mm/madvise: add MF_ACTION_REQUIRED to madvise(MADV_HWPOISON)

mm/madvise: add MF_ACTION_REQUIRED to madvise(MADV_HWPOISON)

The soft hwpoison injector via madvise(MADV_HWPOISON) operates in a
synchrous way in a sense, the injector is also a process under test, and
should it have the poisoned page mapped in its address space, it should
get killed as much as in a real UE situation.  Doing so align with what
the madvise(2) man page says: " "This operation may result in the calling
process receiving a SIGBUS and the page being unmapped."

Link: https://lkml.kernel.org/r/20240524215306.2705454-3-jane.chu@oracle.com
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Reviewed-by: Oscar Salvador <oalvador@suse.de>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>