s390/mm,pageattr: fix walk_pte_level() early exit

In case of splitting to 4k mapping the early exit in walk_pte_level()
must only be taken iff flags is equal to SET_MEMORY_4K.
Currently the early exit is taken if the flag is set, and also others
might be set. This may lead to the situation that a mapping is split
but other changes are not done, like e.g. setting pages to R/W.

There is currently no such caller, but there might be in the future.

Fixes: b3e1a00c8f ("s390/mm: implement set_memory_4k()")
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
This commit is contained in:
Heiko Carstens 2021-08-24 15:21:44 +02:00
parent 8b5f08b484
commit c4f0e5cfde

View File

@ -86,7 +86,7 @@ static int walk_pte_level(pmd_t *pmdp, unsigned long addr, unsigned long end,
{
pte_t *ptep, new;
if ((flags & SET_MEMORY_4K) == SET_MEMORY_4K)
if (flags == SET_MEMORY_4K)
return 0;
ptep = pte_offset_kernel(pmdp, addr);
do {