Messages in this thread | | | Date | Fri, 11 Jul 2014 17:59:34 -0700 | From | "H. Peter Anvin" <> | Subject | Re: [RFC/PATCH -next 00/21] Address sanitizer for kernel (kasan) - dynamic memory error detector. |
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On 07/09/2014 04:00 AM, Andrey Ryabinin wrote: > > Address sanitizer dedicates 1/8 of the low memory to the shadow memory and uses direct > mapping with a scale and offset to translate a memory address to its corresponding > shadow address. > > Here is function to translate address to corresponding shadow address: > > unsigned long kasan_mem_to_shadow(unsigned long addr) > { > return ((addr) >> KASAN_SHADOW_SCALE_SHIFT) > + kasan_shadow_start - (PAGE_OFFSET >> KASAN_SHADOW_SCALE_SHIFT); > } > > where KASAN_SHADOW_SCALE_SHIFT = 3. >
How does that work when memory is sparsely populated?
-hpa
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