diff options
| author | Huacai Chen <chenhc@lemote.com> | 2020-09-10 18:33:51 +0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-09-11 13:22:52 -0400 |
| commit | 15e9e35cd1dec2bc138464de6bf8ef828df19235 (patch) | |
| tree | f3111c1722ecea4875fdd8030a551aeae814c321 | |
| parent | f6f6195b888c28a0b59ceb0562daff92a2be86c3 (diff) | |
KVM: MIPS: Change the definition of kvm type
MIPS defines two kvm types:
#define KVM_VM_MIPS_TE 0
#define KVM_VM_MIPS_VZ 1
In Documentation/virt/kvm/api.rst it is said that "You probably want to
use 0 as machine type", which implies that type 0 be the "automatic" or
"default" type. And, in user-space libvirt use the null-machine (with
type 0) to detect the kvm capability, which returns "KVM not supported"
on a VZ platform.
I try to fix it in QEMU but it is ugly:
https://lists.nongnu.org/archive/html/qemu-devel/2020-08/msg05629.html
And Thomas Huth suggests me to change the definition of kvm type:
https://lists.nongnu.org/archive/html/qemu-devel/2020-09/msg03281.html
So I define like this:
#define KVM_VM_MIPS_AUTO 0
#define KVM_VM_MIPS_VZ 1
#define KVM_VM_MIPS_TE 2
Since VZ and TE cannot co-exists, using type 0 on a TE platform will
still return success (so old user-space tools have no problems on new
kernels); the advantage is that using type 0 on a VZ platform will not
return failure. So, the only problem is "new user-space tools use type
2 on old kernels", but if we treat this as a kernel bug, we can backport
this patch to old stable kernels.
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Message-Id: <1599734031-28746-1-git-send-email-chenhc@lemote.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/mips/kvm/mips.c | 2 | ||||
| -rw-r--r-- | include/uapi/linux/kvm.h | 5 |
2 files changed, 5 insertions, 2 deletions
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c index 7de85d2253ff..0c50ac444222 100644 --- a/arch/mips/kvm/mips.c +++ b/arch/mips/kvm/mips.c @@ -137,6 +137,8 @@ extern void kvm_init_loongson_ipi(struct kvm *kvm); int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { switch (type) { + case KVM_VM_MIPS_AUTO: + break; #ifdef CONFIG_KVM_MIPS_VZ case KVM_VM_MIPS_VZ: #else diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 3d8023474f2a..7d8eced6f459 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -790,9 +790,10 @@ struct kvm_ppc_resize_hpt { #define KVM_VM_PPC_HV 1 #define KVM_VM_PPC_PR 2 -/* on MIPS, 0 forces trap & emulate, 1 forces VZ ASE */ -#define KVM_VM_MIPS_TE 0 +/* on MIPS, 0 indicates auto, 1 forces VZ ASE, 2 forces trap & emulate */ +#define KVM_VM_MIPS_AUTO 0 #define KVM_VM_MIPS_VZ 1 +#define KVM_VM_MIPS_TE 2 #define KVM_S390_SIE_PAGE_OFFSET 1 |