git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From b208108638c4bd3215792415944467c36f5dfd97 Mon Sep 17 00:00:00 2001
   2 From: David Hildenbrand <david@redhat.com>
   3 Date: Mon, 3 May 2021 14:12:44 +0200
   4 Subject: s390: fix detection of vector enhancements facility 1 vs. vector packed decimal facility
   5
   6 From: David Hildenbrand <david@redhat.com>
   7
   8 commit b208108638c4bd3215792415944467c36f5dfd97 upstream.
   9
  10 The PoP documents:
  11         134: The vector packed decimal facility is installed in the
  12              z/Architecture architectural mode. When bit 134 is
  13              one, bit 129 is also one.
  14         135: The vector enhancements facility 1 is installed in
  15              the z/Architecture architectural mode. When bit 135
  16              is one, bit 129 is also one.
  17
  18 Looks like we confuse the vector enhancements facility 1 ("EXT") with the
  19 Vector packed decimal facility ("BCD"). Let's fix the facility checks.
  20
  21 Detected while working on QEMU/tcg z14 support and only unlocking
  22 the vector enhancements facility 1, but not the vector packed decimal
  23 facility.
  24
  25 Fixes: 2583b848cad0 ("s390: report new vector facilities")
  26 Cc: Vasily Gorbik <gor@linux.ibm.com>
  27 Signed-off-by: David Hildenbrand <david@redhat.com>
  28 Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
  29 Reviewed-by: Cornelia Huck <cohuck@redhat.com>
  30 Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
  31 Link: https://lore.kernel.org/r/20210503121244.25232-1-david@redhat.com
  32 Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
  33 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  34 ---
  35  arch/s390/kernel/setup.c |    4 ++--
  36  1 file changed, 2 insertions(+), 2 deletions(-)
  37
  38 --- a/arch/s390/kernel/setup.c
  39 +++ b/arch/s390/kernel/setup.c
  40 @@ -937,9 +937,9 @@ static int __init setup_hwcaps(void)
  41         if (MACHINE_HAS_VX) {
  42                 elf_hwcap |= HWCAP_S390_VXRS;
  43                 if (test_facility(134))
  44 -                       elf_hwcap |= HWCAP_S390_VXRS_EXT;
  45 -               if (test_facility(135))
  46                         elf_hwcap |= HWCAP_S390_VXRS_BCD;
  47 +               if (test_facility(135))
  48 +                       elf_hwcap |= HWCAP_S390_VXRS_EXT;
  49                 if (test_facility(148))
  50                         elf_hwcap |= HWCAP_S390_VXRS_EXT2;
  51                 if (test_facility(152))