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| author |   Christian Borntraeger <borntraeger@de.ibm.com> | 2018-11-09 09:21:47 +0100 |
|---|---|---|
| committer |   Martin Schwidefsky <schwidefsky@de.ibm.com> | 2019-01-11 17:12:02 +0100 |
| commit | 03aa047ef2db4985e444af6ee1c1dd084ad9fb4c (patch) | |
| tree | 19559ab083af023a5cf08c3b85b7e2c17c99307c /arch/s390/kernel/early.c | |
| parent | Merge tag 'vfio-v5.0-rc2' of git://github.com/awilliam/linux-vfio (diff) | |
| download | linux-dev-03aa047ef2db4985e444af6ee1c1dd084ad9fb4c.tar.xz linux-dev-03aa047ef2db4985e444af6ee1c1dd084ad9fb4c.zip | |
s390/early: improve machine detection
Right now the early machine detection code check stsi 3.2.2 for "KVM"
and set MACHINE_IS_VM if this is different. As the console detection
uses diagnose 8 if MACHINE_IS_VM returns true this will crash Linux
early for any non z/VM system that sets a different value than KVM.
So instead of assuming z/VM, do not set any of MACHINE_IS_LPAR,
MACHINE_IS_VM, or MACHINE_IS_KVM.
CC: stable@vger.kernel.org
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/kernel/early.c')
| -rw-r--r-- | arch/s390/kernel/early.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c index af5c2b3f7065..a8c7789b246b 100644 --- a/arch/s390/kernel/early.c +++ b/arch/s390/kernel/early.c @@ -63,10 +63,10 @@ static noinline __init void detect_machine_type(void) if (stsi(vmms, 3, 2, 2) || !vmms->count) return; - /* Running under KVM? If not we assume z/VM */ + /* Detect known hypervisors */ if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3)) S390_lowcore.machine_flags |= MACHINE_FLAG_KVM; - else + else if (!memcmp(vmms->vm[0].cpi, "\xa9\x61\xe5\xd4", 4)) S390_lowcore.machine_flags |= MACHINE_FLAG_VM; } |