From: Miaohe Lin <linmiaohe@xxxxxxxxxx> Subject: mm/memremap: avoid calling kasan_remove_zero_shadow() for device private memory For device private memory, we do not create a linear mapping for the memory because the device memory is un-accessible. Thus we do not add kasan zero shadow for it. So it's unnecessary to do kasan_remove_zero_shadow() for it. Link: https://lkml.kernel.org/r/20220126092602.1425-1-linmiaohe@xxxxxxxxxx Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memremap.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/memremap.c~mm-memremap-avoid-calling-kasan_remove_zero_shadow-for-device-private-memory +++ a/mm/memremap.c @@ -282,7 +282,8 @@ static int pagemap_range(struct dev_page return 0; err_add_memory: - kasan_remove_zero_shadow(__va(range->start), range_len(range)); + if (!is_private) + kasan_remove_zero_shadow(__va(range->start), range_len(range)); err_kasan: untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range)); err_pfn_remap: _
