KASAN shadow map doesn't need to be accessible through the linear kernel mapping, allocate its pages with MEMBLOCK_ALLOC_ANYWHERE so that high memory can be used. This frees up to ~100MB of low memory on xtensa configurations with KASAN and high memory.
Cc: stable@vger.kernel.org # v5.1+ Fixes: f240ec09bb8a ("memblock: replace memblock_alloc_base(ANYWHERE) with memblock_phys_alloc") Signed-off-by: Max Filippov jcmvbkbc@gmail.com --- arch/xtensa/mm/kasan_init.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/xtensa/mm/kasan_init.c b/arch/xtensa/mm/kasan_init.c index 9c957791bb33..e3baa21ff24c 100644 --- a/arch/xtensa/mm/kasan_init.c +++ b/arch/xtensa/mm/kasan_init.c @@ -60,7 +60,9 @@ static void __init populate(void *start, void *end)
for (k = 0; k < PTRS_PER_PTE; ++k, ++j) { phys_addr_t phys = - memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); + memblock_phys_alloc_range(PAGE_SIZE, PAGE_SIZE, + 0, + MEMBLOCK_ALLOC_ANYWHERE);
if (!phys) panic("Failed to allocate page table page\n");