* [PATCH 1/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_send_ipi()
2022-02-22 15:46 [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes Vitaly Kuznetsov
@ 2022-02-22 15:46 ` Vitaly Kuznetsov
2022-02-25 18:21 ` Maxim Levitsky
2022-02-28 10:45 ` Siddharth Chandrasekaran
2022-02-22 15:46 ` [PATCH 2/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_flush_tlb() Vitaly Kuznetsov
` (3 subsequent siblings)
4 siblings, 2 replies; 20+ messages in thread
From: Vitaly Kuznetsov @ 2022-02-22 15:46 UTC (permalink / raw)
To: kvm, Paolo Bonzini
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel
'struct kvm_hv_hcall' has all the required information already,
there's no need to pass 'ex' additionally.
No functional change intended.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
arch/x86/kvm/hyperv.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 6e38a7d22e97..15b6a7bd2346 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1875,7 +1875,7 @@ static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
}
}
-static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
+static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
{
struct kvm *kvm = vcpu->kvm;
struct hv_send_ipi_ex send_ipi_ex;
@@ -1889,7 +1889,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
u32 vector;
bool all_cpus;
- if (!ex) {
+ if (hc->code == HVCALL_SEND_IPI) {
if (!hc->fast) {
if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
sizeof(send_ipi))))
@@ -2279,14 +2279,14 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
- ret = kvm_hv_send_ipi(vcpu, &hc, false);
+ ret = kvm_hv_send_ipi(vcpu, &hc);
break;
case HVCALL_SEND_IPI_EX:
if (unlikely(hc.fast || hc.rep)) {
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
- ret = kvm_hv_send_ipi(vcpu, &hc, true);
+ ret = kvm_hv_send_ipi(vcpu, &hc);
break;
case HVCALL_POST_DEBUG_DATA:
case HVCALL_RETRIEVE_DEBUG_DATA:
--
2.35.1
^ permalink raw reply related [flat|nested] 20+ messages in thread
* Re: [PATCH 1/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_send_ipi()
2022-02-22 15:46 ` [PATCH 1/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_send_ipi() Vitaly Kuznetsov
@ 2022-02-25 18:21 ` Maxim Levitsky
2022-02-28 9:58 ` Vitaly Kuznetsov
2022-02-28 10:45 ` Siddharth Chandrasekaran
1 sibling, 1 reply; 20+ messages in thread
From: Maxim Levitsky @ 2022-02-25 18:21 UTC (permalink / raw)
To: Vitaly Kuznetsov, kvm, Paolo Bonzini
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel
On Tue, 2022-02-22 at 16:46 +0100, Vitaly Kuznetsov wrote:
> 'struct kvm_hv_hcall' has all the required information already,
> there's no need to pass 'ex' additionally.
>
> No functional change intended.
>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
> ---
> arch/x86/kvm/hyperv.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index 6e38a7d22e97..15b6a7bd2346 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -1875,7 +1875,7 @@ static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
> }
> }
>
> -static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
> +static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
> {
> struct kvm *kvm = vcpu->kvm;
> struct hv_send_ipi_ex send_ipi_ex;
> @@ -1889,7 +1889,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
> u32 vector;
> bool all_cpus;
>
> - if (!ex) {
> + if (hc->code == HVCALL_SEND_IPI) {
I am thinking, if we already touch this code,
why not to use switch here instead on the hc->code,
so that we can catch this function being called with something else than
HVCALL_SEND_IPI_EX
> if (!hc->fast) {
> if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
> sizeof(send_ipi))))
> @@ -2279,14 +2279,14 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
> - ret = kvm_hv_send_ipi(vcpu, &hc, false);
> + ret = kvm_hv_send_ipi(vcpu, &hc);
> break;
> case HVCALL_SEND_IPI_EX:
> if (unlikely(hc.fast || hc.rep)) {
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
> - ret = kvm_hv_send_ipi(vcpu, &hc, true);
> + ret = kvm_hv_send_ipi(vcpu, &hc);
> break;
> case HVCALL_POST_DEBUG_DATA:
> case HVCALL_RETRIEVE_DEBUG_DATA:
Other than this minor nitpick:
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Best regards,
Maxim Levitsky
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH 1/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_send_ipi()
2022-02-25 18:21 ` Maxim Levitsky
@ 2022-02-28 9:58 ` Vitaly Kuznetsov
0 siblings, 0 replies; 20+ messages in thread
From: Vitaly Kuznetsov @ 2022-02-28 9:58 UTC (permalink / raw)
To: Maxim Levitsky, kvm
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel, Paolo Bonzini
Maxim Levitsky <mlevitsk@redhat.com> writes:
> On Tue, 2022-02-22 at 16:46 +0100, Vitaly Kuznetsov wrote:
>> 'struct kvm_hv_hcall' has all the required information already,
>> there's no need to pass 'ex' additionally.
>>
>> No functional change intended.
