_addr_t" to align with the types of
> > > memblock_alloc() and struct efi_memory_map::phys_map.
> > > 
> > > Reported-by: Ingo Molnar <mingo@kernel.org>
> > > Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
> > > [ard.biesheuvel: removed void* cast, updated commit log]
> > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> > > ---
> > >  drivers/firmware/efi/fake_mem.c | 4 ++--
> > >  1 file changed, 2 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/drivers/firmware/efi/fake_mem.c b/drivers/firmware/efi/fake_mem.c
> > > index 32bcb14df2c8..ed3a854950cc 100644
> > > --- a/drivers/firmware/efi/fake_mem.c
> > > +++ b/drivers/firmware/efi/fake_mem.c
> > > @@ -59,7 +59,7 @@ void __init efi_fake_memmap(void)
> > >  	u64 start, end, m_start, m_end, m_attr;
> > >  	int new_nr_map = memmap.nr_map;
> > >  	efi_memory_desc_t *md;
> > > -	u64 new_memmap_phy;
> > > +	phys_addr_t new_memmap_phy;
> > >  	void *new_memmap;
> > >  	void *old, *new;
> > >  	int i;
> > > @@ -183,7 +183,7 @@ void __init efi_fake_memmap(void)
> > >  	/* swap into new EFI memmap */
> > >  	efi_unmap_memmap();
> > >  	memmap.map = new_memmap;
> > > -	memmap.phys_map = (void *)new_memmap_phy;
> > > +	memmap.phys_map = new_memmap_phy;
> > >  	memmap.nr_map = new_nr_map;
> > >  	memmap.map_end = memmap.map + memmap.nr_map * memmap.desc_size;
> > 
> > Please guys, think for a change!
> > 
> > How is this supposed to work with:
> > 
> >    include/linux/efi.h:    void *phys_map;
> > 
> > ?
> 
> Ah, I take that back, now I see your patch 1/2 that changes it to phys_addr_t.
> 
> That's the right solution, and it also cleans up the code:
> 
>   Reviewed-by: Ingo Molnar <mingo@kernel.org>

Matt, do you want to take these fixes, or should I apply them directly?

Thanks,

	Ingo
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diff mbox

Patch

diff --git a/drivers/firmware/efi/fake_mem.c b/drivers/firmware/efi/fake_mem.c
index 32bcb14df2c8..ed3a854950cc 100644
--- a/drivers/firmware/efi/fake_mem.c
+++ b/drivers/firmware/efi/fake_mem.c
@@ -59,7 +59,7 @@  void __init efi_fake_memmap(void)
 	u64 start, end, m_start, m_end, m_attr;
 	int new_nr_map = memmap.nr_map;
 	efi_memory_desc_t *md;
-	u64 new_memmap_phy;
+	phys_addr_t new_memmap_phy;
 	void *new_memmap;
 	void *old, *new;
 	int i;
@@ -183,7 +183,7 @@  void __init efi_fake_memmap(void)
 	/* swap into new EFI memmap */
 	efi_unmap_memmap();
 	memmap.map = new_memmap;
-	memmap.phys_map = (void *)new_memmap_phy;
+	memmap.phys_map = new_memmap_phy;
 	memmap.nr_map = new_nr_map;
 	memmap.map_end = memmap.map + memmap.nr_map * memmap.desc_size;
 	set_bit(EFI_MEMMAP, &efi.flags);