On 03.05.21 14:12, David Hildenbrand wrote:
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: Heiko Carstens <hca@xxxxxxxxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Cc: Christian Borntraeger <borntraeger@xxxxxxxxxx> Cc: Sven Schnelle <svens@xxxxxxxxxxxxx> Cc: Alexander Egorenkov <egorenar@xxxxxxxxxxxxx> Cc: Niklas Schnelle <schnelle@xxxxxxxxxxxxx> Cc: Janosch Frank <frankja@xxxxxxxxxxxxx> Cc: linux-s390@xxxxxxxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Yes looks correct. This should not be noticable on real machines as you either have both or none, but of course with virtual machine this could happen. Reviewed-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
--- arch/s390/kernel/setup.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index 72134f9f6ff5..5aab59ad5688 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -937,9 +937,9 @@ 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))