>>
>> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
>> ---
>> arch/x86/kvm/hyperv.c | 8 ++++----
>> 1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
>> index 6e38a7d22e97..15b6a7bd2346 100644
>> --- a/arch/x86/kvm/hyperv.c
>> +++ b/arch/x86/kvm/hyperv.c
>> @@ -1875,7 +1875,7 @@ static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
>> }
>> }
>>
>> -static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
>> +static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
>> {
>> struct kvm *kvm = vcpu->kvm;
>> struct hv_send_ipi_ex send_ipi_ex;
>> @@ -1889,7 +1889,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
>> u32 vector;
>> bool all_cpus;
>>
>> - if (!ex) {
>> + if (hc->code == HVCALL_SEND_IPI) {
>
> I am thinking, if we already touch this code,
> why not to use switch here instead on the hc->code,
> so that we can catch this function being called with something else than
> HVCALL_SEND_IPI_EX
I'm not against this second line of defense but kvm_hv_send_ipi() is
only called explicitly from kvm_hv_hypercall()'s switch so something is
really screwed up if we end up seeing something different from
HVCALL_SEND_IPI_EX/HVCALL_SEND_IPI here.
I'm now working on a bigger series for TLB flush improvements, will use
your suggestion there, thanks!
>
>> if (!hc->fast) {
>> if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
>> sizeof(send_ipi))))
>> @@ -2279,14 +2279,14 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
>> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
>> break;
>> }
>> - ret = kvm_hv_send_ipi(vcpu, &hc, false);
>> + ret = kvm_hv_send_ipi(vcpu, &hc);
>> break;
>> case HVCALL_SEND_IPI_EX:
>> if (unlikely(hc.fast || hc.rep)) {
>> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
>> break;
>> }
>> - ret = kvm_hv_send_ipi(vcpu, &hc, true);
>> + ret = kvm_hv_send_ipi(vcpu, &hc);
>> break;
>> case HVCALL_POST_DEBUG_DATA:
>> case HVCALL_RETRIEVE_DEBUG_DATA:
>
>
>
> Other than this minor nitpick:
>
> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
>
>
> Best regards,
> Maxim Levitsky
>
--
Vitaly
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH 1/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_send_ipi()
2022-02-22 15:46 ` [PATCH 1/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_send_ipi() Vitaly Kuznetsov
2022-02-25 18:21 ` Maxim Levitsky
@ 2022-02-28 10:45 ` Siddharth Chandrasekaran
1 sibling, 0 replies; 20+ messages in thread
From: Siddharth Chandrasekaran @ 2022-02-28 10:45 UTC (permalink / raw)
To: Vitaly Kuznetsov
Cc: kvm, Paolo Bonzini, Sean Christopherson, Wanpeng Li, Jim Mattson,
linux-kernel
On Tue, Feb 22, 2022 at 04:46:39PM +0100, Vitaly Kuznetsov wrote:
> CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.
>
>
>
> 'struct kvm_hv_hcall' has all the required information already,
> there's no need to pass 'ex' additionally.
>
> No functional change intended.
>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Siddharth Chandrasekaran <sidcha@amazon.de>
Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Sitz: Berlin
Ust-ID: DE 289 237 879
^ permalink raw reply [flat|nested] 20+ messages in thread
* [PATCH 2/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_flush_tlb()
2022-02-22 15:46 [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes Vitaly Kuznetsov
2022-02-22 15:46 ` [PATCH 1/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_send_ipi() Vitaly Kuznetsov
@ 2022-02-22 15:46 ` Vitaly Kuznetsov
2022-02-25 18:22 ` Maxim Levitsky
2022-02-28 10:46 ` Siddharth Chandrasekaran
2022-02-22 15:46 ` [PATCH 3/4] KVM: x86: hyper-v: Fix the maximum number of sparse banks for XMM fast TLB flush hypercalls Vitaly Kuznetsov
` (2 subsequent siblings)
4 siblings, 2 replies; 20+ messages in thread
From: Vitaly Kuznetsov @ 2022-02-22 15:46 UTC (permalink / raw)
To: kvm, Paolo Bonzini
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel
'struct kvm_hv_hcall' has all the required information already,
there's no need to pass 'ex' additionally.
