Re: [PATCH 2/2] kvm: rename KVM_MAX_VCPU_ID to, KVM_MAX_VCPU_IDS
On 14 September 2021 at 05:59 pm, Christian Zigotzky wrote: Hello Juergen, Hello All, Since the RC1 of kernel 5.13, -smp 2 and -smp 4 don't work with a virtual e5500 QEMU KVM-HV machine anymore. [1] I see in the serial console, that the uImage doesn't load. I use the following QEMU command for booting: qemu-system-ppc64 -M ppce500 -cpu e5500 -enable-kvm -m 1024 -kernel uImage -drive format=raw,file=MintPPC32-X5000.img,index=0,if=virtio -netdev user,id=mynet0 -device virtio-net,netdev=mynet0 -append "rw root=/dev/vda" -device virtio-vga -device virtio-mouse-pci -device virtio-keyboard-pci -device pci-ohci,id=newusb -device usb-audio,bus=newusb.0 -smp 4 The kernels boot without KVM-HV. Summary for KVM-HV: -smp 1 -> works -smp 2 -> doesn't work -smp 3 -> works -smp 4 -> doesn't work I used -smp 4 before the RC1 of kernel 5.13 because my FSL P5040 BookE machine [2] has 4 cores. Does this patch solve this issue? [3] Thanks, Christian [1] https://lists.ozlabs.org/pipermail/linuxppc-dev/2021-May/229103.html [2] http://wiki.amiga.org/index.php?title=X5000 [3] https://lists.ozlabs.org/pipermail/linuxppc-dev/2021-September/234152.html Hello, Since the RC5 of kernel 5.19, -smp 2 and -smp 4 work again. I don't know which patch has solved the issue. Cheers, Christian
Re: [PATCH 2/2] kvm: rename KVM_MAX_VCPU_ID to, KVM_MAX_VCPU_IDS
Hello Juergen, Hello All, Since the RC1 of kernel 5.13, -smp 2 and -smp 4 don't work with a virtual e5500 QEMU KVM-HV machine anymore. [1] I see in the serial console, that the uImage doesn't load. I use the following QEMU command for booting: qemu-system-ppc64 -M ppce500 -cpu e5500 -enable-kvm -m 1024 -kernel uImage -drive format=raw,file=MintPPC32-X5000.img,index=0,if=virtio -netdev user,id=mynet0 -device virtio-net,netdev=mynet0 -append "rw root=/dev/vda" -device virtio-vga -device virtio-mouse-pci -device virtio-keyboard-pci -device pci-ohci,id=newusb -device usb-audio,bus=newusb.0 -smp 4 The kernels boot without KVM-HV. Summary for KVM-HV: -smp 1 -> works -smp 2 -> doesn't work -smp 3 -> works -smp 4 -> doesn't work I used -smp 4 before the RC1 of kernel 5.13 because my FSL P5040 BookE machine [2] has 4 cores. Does this patch solve this issue? [3] Thanks, Christian [1] https://lists.ozlabs.org/pipermail/linuxppc-dev/2021-May/229103.html [2] http://wiki.amiga.org/index.php?title=X5000 [3] https://lists.ozlabs.org/pipermail/linuxppc-dev/2021-September/234152.html
Re: [PATCH 2/2] kvm: rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS
On Mon, Sep 13, 2021 at 12:24 PM Sean Christopherson wrote: > > On Mon, Sep 13, 2021, Juergen Gross wrote: > > KVM_MAX_VCPU_ID is not specifying the highest allowed vcpu-id, but the > > number of allowed vcpu-ids. This has already led to confusion, so > > rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS to make its semantics more > > clear > > My hesitation with this rename is that the max _number_ of IDs is not the same > thing as the max allowed ID. E.g. on x86, given a capability that enumerates > the > max number of IDs, I would expect to be able to create vCPUs with arbitrary > 32-bit > x2APIC IDs so long as the total number of IDs is below the max. > What name would you suggest instead? KVM_VCPU_ID_LIMIT, maybe? I'm assuming we are not going to redefine KVM_MAX_VCPU_ID to be an inclusive limit. -- Eduardo
Re: [PATCH 2/2] kvm: rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS
On Mon, Sep 13, 2021, Eduardo Habkost wrote: > On Mon, Sep 13, 2021 at 12:24 PM Sean Christopherson > wrote: > > > > On Mon, Sep 13, 2021, Juergen Gross wrote: > > > KVM_MAX_VCPU_ID is not specifying the highest allowed vcpu-id, but the > > > number of allowed vcpu-ids. This has already led to confusion, so > > > rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS to make its semantics more > > > clear > > > > My hesitation with this rename is that the max _number_ of IDs is not the > > same > > thing as the max allowed ID. E.g. on x86, given a capability that > > enumerates the > > max number of IDs, I would expect to be able to create vCPUs with arbitrary > > 32-bit > > x2APIC IDs so long as the total number of IDs is below the max. > > > > What name would you suggest instead? KVM_VCPU_ID_LIMIT, maybe? > > I'm assuming we are not going to redefine KVM_MAX_VCPU_ID to be an > inclusive limit. Heh, I haven't been able to come up with one, which is why I suggested the route of making it an inclusive value internally within KVM.
Re: [PATCH 2/2] kvm: rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS
On Mon, Sep 13, 2021, Juergen Gross wrote: > KVM_MAX_VCPU_ID is not specifying the highest allowed vcpu-id, but the > number of allowed vcpu-ids. This has already led to confusion, so > rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS to make its semantics more > clear My hesitation with this rename is that the max _number_ of IDs is not the same thing as the max allowed ID. E.g. on x86, given a capability that enumerates the max number of IDs, I would expect to be able to create vCPUs with arbitrary 32-bit x2APIC IDs so long as the total number of IDs is below the max.
