On Mon, Dec 20, 2021 at 11:02 PM [off-list ref] wrote:

From: Andrey Konovalov <redacted>

Make KASAN unpoison vmalloc mappings after they have been mapped in
when it's possible: for vmalloc() (indentified via VM_ALLOC) and
vm_map_ram().

The reasons for this are:

- For vmalloc() and vm_map_ram(): pages don't get unpoisoned in case
  mapping them fails.
- For vmalloc(): HW_TAGS KASAN needs pages to be mapped to set tags via
  kasan_unpoison_vmalloc().

As a part of these changes, the return value of __vmalloc_node_range()
is changed to area->addr. This is a non-functional change, as
__vmalloc_area_node() returns area->addr anyway.

Signed-off-by: Andrey Konovalov <redacted>

Reviewed-by: Alexander Potapenko <glider@google.com>