No functional change intended.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
arch/x86/kvm/hyperv.c | 23 ++++++-----------------
1 file changed, 6 insertions(+), 17 deletions(-)
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 15b6a7bd2346..714af3b94f31 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1750,7 +1750,7 @@ struct kvm_hv_hcall {
sse128_t xmm[HV_HYPERCALL_MAX_XMM_REGISTERS];
};
-static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
+static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
{
int i;
gpa_t gpa;
@@ -1765,7 +1765,8 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
int sparse_banks_len;
bool all_cpus;
- if (!ex) {
+ if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
+ hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
if (hc->fast) {
flush.address_space = hc->ingpa;
flush.flags = hc->outgpa;
@@ -2247,32 +2248,20 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
kvm_hv_hypercall_complete_userspace;
return 0;
case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
- if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
- ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
- break;
- }
- ret = kvm_hv_flush_tlb(vcpu, &hc, false);
- break;
- case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
- if (unlikely(hc.rep)) {
- ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
- break;
- }
- ret = kvm_hv_flush_tlb(vcpu, &hc, false);
- break;
case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
- ret = kvm_hv_flush_tlb(vcpu, &hc, true);
+ ret = kvm_hv_flush_tlb(vcpu, &hc);
break;
+ case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
if (unlikely(hc.rep)) {
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
- ret = kvm_hv_flush_tlb(vcpu, &hc, true);
+ ret = kvm_hv_flush_tlb(vcpu, &hc);
break;
case HVCALL_SEND_IPI:
if (unlikely(hc.rep)) {
--
2.35.1
^ permalink raw reply related [flat|nested] 20+ messages in thread
* Re: [PATCH 2/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_flush_tlb()
2022-02-22 15:46 ` [PATCH 2/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_flush_tlb() Vitaly Kuznetsov
@ 2022-02-25 18:22 ` Maxim Levitsky
2022-02-28 10:46 ` Siddharth Chandrasekaran
1 sibling, 0 replies; 20+ messages in thread
From: Maxim Levitsky @ 2022-02-25 18:22 UTC (permalink / raw)
To: Vitaly Kuznetsov, kvm, Paolo Bonzini
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel
On Tue, 2022-02-22 at 16:46 +0100, Vitaly Kuznetsov wrote:
> 'struct kvm_hv_hcall' has all the required information already,
> there's no need to pass 'ex' additionally.
>
> No functional change intended.
>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
> ---
> arch/x86/kvm/hyperv.c | 23 ++++++-----------------
> 1 file changed, 6 insertions(+), 17 deletions(-)
>
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index 15b6a7bd2346..714af3b94f31 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -1750,7 +1750,7 @@ struct kvm_hv_hcall {
> sse128_t xmm[HV_HYPERCALL_MAX_XMM_REGISTERS];
> };
>
> -static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
> +static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
> {
> int i;
> gpa_t gpa;
> @@ -1765,7 +1765,8 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
> int sparse_banks_len;
> bool all_cpus;
>
> - if (!ex) {
> + if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
> + hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
> if (hc->fast) {
> flush.address_space = hc->ingpa;
> flush.flags = hc->outgpa;
> @@ -2247,32 +2248,20 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
> kvm_hv_hypercall_complete_userspace;
> return 0;
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
> - if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
> - ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> - break;
> - }
> - ret = kvm_hv_flush_tlb(vcpu, &hc, false);
> - break;
> - case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
> - if (unlikely(hc.rep)) {
> - ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> - break;
> - }
> - ret = kvm_hv_flush_tlb(vcpu, &hc, false);
> - break;
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
> if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
> - ret = kvm_hv_flush_tlb(vcpu, &hc, true);
> + ret = kvm_hv_flush_tlb(vcpu, &hc);
> break;
> + case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
> if (unlikely(hc.rep)) {
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
> - ret = kvm_hv_flush_tlb(vcpu, &hc, true);
> + ret = kvm_hv_flush_tlb(vcpu, &hc);
> break;
> case HVCALL_SEND_IPI:
> if (unlikely(hc.rep)) {
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Best regards,
Maxim Levitsky
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH 2/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_flush_tlb()
2022-02-22 15:46 ` [PATCH 2/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_flush_tlb() Vitaly Kuznetsov
2022-02-25 18:22 ` Maxim Levitsky
@ 2022-02-28 10:46 ` Siddharth Chandrasekaran
1 sibling, 0 replies; 20+ messages in thread
From: Siddharth Chandrasekaran @ 2022-02-28 10:46 UTC (permalink / raw)
To: Vitaly Kuznetsov
Cc: kvm, Paolo Bonzini, Sean Christopherson, Wanpeng Li, Jim Mattson,
linux-kernel
On Tue, Feb 22, 2022 at 04:46:40PM +0100, Vitaly Kuznetsov wrote:
> CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.
>
>
>
> 'struct kvm_hv_hcall' has all the required information already,
> there's no need to pass 'ex' additionally.
>
> No functional change intended.
>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Siddharth Chandrasekaran <sidcha@amazon.de>
Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Sitz: Berlin
Ust-ID: DE 289 237 879
^ permalink raw reply [flat|nested] 20+ messages in thread
* [PATCH 3/4] KVM: x86: hyper-v: Fix the maximum number of sparse banks for XMM fast TLB flush hypercalls
2022-02-22 15:46 [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes Vitaly Kuznetsov
2022-02-22 15:46 ` [PATCH 1/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_send_ipi() Vitaly Kuznetsov
2022-02-22 15:46 ` [PATCH 2/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_flush_tlb() Vitaly Kuznetsov
@ 2022-02-22 15:46 ` Vitaly Kuznetsov
2022-02-28 10:47 ` Siddharth Chandrasekaran
2022-02-22 15:46 ` [PATCH 4/4] KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall Vitaly Kuznetsov
2022-02-25 11:55 ` [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes Paolo Bonzini
4 siblings, 1 reply; 20+ messages in thread
From: Vitaly Kuznetsov @ 2022-02-22 15:46 UTC (permalink / raw)
To: kvm, Paolo Bonzini
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel
When TLB flush hypercalls (HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}_EX are
issued in 'XMM fast' mode, the maximum number of allowed sparse_banks is
not 'HV_HYPERCALL_MAX_XMM_REGISTERS - 1' (5) but twice as many (10) as each
XMM register is 128 bit long and can hold two 64 bit long banks.
