Commit 3e4352ae authored Jul 09, 2020 by Aneesh Kumar K.V Committed by Michael Ellerman Jul 20, 2020

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

parent 3c8ab473

arch/powerpc/mm/book3s64/pkeys.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -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));
		}