mm/gup: Let __get_user_pages_locked() return -EINTR for fatal signal

mm/gup: Let __get_user_pages_locked() return -EINTR for fatal signal

__get_user_pages_locked() will return 0 instead of -EINTR after commit
4426e945df588 ("mm/gup: allow VM_FAULT_RETRY for multiple times") which
added extra code to allow gup detect fatal signal faster.

Restore the original -EINTR behavior.

Cc: Andrew Morton <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Fixes: 4426e945df58 ("mm/gup: allow VM_FAULT_RETRY for multiple times")
Reported-by: [email protected]
Signed-off-by: Hillf Danton <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Signed-off-by: Peter Xu <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>