Fixes: 5974565bc26d ("KVM: x86: kvm_hv_flush_tlb use inputs from XMM registers")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
arch/x86/kvm/hyperv.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 714af3b94f31..6dda93bf98ae 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1820,7 +1820,8 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
if (!all_cpus) {
if (hc->fast) {
- if (sparse_banks_len > HV_HYPERCALL_MAX_XMM_REGISTERS - 1)
+ /* XMM0 is already consumed, each XMM holds two sparse banks. */
+ if (sparse_banks_len > 2 * (HV_HYPERCALL_MAX_XMM_REGISTERS - 1))
return HV_STATUS_INVALID_HYPERCALL_INPUT;
for (i = 0; i < sparse_banks_len; i += 2) {
sparse_banks[i] = sse128_lo(hc->xmm[i / 2 + 1]);
--
2.35.1
^ permalink raw reply related [flat|nested] 20+ messages in thread
* Re: [PATCH 3/4] KVM: x86: hyper-v: Fix the maximum number of sparse banks for XMM fast TLB flush hypercalls
2022-02-22 15:46 ` [PATCH 3/4] KVM: x86: hyper-v: Fix the maximum number of sparse banks for XMM fast TLB flush hypercalls Vitaly Kuznetsov
@ 2022-02-28 10:47 ` Siddharth Chandrasekaran
0 siblings, 0 replies; 20+ messages in thread
From: Siddharth Chandrasekaran @ 2022-02-28 10:47 UTC (permalink / raw)
To: Vitaly Kuznetsov
Cc: kvm, Paolo Bonzini, Sean Christopherson, Wanpeng Li, Jim Mattson,
linux-kernel
On Tue, Feb 22, 2022 at 04:46:41PM +0100, Vitaly Kuznetsov wrote:
> CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.
>
>
>
> When TLB flush hypercalls (HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}_EX are
> issued in 'XMM fast' mode, the maximum number of allowed sparse_banks is
> not 'HV_HYPERCALL_MAX_XMM_REGISTERS - 1' (5) but twice as many (10) as each
> XMM register is 128 bit long and can hold two 64 bit long banks.
>
> Fixes: 5974565bc26d ("KVM: x86: kvm_hv_flush_tlb use inputs from XMM registers")
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Indeed :)
Reviewed-by: Siddharth Chandrasekaran <sidcha@amazon.de>
Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Sitz: Berlin
Ust-ID: DE 289 237 879
^ permalink raw reply [flat|nested] 20+ messages in thread
* [PATCH 4/4] KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall
2022-02-22 15:46 [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes Vitaly Kuznetsov
` (2 preceding siblings ...)
2022-02-22 15:46 ` [PATCH 3/4] KVM: x86: hyper-v: Fix the maximum number of sparse banks for XMM fast TLB flush hypercalls Vitaly Kuznetsov
@ 2022-02-22 15:46 ` Vitaly Kuznetsov
2022-02-25 18:33 ` Maxim Levitsky
2022-02-28 10:48 ` Siddharth Chandrasekaran
2022-02-25 11:55 ` [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes Paolo Bonzini
4 siblings, 2 replies; 20+ messages in thread
From: Vitaly Kuznetsov @ 2022-02-22 15:46 UTC (permalink / raw)
To: kvm, Paolo Bonzini
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel
It has been proven on practice that at least Windows Server 2019 tries
using HVCALL_SEND_IPI_EX in 'XMM fast' mode when it has more than 64 vCPUs
and it needs to send an IPI to a vCPU > 63. Similarly to other XMM Fast
hypercalls (HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}{,_EX}), this
information is missing in TLFS as of 6.0b. Currently, KVM returns an error
(HV_STATUS_INVALID_HYPERCALL_INPUT) and Windows crashes.
Note, HVCALL_SEND_IPI is a 'standard' fast hypercall (not 'XMM fast') as
all its parameters fit into RDX:R8 and this is handled by KVM correctly.
