2017-04-03 11:11:41

by Julien Beraud

Subject: [PATCH 1/1] nios2: implement flush_dcache_mmap_lock/unlock

Use spin_lock/unlock_irq instead of doing nothing. This fixes corruptions
of the vma_interval_tree causing the kernel to be stuck in an
infinite loop in vma_interval_tree_foreach.

Signed-off-by: Julien Beraud <[email protected]>
---
arch/nios2/include/asm/cacheflush.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/nios2/include/asm/cacheflush.h b/arch/nios2/include/asm/cacheflush.h
index 52abba973dc2..55e383c173f7 100644
--- a/arch/nios2/include/asm/cacheflush.h
+++ b/arch/nios2/include/asm/cacheflush.h
@@ -46,7 +46,9 @@ extern void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
extern void flush_dcache_range(unsigned long start, unsigned long end);
extern void invalidate_dcache_range(unsigned long start, unsigned long end);

-#define flush_dcache_mmap_lock(mapping) do { } while (0)
-#define flush_dcache_mmap_unlock(mapping) do { } while (0)
+#define flush_dcache_mmap_lock(mapping) \
+ spin_lock_irq(&(mapping)->tree_lock)
+#define flush_dcache_mmap_unlock(mapping) \
+ spin_unlock_irq(&(mapping)->tree_lock)

#endif /* _ASM_NIOS2_CACHEFLUSH_H */
--
2.11.0

2017-04-11 07:50:13

by Tan, Ley Foon

Subject: Re: [PATCH 1/1] nios2: implement flush_dcache_mmap_lock/unlock

On Mon, 2017-04-03 at 13:11 +0200, Julien Beraud wrote:
> Use spin_lock/unlock_irq instead of doing nothing. This fixes
> corruptions
> of the vma_interval_tree causing the kernel to be stuck in an
> infinite loop in vma_interval_tree_foreach.
>
> Signed-off-by: Julien Beraud <[email protected]>
> ---
>  arch/nios2/include/asm/cacheflush.h | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/nios2/include/asm/cacheflush.h
> b/arch/nios2/include/asm/cacheflush.h
> index 52abba973dc2..55e383c173f7 100644
> --- a/arch/nios2/include/asm/cacheflush.h
> +++ b/arch/nios2/include/asm/cacheflush.h
> @@ -46,7 +46,9 @@ extern void copy_from_user_page(struct
> vm_area_struct *vma, struct page *page,
>  extern void flush_dcache_range(unsigned long start, unsigned long
> end);
>  extern void invalidate_dcache_range(unsigned long start, unsigned
> long end);
>
> -#define flush_dcache_mmap_lock(mapping)                do { } while
> (0)
> -#define flush_dcache_mmap_unlock(mapping)      do { } while (0)
> +#define flush_dcache_mmap_lock(mapping) \
> +       spin_lock_irq(&(mapping)->tree_lock)
> +#define flush_dcache_mmap_unlock(mapping) \
> +       spin_unlock_irq(&(mapping)->tree_lock)
>
>  #endif /* _ASM_NIOS2_CACHEFLUSH_H */
> --
> 2.11.0
>
Acked-by: Ley Foon Tan <[email protected]>

Regards
Ley Foon