2014-07-12 4:59 GMT+04:00 H. Peter Anvin <hpa@xxxxxxxxx>: > 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? > Sparsemem configurations currently may not work with kasan. I suppose I will have to move shadow area to vmalloc address space and make it (shadow) sparse too if needed. > -hpa > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@xxxxxxxxx. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a> -- Best regards, Andrey Ryabinin -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html