Fixes: d8f5537a8816 ("KVM: hyper-v: Advertise support for fast XMM hypercalls")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
arch/x86/kvm/hyperv.c | 52 ++++++++++++++++++++++++++++---------------
1 file changed, 34 insertions(+), 18 deletions(-)
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 6dda93bf98ae..3060057bdfd4 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1890,6 +1890,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
int sparse_banks_len;
u32 vector;
bool all_cpus;
+ int i;
if (hc->code == HVCALL_SEND_IPI) {
if (!hc->fast) {
@@ -1910,9 +1911,15 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
} else {
- if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
- sizeof(send_ipi_ex))))
- return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ if (!hc->fast) {
+ if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
+ sizeof(send_ipi_ex))))
+ return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ } else {
+ send_ipi_ex.vector = (u32)hc->ingpa;
+ send_ipi_ex.vp_set.format = hc->outgpa;
+ send_ipi_ex.vp_set.valid_bank_mask = sse128_lo(hc->xmm[0]);
+ }
trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
send_ipi_ex.vp_set.format,
@@ -1920,8 +1927,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
vector = send_ipi_ex.vector;
valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
- sparse_banks_len = bitmap_weight(&valid_bank_mask, 64) *
- sizeof(sparse_banks[0]);
+ sparse_banks_len = bitmap_weight(&valid_bank_mask, 64);
all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
@@ -1931,12 +1937,27 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
if (!sparse_banks_len)
goto ret_success;
- if (kvm_read_guest(kvm,
- hc->ingpa + offsetof(struct hv_send_ipi_ex,
- vp_set.bank_contents),
- sparse_banks,
- sparse_banks_len))
- return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ if (!hc->fast) {
+ if (kvm_read_guest(kvm,
+ hc->ingpa + offsetof(struct hv_send_ipi_ex,
+ vp_set.bank_contents),
+ sparse_banks,
+ sparse_banks_len * sizeof(sparse_banks[0])))
+ return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ } else {
+ /*
+ * The lower half of XMM0 is already consumed, each XMM holds
+ * two sparse banks.
+ */
+ if (sparse_banks_len > (2 * HV_HYPERCALL_MAX_XMM_REGISTERS - 1))
+ return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ for (i = 0; i < sparse_banks_len; i++) {
+ if (i % 2)
+ sparse_banks[i] = sse128_lo(hc->xmm[(i + 1) / 2]);
+ else
+ sparse_banks[i] = sse128_hi(hc->xmm[i / 2]);
+ }
+ }
}
check_and_send_ipi:
@@ -2098,6 +2119,7 @@ static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
+ case HVCALL_SEND_IPI_EX:
return true;
}
@@ -2265,14 +2287,8 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
ret = kvm_hv_flush_tlb(vcpu, &hc);
break;
case HVCALL_SEND_IPI:
- if (unlikely(hc.rep)) {
- ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
- break;
- }
- ret = kvm_hv_send_ipi(vcpu, &hc);
- break;
case HVCALL_SEND_IPI_EX:
- if (unlikely(hc.fast || hc.rep)) {
+ if (unlikely(hc.rep)) {
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
--
2.35.1
^ permalink raw reply related [flat|nested] 20+ messages in thread
* Re: [PATCH 4/4] KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall
2022-02-22 15:46 ` [PATCH 4/4] KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall Vitaly Kuznetsov
@ 2022-02-25 18:33 ` Maxim Levitsky
2022-02-28 10:02 ` Vitaly Kuznetsov
2022-02-28 10:48 ` Siddharth Chandrasekaran
1 sibling, 1 reply; 20+ messages in thread
From: Maxim Levitsky @ 2022-02-25 18:33 UTC (permalink / raw)
To: Vitaly Kuznetsov, kvm, Paolo Bonzini
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel
On Tue, 2022-02-22 at 16:46 +0100, Vitaly Kuznetsov wrote:
> It has been proven on practice that at least Windows Server 2019 tries
> using HVCALL_SEND_IPI_EX in 'XMM fast' mode when it has more than 64 vCPUs
> and it needs to send an IPI to a vCPU > 63. Similarly to other XMM Fast
> hypercalls (HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}{,_EX}), this
> information is missing in TLFS as of 6.0b. Currently, KVM returns an error
> (HV_STATUS_INVALID_HYPERCALL_INPUT) and Windows crashes.
>
> Note, HVCALL_SEND_IPI is a 'standard' fast hypercall (not 'XMM fast') as
> all its parameters fit into RDX:R8 and this is handled by KVM correctly.
>
> Fixes: d8f5537a8816 ("KVM: hyper-v: Advertise support for fast XMM hypercalls")
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
> ---
> arch/x86/kvm/hyperv.c | 52 ++++++++++++++++++++++++++++---------------
> 1 file changed, 34 insertions(+), 18 deletions(-)
>
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index 6dda93bf98ae..3060057bdfd4 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -1890,6 +1890,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
> int sparse_banks_len;
> u32 vector;
> bool all_cpus;
> + int i;
>
> if (hc->code == HVCALL_SEND_IPI) {
> if (!hc->fast) {
> @@ -1910,9 +1911,15 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
>
> trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
> } else {
> - if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
> - sizeof(send_ipi_ex))))
> - return HV_STATUS_INVALID_HYPERCALL_INPUT;
> + if (!hc->fast) {
> + if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
> + sizeof(send_ipi_ex))))
> + return HV_STATUS_INVALID_HYPERCALL_INPUT;
> + } else {
> + send_ipi_ex.vector = (u32)hc->ingpa;
> + send_ipi_ex.vp_set.format = hc->outgpa;
> + send_ipi_ex.vp_set.valid_bank_mask = sse128_lo(hc->xmm[0]);
> + }
>
> trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
> send_ipi_ex.vp_set.format,
> @@ -1920,8 +1927,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
>
> vector = send_ipi_ex.vector;
> valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
> - sparse_banks_len = bitmap_weight(&valid_bank_mask, 64) *
> - sizeof(sparse_banks[0]);
> + sparse_banks_len = bitmap_weight(&valid_bank_mask, 64);
Is this change intentional?
