diff options
| author | Christian Borntraeger <borntraeger@de.ibm.com> | 2018-11-09 09:21:47 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-02-06 19:43:03 +0100 |
| commit | 74be2fcda651e596fe4e96c3c1ae4d76aa683655 (patch) | |
| tree | 9b6f42a51093cd2e4e996737459c30cdbb2e2b03 /arch | |
| parent | c25a126d1a651a07dcdddc8f8eb3ef8c01fec932 (diff) | |
s390/early: improve machine detection
commit 03aa047ef2db4985e444af6ee1c1dd084ad9fb4c upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/s390/kernel/early.c | 4 | ||||
| -rw-r--r-- | arch/s390/kernel/setup.c | 2 |
2 files changed, 4 insertions, 2 deletions
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c index 8eccead675d4..cc7b450a7766 100644 --- a/arch/s390/kernel/early.c +++ b/arch/s390/kernel/early.c @@ -224,10 +224,10 @@ 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; } diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index e7a43a30e3ff..47692c78d09c 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -833,6 +833,8 @@ void __init setup_arch(char **cmdline_p) pr_info("Linux is running under KVM in 64-bit mode\n"); else if (MACHINE_IS_LPAR) pr_info("Linux is running natively in 64-bit mode\n"); + else + pr_info("Linux is running as a guest in 64-bit mode\n"); /* Have one command line that is parsed and saved in /proc/cmdline */ /* boot_command_line has been already set up in early.c */ |