Commit 490a5e99 authored by Vasily Gorbik's avatar Vasily Gorbik Committed by Alexander Gordeev
Browse files

s390/boot: Allow KASAN mapping to fallback to small pages 



For KASAN shadow mappings, switch from physmem_alloc_or_die() to
physmem_alloc() and return INVALID_PHYS_ADDR on allocation failure. This
allows gracefully falling back from large pages to smaller pages (1MB
or 4KB) if the allocation of 2GB size/aligned pages cannot be fulfilled.

Reviewed-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
parent aeb4358a

arch/s390/boot/vmem.c

+7 −3
Original line number Diff line number Diff line
@@ -247,9 +247,13 @@ static unsigned long resolve_pa_may_alloc(unsigned long addr, unsigned long size 
		return __identity_pa(addr);

#ifdef CONFIG_KASAN

	case POPULATE_KASAN_MAP_SHADOW:

		addr = physmem_alloc_or_die(RR_VMEM, size, size);

		/* Allow to fail large page allocations, this will fall back to 1mb/4k pages */

		addr = physmem_alloc(RR_VMEM, size, size, size == PAGE_SIZE);

		if (addr) {

			memset((void *)addr, 0, size);

			return addr;

		}

		return INVALID_PHYS_ADDR;

#endif

	default:

		return INVALID_PHYS_ADDR;