I haven't fully reviewed this, because kvm/queue seem to have a bit different
version of this, and I didn't fully follow on all of this.
Best regards,
Maxim Levitsky
>
> all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
>
> @@ -1931,12 +1937,27 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
> if (!sparse_banks_len)
> goto ret_success;
>
> - if (kvm_read_guest(kvm,
> - hc->ingpa + offsetof(struct hv_send_ipi_ex,
> - vp_set.bank_contents),
> - sparse_banks,
> - sparse_banks_len))
> - return HV_STATUS_INVALID_HYPERCALL_INPUT;
> + if (!hc->fast) {
> + if (kvm_read_guest(kvm,
> + hc->ingpa + offsetof(struct hv_send_ipi_ex,
> + vp_set.bank_contents),
> + sparse_banks,
> + sparse_banks_len * sizeof(sparse_banks[0])))
> + return HV_STATUS_INVALID_HYPERCALL_INPUT;
> + } else {
> + /*
> + * The lower half of XMM0 is already consumed, each XMM holds
> + * two sparse banks.
> + */
> + if (sparse_banks_len > (2 * HV_HYPERCALL_MAX_XMM_REGISTERS - 1))
> + return HV_STATUS_INVALID_HYPERCALL_INPUT;
> + for (i = 0; i < sparse_banks_len; i++) {
> + if (i % 2)
> + sparse_banks[i] = sse128_lo(hc->xmm[(i + 1) / 2]);
> + else
> + sparse_banks[i] = sse128_hi(hc->xmm[i / 2]);
> + }
> + }
> }
>
> check_and_send_ipi:
> @@ -2098,6 +2119,7 @@ static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
> + case HVCALL_SEND_IPI_EX:
> return true;
> }
>
> @@ -2265,14 +2287,8 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
> ret = kvm_hv_flush_tlb(vcpu, &hc);
> break;
> case HVCALL_SEND_IPI:
> - if (unlikely(hc.rep)) {
> - ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> - break;
> - }
> - ret = kvm_hv_send_ipi(vcpu, &hc);
> - break;
> case HVCALL_SEND_IPI_EX:
> - if (unlikely(hc.fast || hc.rep)) {
> + if (unlikely(hc.rep)) {
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH 4/4] KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall
2022-02-25 18:33 ` Maxim Levitsky
@ 2022-02-28 10:02 ` Vitaly Kuznetsov
0 siblings, 0 replies; 20+ messages in thread
From: Vitaly Kuznetsov @ 2022-02-28 10:02 UTC (permalink / raw)
To: Maxim Levitsky
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel, kvm, Paolo Bonzini
Maxim Levitsky <mlevitsk@redhat.com> writes:
> On Tue, 2022-02-22 at 16:46 +0100, Vitaly Kuznetsov wrote:
>> It has been proven on practice that at least Windows Server 2019 tries
>> using HVCALL_SEND_IPI_EX in 'XMM fast' mode when it has more than 64 vCPUs
>> and it needs to send an IPI to a vCPU > 63. Similarly to other XMM Fast
>> hypercalls (HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}{,_EX}), this
>> information is missing in TLFS as of 6.0b. Currently, KVM returns an error
>> (HV_STATUS_INVALID_HYPERCALL_INPUT) and Windows crashes.
>>
>> Note, HVCALL_SEND_IPI is a 'standard' fast hypercall (not 'XMM fast') as
>> all its parameters fit into RDX:R8 and this is handled by KVM correctly.
