[PATCH 3/3] powerpc/mm: Use VMALLOC_START to validate addr

[Christophe Leroy]

Le 23/06/2022 à 14:29, Aneesh Kumar K.V a écrit :
> Instead of high_memory use VMALLOC_START to validate that the address is
> not in the vmalloc range.

What's the reason for using VMALLOC_START instead ?
The gap between high_memory and VMALLOC_START should not be seen as 
valid memory either, should it ?

If the problem is book3s/64, commit ffa0b64e3be5 ("powerpc: Fix 
virt_addr_valid() for 64-bit Book3E & 32-bit") says that those 
additional tests are superfluous for boo3s/64. Maybe it's time to drop 
unnecessary tests for book3s/64 ?

> 
> Cc: Kefeng Wang <wangkefeng.wang at huawei.com>
> Cc: Christophe Leroy <christophe.leroy at csgroup.eu>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.ibm.com>
> ---
>   arch/powerpc/include/asm/page.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
> index e5f75c70eda8..256cad69e42e 100644
> --- a/arch/powerpc/include/asm/page.h
> +++ b/arch/powerpc/include/asm/page.h
> @@ -134,7 +134,7 @@ static inline bool pfn_valid(unsigned long pfn)
>   
>   #define virt_addr_valid(vaddr)	({					\
>   	unsigned long _addr = (unsigned long)vaddr;			\
> -	_addr >= PAGE_OFFSET && _addr < (unsigned long)high_memory &&	\
> +	_addr >= PAGE_OFFSET && _addr < (unsigned long)VMALLOC_START &&	\
>   	pfn_valid(virt_to_pfn(_addr));					\
>   })
>