powerpc/book3s64/pkeys: Mark all the pkeys above max pkey as reserved

The hypervisor can return less than max allowed pkey (for ex: 31) instead
of 32. We should mark all the pkeys above max allowed as reserved so
that we avoid the allocation of the wrong pkey(for ex: key 31 in the above
case) by userspace.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200709032946.881753-13-aneesh.kumar@linux.ibm.com
This commit is contained in:
Aneesh Kumar K.V 2020-07-09 08:59:35 +05:30 committed by Michael Ellerman
parent 3c8ab47362
commit 3e4352aeb8

View File

@ -189,9 +189,10 @@ static int pkey_initialize(void)
/*
* Prevent the usage of OS reserved keys. Update UAMOR
* for those keys.
* for those keys. Also mark the rest of the bits in the
* 32 bit mask as reserved.
*/
for (i = num_pkey; i < pkeys_total; i++) {
for (i = num_pkey; i < 32 ; i++) {
reserved_allocation_mask |= (0x1 << i);
default_uamor &= ~(0x3ul << pkeyshift(i));
}