>>
>> Fixes: d8f5537a8816 ("KVM: hyper-v: Advertise support for fast XMM hypercalls")
>> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
>> ---
>> arch/x86/kvm/hyperv.c | 52 ++++++++++++++++++++++++++++---------------
>> 1 file changed, 34 insertions(+), 18 deletions(-)
>>
>> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
>> index 6dda93bf98ae..3060057bdfd4 100644
>> --- a/arch/x86/kvm/hyperv.c
>> +++ b/arch/x86/kvm/hyperv.c
>> @@ -1890,6 +1890,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
>> int sparse_banks_len;
>> u32 vector;
>> bool all_cpus;
>> + int i;
>>
>> if (hc->code == HVCALL_SEND_IPI) {
>> if (!hc->fast) {
>> @@ -1910,9 +1911,15 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
>>
>> trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
>> } else {
>> - if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
>> - sizeof(send_ipi_ex))))
>> - return HV_STATUS_INVALID_HYPERCALL_INPUT;
>> + if (!hc->fast) {
>> + if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
>> + sizeof(send_ipi_ex))))
>> + return HV_STATUS_INVALID_HYPERCALL_INPUT;
>> + } else {
>> + send_ipi_ex.vector = (u32)hc->ingpa;
>> + send_ipi_ex.vp_set.format = hc->outgpa;
>> + send_ipi_ex.vp_set.valid_bank_mask = sse128_lo(hc->xmm[0]);
>> + }
>>
>> trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
>> send_ipi_ex.vp_set.format,
>> @@ -1920,8 +1927,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
>>
>> vector = send_ipi_ex.vector;
>> valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
>> - sparse_banks_len = bitmap_weight(&valid_bank_mask, 64) *
>> - sizeof(sparse_banks[0]);
>> + sparse_banks_len = bitmap_weight(&valid_bank_mask, 64);
> Is this change intentional?
>
Yes it is. Previously, 'sparse_banks_len' was the number of bytes to
read, now it's in u64-s.
(see below)
> I haven't fully reviewed this, because kvm/queue seem to have a bit different
> version of this, and I didn't fully follow on all of this.
>
>>
>> all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
>>
>> @@ -1931,12 +1937,27 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
>> if (!sparse_banks_len)
>> goto ret_success;
>>
>> - if (kvm_read_guest(kvm,
>> - hc->ingpa + offsetof(struct hv_send_ipi_ex,
>> - vp_set.bank_contents),
>> - sparse_banks,
>> - sparse_banks_len))
>> - return HV_STATUS_INVALID_HYPERCALL_INPUT;
>> + if (!hc->fast) {
>> + if (kvm_read_guest(kvm,
>> + hc->ingpa + offsetof(struct hv_send_ipi_ex,
>> + vp_set.bank_contents),
>> + sparse_banks,
>> + sparse_banks_len * sizeof(sparse_banks[0])))
^^^ here ^^^
>> + return HV_STATUS_INVALID_HYPERCALL_INPUT;
>> + } else {
>> + /*
>> + * The lower half of XMM0 is already consumed, each XMM holds
>> + * two sparse banks.
>> + */
>> + if (sparse_banks_len > (2 * HV_HYPERCALL_MAX_XMM_REGISTERS - 1))
>> + return HV_STATUS_INVALID_HYPERCALL_INPUT;
And here. This is the reason for change: it's more convenient to count
it 'xmm halves' than in bytes.
>> + for (i = 0; i < sparse_banks_len; i++) {
>> + if (i % 2)
>> + sparse_banks[i] = sse128_lo(hc->xmm[(i + 1) / 2]);
>> + else
>> + sparse_banks[i] = sse128_hi(hc->xmm[i / 2]);
>> + }
>> + }
>> }
>>
>> check_and_send_ipi:
>> @@ -2098,6 +2119,7 @@ static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
>> case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
>> case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
>> case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
>> + case HVCALL_SEND_IPI_EX:
>> return true;
>> }
>>
>> @@ -2265,14 +2287,8 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
>> ret = kvm_hv_flush_tlb(vcpu, &hc);
>> break;
>> case HVCALL_SEND_IPI:
>> - if (unlikely(hc.rep)) {
>> - ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
>> - break;
>> - }
>> - ret = kvm_hv_send_ipi(vcpu, &hc);
>> - break;
>> case HVCALL_SEND_IPI_EX:
>> - if (unlikely(hc.fast || hc.rep)) {
>> + if (unlikely(hc.rep)) {
>> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
>> break;
>> }
>
>
--
Vitaly
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH 4/4] KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall
2022-02-22 15:46 ` [PATCH 4/4] KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall Vitaly Kuznetsov
2022-02-25 18:33 ` Maxim Levitsky
@ 2022-02-28 10:48 ` Siddharth Chandrasekaran
1 sibling, 0 replies; 20+ messages in thread
From: Siddharth Chandrasekaran @ 2022-02-28 10:48 UTC (permalink / raw)
To: Vitaly Kuznetsov
Cc: kvm, Paolo Bonzini, Sean Christopherson, Wanpeng Li, Jim Mattson,
linux-kernel
On Tue, Feb 22, 2022 at 04:46:42PM +0100, Vitaly Kuznetsov wrote:
> CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.
>
>
>
> It has been proven on practice that at least Windows Server 2019 tries
> using HVCALL_SEND_IPI_EX in 'XMM fast' mode when it has more than 64 vCPUs
> and it needs to send an IPI to a vCPU > 63. Similarly to other XMM Fast
> hypercalls (HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}{,_EX}), this
> information is missing in TLFS as of 6.0b. Currently, KVM returns an error
> (HV_STATUS_INVALID_HYPERCALL_INPUT) and Windows crashes.
>
> Note, HVCALL_SEND_IPI is a 'standard' fast hypercall (not 'XMM fast') as
> all its parameters fit into RDX:R8 and this is handled by KVM correctly.
