diff options
| author | Christian Borntraeger <borntraeger@de.ibm.com> | 2018-11-09 09:21:47 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-01-31 08:12:34 +0100 |
| commit | 17eb3c3efb0eb74eb7da71fc1e1eec99c1b7089c (patch) | |
| tree | 410ee57342b31793b0ac8607031d9e661dd71ed9 /arch/s390 | |
| parent | d894089996197bee258a6792da9f45af35dab099 (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/s390')
| -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 0c7a7d5d95f1..a651c2bc94ef 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 feb9d97a9d14..a559908d180e 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -863,6 +863,8 @@ 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 */ |