| Message ID | 20220126092602.1425-1-linmiaohe@huawei.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm/memremap: avoid calling kasan_remove_zero_shadow() for device private memory | expand |
On Wed, Jan 26, 2022 at 5:27 PM Miaohe Lin <linmiaohe@huawei.com> wrote: > > 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. > > Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Good catch. Reviewed-by: Muchun Song <songmuchun@bytedance.com>
diff --git a/mm/memremap.c b/mm/memremap.c index d2a72cf2ff83..d9e05952fff6 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -302,7 +302,8 @@ static int pagemap_range(struct dev_pagemap *pgmap, struct mhp_params *params, 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:
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. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> --- mm/memremap.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)