Subject: Re: [PATCH v6 4/4] powerpc: Book3S 64-bit "heavyweight" KASAN support

From: Daniel Axtens <[email-masked]>
Date: Wed, 12 Feb 2020 21:12:12 +1100

Christophe Leroy <[email-masked]> writes:

> Le 12/02/2020 à 06:47, Daniel Axtens a écrit :
>> diff --git a/arch/powerpc/include/asm/kasan.h b/arch/powerpc/include/asm/kasan.h
>> index fbff9ff9032e..2911fdd3a6a0 100644
>> --- a/arch/powerpc/include/asm/kasan.h
>> +++ b/arch/powerpc/include/asm/kasan.h
>> @@ -2,6 +2,8 @@
>>   #ifndef __ASM_KASAN_H
>>   #define __ASM_KASAN_H
>>   
>> +#include <asm/page.h>
>> +
>>   #ifdef CONFIG_KASAN
>>   #define _GLOBAL_KASAN(fn)	_GLOBAL(__##fn)
>>   #define _GLOBAL_TOC_KASAN(fn)	_GLOBAL_TOC(__##fn)
>> @@ -14,29 +16,41 @@
>>   
>>   #ifndef __ASSEMBLY__
>>   
>> -#include <asm/page.h>
>> -
>>   #define KASAN_SHADOW_SCALE_SHIFT	3
>>   
>>   #define KASAN_SHADOW_START	(KASAN_SHADOW_OFFSET + \
>>   				 (PAGE_OFFSET >> KASAN_SHADOW_SCALE_SHIFT))
>>   
>> +#ifdef CONFIG_KASAN_SHADOW_OFFSET
>>   #define KASAN_SHADOW_OFFSET	ASM_CONST(CONFIG_KASAN_SHADOW_OFFSET)
>> +#endif
>>   
>> +#ifdef CONFIG_PPC32
>>   #define KASAN_SHADOW_END	0UL
>>   
>> -#define KASAN_SHADOW_SIZE	(KASAN_SHADOW_END - KASAN_SHADOW_START)
>> +#ifdef CONFIG_KASAN
>> +void kasan_late_init(void);
>> +#else
>> +static inline void kasan_late_init(void) { }
>> +#endif
>> +
>> +#endif
>> +
>> +#ifdef CONFIG_PPC_BOOK3S_64
>> +#define KASAN_SHADOW_END	(KASAN_SHADOW_OFFSET + \
>> +				 (RADIX_VMEMMAP_END >> KASAN_SHADOW_SCALE_SHIFT))
>> +
>> +static inline void kasan_late_init(void) { }
>> +#endif
>>   
>>   #ifdef CONFIG_KASAN
>>   void kasan_early_init(void);
>>   void kasan_mmu_init(void);
>>   void kasan_init(void);
>> -void kasan_late_init(void);
>>   #else
>>   static inline void kasan_init(void) { }
>>   static inline void kasan_mmu_init(void) { }
>> -static inline void kasan_late_init(void) { }
>>   #endif
>
> Why modify all this kasan_late_init() stuff ?
>
> This function is only called from kasan init_32.c, it is never called by 
> PPC64, so you should not need to modify anything at all.

I got a compile error for a missing symbol. I'll repro it and attach it.

Regards,
Daniel

> Christophe