[PATCH] powerpc/mm: remove warning about ‘type’ being set

‘type’ is only used when CONFIG_DEBUG_HIGHMEM is set. So add a possibly
unused tag to variable. Remove warning treated as error with W=1:

  arch/powerpc/mm/highmem.c:59:6: error: variable ‘type’ set but not used [-Werror=unused-but-set-variable]

Signed-off-by: Mathieu Malaterre <redacted>
---
 arch/powerpc/mm/highmem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/highmem.c b/arch/powerpc/mm/highmem.c
index 668e87d03f9e..82a0e37557a5 100644
--- a/arch/powerpc/mm/highmem.c
+++ b/arch/powerpc/mm/highmem.c

@@ -56,7 +56,7 @@ EXPORT_SYMBOL(kmap_atomic_prot);
 void __kunmap_atomic(void *kvaddr)
 {
 	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-	int type;
+	int type __maybe_unused;
 
 	if (vaddr < __fix_to_virt(FIX_KMAP_END)) {
 		pagefault_enable();

-- 
2.11.0

Le 22/06/2018 à 21:27, Mathieu Malaterre a écrit :

‘type’ is only used when CONFIG_DEBUG_HIGHMEM is set. So add a possibly
unused tag to variable. Remove warning treated as error with W=1:

   arch/powerpc/mm/highmem.c:59:6: error: variable ‘type’ set but not used [-Werror=unused-but-set-variable]

Is type neeeded at all when CONFIG_DEBUG_HIGHMEM is not set ?

The call 	type = kmap_atomic_idx();          seems useless when 
CONFIG_DEBUG_HIGHMEM isn't set. Couldn't we just most type definition 
and setting inside the CONFIG_DEBUG_HIGHMEM {} below ?

Alternatively, maybe you could replace the #ifdef CONFIG_DEBUG_HIGHMEM 
by an    if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM)) ?

Christophe

---
L'absence de virus dans ce courrier électronique a été vérifiée par le logiciel antivirus Avast.
https://www.avast.com/antivirus

On Sat, Jun 23, 2018 at 7:12 PM christophe leroy
[off-list ref] wrote:

Le 22/06/2018 =C3=A0 21:27, Mathieu Malaterre a =C3=A9crit :

quoted

=E2=80=98type=E2=80=99 is only used when CONFIG_DEBUG_HIGHMEM is set. S=

o add a possibly

quoted

unused tag to variable. Remove warning treated as error with W=3D1:

   arch/powerpc/mm/highmem.c:59:6: error: variable =E2=80=98type=E2=80=

=99 set but not used [-Werror=3Dunused-but-set-variable]

Is type neeeded at all when CONFIG_DEBUG_HIGHMEM is not set ?

The call        type =3D kmap_atomic_idx();          seems useless when
CONFIG_DEBUG_HIGHMEM isn't set. Couldn't we just most type definition
and setting inside the CONFIG_DEBUG_HIGHMEM {} below ?

Alternatively, maybe you could replace the #ifdef CONFIG_DEBUG_HIGHMEM
by an    if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM)) ?

I am not familiar with this code. But starring at other arch
implementations (eg. `arch/x86/mm/highmem_32.c`), it feels like
powerpc is skipping `pte_clear(&init_mm, vaddr, kmap_pte-idx);` unless
`CONFIG_DEBUG_HIGHMEM=3Dy`. Could someone please confirm this is the
correct behavior ?

Or else I can rewrite the code a bit like `arch/arm/mm/highmem.c`
which skips `set_fixmap_pte(idx, __pte(0));` unless
`CONFIG_DEBUG_HIGHMEM=3Dy`.

Christophe

quoted

Signed-off-by: Mathieu Malaterre <redacted>
---
  arch/powerpc/mm/highmem.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/highmem.c b/arch/powerpc/mm/highmem.c
index 668e87d03f9e..82a0e37557a5 100644
--- a/arch/powerpc/mm/highmem.c
+++ b/arch/powerpc/mm/highmem.c

@@ -56,7 +56,7 @@ EXPORT_SYMBOL(kmap_atomic_prot);
  void __kunmap_atomic(void *kvaddr)
  {
      unsigned long vaddr =3D (unsigned long) kvaddr & PAGE_MASK;
-     int type;
+     int type __maybe_unused;

      if (vaddr < __fix_to_virt(FIX_KMAP_END)) {
              pagefault_enable();

---
L'absence de virus dans ce courrier =C3=A9lectronique a =C3=A9t=C3=A9 v=

=C3=A9rifi=C3=A9e par le logiciel antivirus Avast.

https://www.avast.com/antivirus

On Fri, 2018-06-22 at 19:27:47 UTC, Mathieu Malaterre wrote:

���type��� is only used when CONFIG_DEBUG_HIGHMEM is set. So add a possibly
unused tag to variable. Remove warning treated as error with W=1:

  arch/powerpc/mm/highmem.c:59:6: error: variable ���type��� set but not used [-Werror=unused-but-set-variable]

Signed-off-by: Mathieu Malaterre <redacted>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/fce278af81daf8599f9e94883cbe43

cheers