shmem: minor fixes to splice-read implementation

HWPoison: my reading of folio_test_hwpoison() is that it only tests the
head page of a large folio, whereas splice_folio_into_pipe() will splice
as much of the folio as it can: so for safety we should also check the
has_hwpoisoned flag, set if any of the folio's pages are hwpoisoned. 
(Perhaps that ugliness can be improved at the mm end later.)

The call to splice_zeropage_into_pipe() risked overrunning past EOF: ask
it for "part" not "len".

Link: https://lkml.kernel.org/r/[email protected]
Fixes: bd194b187115 ("shmem: Implement splice-read")
Signed-off-by: Hugh Dickins <[email protected]>
Reviewed-by: David Howells <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Jens Axboe <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions