s390: fix detection of vector enhancements facility 1 vs. vector packed decimal facility

BugLink: https://bugs.launchpad.net/bugs/1929455
commit b208108638c4bd3215792415944467c36f5dfd97 upstream.

The PoP documents:
	134: The vector packed decimal facility is installed in the
	     z/Architecture architectural mode. When bit 134 is
	     one, bit 129 is also one.
	135: The vector enhancements facility 1 is installed in
	     the z/Architecture architectural mode. When bit 135
	     is one, bit 129 is also one.

Looks like we confuse the vector enhancements facility 1 ("EXT") with the
Vector packed decimal facility ("BCD"). Let's fix the facility checks.

Detected while working on QEMU/tcg z14 support and only unlocking
the vector enhancements facility 1, but not the vector packed decimal
facility.

Fixes: 2583b848cad0 ("s390: report new vector facilities")
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20210503121244.25232-1-david@redhat.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 73f5724342b16a2ae3a3e1f99c95dc77a7b5a4c7..66758c16d665c26fc5c5ab1babe0dcb6281881f5 100644 (file)
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -925,9 +925,9 @@ static int __init setup_hwcaps(void)
        if (MACHINE_HAS_VX) {
                elf_hwcap |= HWCAP_S390_VXRS;
                if (test_facility(134))
-                       elf_hwcap |= HWCAP_S390_VXRS_EXT;
-               if (test_facility(135))
                        elf_hwcap |= HWCAP_S390_VXRS_BCD;
+               if (test_facility(135))
+                       elf_hwcap |= HWCAP_S390_VXRS_EXT;
                if (test_facility(148))
                        elf_hwcap |= HWCAP_S390_VXRS_EXT2;
                if (test_facility(152))