On Tue, 2018-08-21 at 13:03:23 UTC, Christophe Leroy wrote:
Commit 5769beaf180a8 ("powerpc/mm: Add proper pte access check helper for other platforms") replaced generic pte_access_permitted() by an arch specific one.
The generic one is defined as (pte_present(pte) && (!(write) || pte_write(pte)))
The arch specific one is open coded checking that _PAGE_USER and _PAGE_WRITE (_PAGE_RW) flags are set, but lacking to check that _PAGE_RO and _PAGE_PRIVILEGED are unset, leading to a useless test on targets like the 8xx which defines _PAGE_RW and _PAGE_USER as 0.
Commit 5fa5b16be5b31 ("powerpc/mm/hugetlb: Use pte_access_permitted for hugetlb access check") replaced some tests performed with pte helpers by a call to pte_access_permitted(), leading to the same issue.
This patch rewrites powerpc/nohash pte_access_permitted() using pte helpers.
Fixes: 5769beaf180a8 ("powerpc/mm: Add proper pte access check helper for other platforms") Fixes: 5fa5b16be5b31 ("powerpc/mm/hugetlb: Use pte_access_permitted for hugetlb access check") Cc: stable@vger.kernel.org # v4.15+ Signed-off-by: Christophe Leroy christophe.leroy@c-s.fr Reviewed-by: Aneesh Kumar K.V aneesh.kumar@linux.ibm.com
Applied to powerpc next, thanks.
https://git.kernel.org/powerpc/c/810e9f86f36f59f1d6f6710220c49a
cheers