[PATCH 2/2] kvm: rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS
KVM_MAX_VCPU_ID is not specifying the highest allowed vcpu-id, but the
number of allowed vcpu-ids. This has already led to confusion, so
rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS to make its semantics more
clear
Suggested-by: Eduardo Habkost
Signed-off-by: Juergen Gross
---
Documentation/virt/kvm/devices/xics.rst| 2 +-
Documentation/virt/kvm/devices/xive.rst| 2 +-
arch/mips/kvm/mips.c | 2 +-
arch/powerpc/include/asm/kvm_book3s.h | 2 +-
arch/powerpc/include/asm/kvm_host.h| 4 ++--
arch/powerpc/kvm/book3s_xive.c | 2 +-
arch/powerpc/kvm/powerpc.c | 2 +-
arch/x86/include/asm/kvm_host.h| 2 +-
arch/x86/kvm/ioapic.c | 2 +-
arch/x86/kvm/ioapic.h | 4 ++--
arch/x86/kvm/x86.c | 2 +-
include/linux/kvm_host.h | 4 ++--
tools/testing/selftests/kvm/kvm_create_max_vcpus.c | 2 +-
virt/kvm/kvm_main.c| 2 +-
14 files changed, 17 insertions(+), 17 deletions(-)
diff --git a/Documentation/virt/kvm/devices/xics.rst
b/Documentation/virt/kvm/devices/xics.rst
index 2d6927e0b776..bf32c77174ab 100644
--- a/Documentation/virt/kvm/devices/xics.rst
+++ b/Documentation/virt/kvm/devices/xics.rst
@@ -22,7 +22,7 @@ Groups:
Errors:
=== ==
--EINVAL Value greater than KVM_MAX_VCPU_ID.
+-EINVAL Value greater than KVM_MAX_VCPU_IDS.
-EFAULT Invalid user pointer for attr->addr.
-EBUSY A vcpu is already connected to the device.
=== ==
diff --git a/Documentation/virt/kvm/devices/xive.rst
b/Documentation/virt/kvm/devices/xive.rst
index 8bdf3dc38f01..8b5e7b40bdf8 100644
--- a/Documentation/virt/kvm/devices/xive.rst
+++ b/Documentation/virt/kvm/devices/xive.rst
@@ -91,7 +91,7 @@ the legacy interrupt mode, referred as XICS (POWER7/8).
Errors:
=== ==
- -EINVAL Value greater than KVM_MAX_VCPU_ID.
+ -EINVAL Value greater than KVM_MAX_VCPU_IDS.
-EFAULT Invalid user pointer for attr->addr.
-EBUSY A vCPU is already connected to the device.
=== ==
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 75c6f264c626..562aa878b266 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -1073,7 +1073,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long
ext)
r = KVM_MAX_VCPUS;
break;
case KVM_CAP_MAX_VCPU_ID:
- r = KVM_MAX_VCPU_ID;
+ r = KVM_MAX_VCPU_IDS;
break;
case KVM_CAP_MIPS_FPU:
/* We don't handle systems with inconsistent cpu_has_fpu */
diff --git a/arch/powerpc/include/asm/kvm_book3s.h
b/arch/powerpc/include/asm/kvm_book3s.h
index caaa0f592d8e..3d31f2c59e43 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -434,7 +434,7 @@ extern int kvmppc_h_logical_ci_store(struct kvm_vcpu *vcpu);
#define SPLIT_HACK_OFFS0xfb00
/*
- * This packs a VCPU ID from the [0..KVM_MAX_VCPU_ID) space down to the
+ * This packs a VCPU ID from the [0..KVM_MAX_VCPU_IDS) space down to the
* [0..KVM_MAX_VCPUS) space, using knowledge of the guest's core stride
* (but not its actual threading mode, which is not available) to avoid
* collisions.
diff --git a/arch/powerpc/include/asm/kvm_host.h
b/arch/powerpc/include/asm/kvm_host.h
index 080a7feb7731..59cb38b04ede 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -33,11 +33,11 @@
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
#include /* for MAX_SMT_THREADS */
-#define KVM_MAX_VCPU_ID(MAX_SMT_THREADS * KVM_MAX_VCORES)
+#define KVM_MAX_VCPU_IDS (MAX_SMT_THREADS * KVM_MAX_VCORES)
#define KVM_MAX_NESTED_GUESTS KVMPPC_NR_LPIDS
#else
-#define KVM_MAX_VCPU_IDKVM_MAX_VCPUS
+#define KVM_MAX_VCPU_IDS KVM_MAX_VCPUS
#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
#define __KVM_HAVE_ARCH_INTC_INITIALIZED
diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c
index a18db9e16ea4..225008882958 100644
--- a/arch/powerpc/kvm/book3s_xive.c
+++ b/arch/powerpc/kvm/book3s_xive.c
@@ -1928,7 +1928,7 @@ int kvmppc_xive_set_nr_servers(struct kvmppc_xive *xive,
u64 addr)
pr_devel("%s nr_servers=%u\n", __func__, nr_servers);
- if (!nr_servers || nr_servers > KVM_MAX_VCPU_ID)
+ if (!nr_servers || nr_servers > KVM_MAX_VCPU_IDS)
return -EINVAL;
mutex_lock(>lock);
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index b4e6f70b97b9..8ab90ce8738f 100644
--- a/arch/powerpc/kvm/powerpc.c
+++
