ARM: nommu: avoid mapping vectors page when !CONFIG_MMU
PATCH 1/1 ARM: nommu: avoid mapping vectors page when !CONFIG_MMU
When running without an MMU, we do not need to install a mapping for the vectors page. Attempting to do so causes a compile-time error because install_special_mapping is not defined.
This patch adds compile-time guards to the vector mapping functions so that we can build nommu configurations once more.
--- arch/arm/kernel/process.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)
arch/arm/kernel/process.c +2 -0
@@ -483,6 +483,7 @@ unsigned long arch_randomize_brk(struct mm_struct *mm)return randomize_range (mm->brk, range_end,0 ) ? : mm->brk; } +#ifdef CONFIG_MMU /* * The vectors page is always readable from user space for the * atomic helpers and the signal restart code. Let's declare a mapping
@@ -503,3 +504,4 @@ const char *arch_vma_name(struct vm_area_struct *vma) {return (vma->vm_start ==0xffff0000 ) ?"[vectors]" :NULL ; } +#endif
Signature · 1 line
1.7.0.4
PATCH 1/1 ARM: nommu: avoid mapping vectors page when !CONFIG_MMU
Quoted 6 lines · Will Deacon
When running without an MMU, we do not need to install a mapping for the vectors page. Attempting to do so causes a compile-time error because
install_special_mappingis not defined.This patch adds compile-time guards to the vector mapping functions so that we can build nommu configurations once more.
I had a similar patch a few days ago doing the same thing... when Greg's acked it, please submit to the patch system, thanks.
PATCH 1/1 ARM: nommu: avoid mapping vectors page when !CONFIG_MMU
In reply to Will DeaconHi Will,
Quoted 9 lines · Will Deacon
When running without an MMU, we do not need to install a mapping for the vectors page. Attempting to do so causes a compile-time error because
install_special_mappingis not defined.This patch adds compile-time guards to the vector mapping functions so that we can build nommu configurations once more.
Cc Greg Ungerer<[email protected]>Signed-off-by Will Deacon<[email protected]>
I hit this a couple of days ago too, looks good.
Regards
Greg
Quoted 20 lines
arch/arm/kernel/process.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)arch/arm/kernel/process.c +2
-0@@ -483,6 +483,7 @@ unsigned long arch_randomize_brk(struct mm_struct *mm)return randomize_range (mm->brk, range_end,0 ) ? : mm->brk; } +#ifdef CONFIG_MMU /* * The vectors page is always readable from user space for the * atomic helpers and the signal restart code. Let's declare a mapping @@ -503,3 +504,4 @@ const char *arch_vma_name(struct vm_area_struct *vma) {return (vma->vm_start ==0xffff0000 ) ?"[vectors]" :NULL ; } +#endif
Signature · 5 lines
------------------------------------------------------------------------ Greg Ungerer -- Principal Engineer EMAIL: gerg at snapgear.com SnapGear Group, McAfee PHONE: +61 7 3435 2888 8 Gardner Close, FAX: +61 7 3891 3630 Milton, QLD, 4064, Australia WEB: http://www.SnapGear.com
PATCH 1/1 ARM: nommu: avoid mapping vectors page when !CONFIG_MMU
Hi Greg,
Quoted 7 lines
Quoted 7 lines
When running without an MMU, we do not need to install a mapping for the vectors page. Attempting to do so causes a compile-time error because
install_special_mappingis not defined.This patch adds compile-time guards to the vector mapping functions so that we can build nommu configurations once more.
Quoted 6 lines
Quoted 2 lines
Cc Greg Ungerer<[email protected]>Signed-off-by Will Deacon<[email protected]>I hit this a couple of days ago too, looks good.
Acked-by Greg Ungerer <[email protected]>
Thanks. Submitted to Russell as 6619/1.
Will