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 08:13:43 +0100 |
| commit | bd9759a4a4e264988dd54864a54710d5cf98a3b6 (patch) | |
| tree | 21c26ef22fb351d4a3dfc4ed29a27f8a22c0fd03 /arch/s390 | |
| parent | 04af9475e2e6732ffc8a534ed53f72e261b952a0 (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 a3219837fa70..4ba5ad44a21a 100644 --- a/arch/s390/kernel/early.c +++ b/arch/s390/kernel/early.c @@ -226,10 +226,10 @@ 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 98c1f7941142..3cb71fc94995 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -884,6 +884,8 @@ 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 */ |