>
> Fixes: d8f5537a8816 ("KVM: hyper-v: Advertise support for fast XMM hypercalls")
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Siddharth Chandrasekaran <sidcha@amazon.de>
Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Sitz: Berlin
Ust-ID: DE 289 237 879
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes
2022-02-22 15:46 [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes Vitaly Kuznetsov
` (3 preceding siblings ...)
2022-02-22 15:46 ` [PATCH 4/4] KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall Vitaly Kuznetsov
@ 2022-02-25 11:55 ` Paolo Bonzini
2022-02-25 13:13 ` Vitaly Kuznetsov
4 siblings, 1 reply; 20+ messages in thread
From: Paolo Bonzini @ 2022-02-25 11:55 UTC (permalink / raw)
To: Vitaly Kuznetsov, kvm
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel
On 2/22/22 16:46, Vitaly Kuznetsov wrote:
> While working on some Hyper-V TLB flush improvements and Direct TLB flush
> feature for Hyper-V on KVM I experienced Windows Server 2019 crashes on
> boot when XMM fast hypercall input feature is advertised. Turns out,
> HVCALL_SEND_IPI_EX is also an XMM fast hypercall and returning an error
> kills the guest. This is fixed in PATCH4. PATCH3 fixes erroneous capping
> of sparse CPU banks for XMM fast TLB flush hypercalls. The problem should
> be reproducible with >360 vCPUs.
>
> Vitaly Kuznetsov (4):
> KVM: x86: hyper-v: Drop redundant 'ex' parameter from
> kvm_hv_send_ipi()
> KVM: x86: hyper-v: Drop redundant 'ex' parameter from
> kvm_hv_flush_tlb()
> KVM: x86: hyper-v: Fix the maximum number of sparse banks for XMM fast
> TLB flush hypercalls
> KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall
>
> arch/x86/kvm/hyperv.c | 84 +++++++++++++++++++++++--------------------
> 1 file changed, 45 insertions(+), 39 deletions(-)
>
Merging this in 5.18 is a bit messy. Please check that the below
patch against kvm/next makes sense:
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 653e08c993c4..98fb998c31ce 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1770,9 +1770,11 @@ struct kvm_hv_hcall {
};
static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
+ int consumed_xmm_halves,
u64 *sparse_banks, gpa_t offset)
{
u16 var_cnt;
+ int i;
if (hc->var_cnt > 64)
return -EINVAL;
@@ -1780,13 +1782,29 @@ static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
/* Ignore banks that cannot possibly contain a legal VP index. */
var_cnt = min_t(u16, hc->var_cnt, KVM_HV_MAX_SPARSE_VCPU_SET_BITS);
+ if (hc->fast) {
+ /*
+ * Each XMM holds two sparse banks, but do not count halves that
+ * have already been consumed for hypercall parameters.
+ */
+ if (hc->var_cnt > 2 * HV_HYPERCALL_MAX_XMM_REGISTERS - consumed_xmm_halves)
+ return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ for (i = 0; i < var_cnt; i++) {
+ int j = i + consumed_xmm_halves;
+ if (j % 2)
+ sparse_banks[i] = sse128_lo(hc->xmm[j / 2]);
+ else
+ sparse_banks[i] = sse128_hi(hc->xmm[j / 2]);
+ }
+ return 0;
+ }
+
return kvm_read_guest(kvm, hc->ingpa + offset, sparse_banks,
var_cnt * sizeof(*sparse_banks));
}
-static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
+static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
{
- int i;
struct kvm *kvm = vcpu->kvm;
struct hv_tlb_flush_ex flush_ex;
struct hv_tlb_flush flush;
@@ -1803,7 +1821,8 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
*/
BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);
- if (!ex) {
+ if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
+ hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
if (hc->fast) {
flush.address_space = hc->ingpa;
flush.flags = hc->outgpa;
@@ -1859,17 +1878,7 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
if (!hc->var_cnt)
goto ret_success;
- if (hc->fast) {
- if (hc->var_cnt > HV_HYPERCALL_MAX_XMM_REGISTERS - 1)
- return HV_STATUS_INVALID_HYPERCALL_INPUT;
- for (i = 0; i < hc->var_cnt; i += 2) {
- sparse_banks[i] = sse128_lo(hc->xmm[i / 2 + 1]);
- sparse_banks[i + 1] = sse128_hi(hc->xmm[i / 2 + 1]);
- }
- goto do_flush;
- }
-
- if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks,
+ if (kvm_get_sparse_vp_set(kvm, hc, 2, sparse_banks,
offsetof(struct hv_tlb_flush_ex,
hv_vp_set.bank_contents)))
return HV_STATUS_INVALID_HYPERCALL_INPUT;
@@ -1913,7 +1922,7 @@ static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
}
}
-static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
+static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
{
struct kvm *kvm = vcpu->kvm;
struct hv_send_ipi_ex send_ipi_ex;
@@ -1924,7 +1933,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
u32 vector;
bool all_cpus;
- if (!ex) {
+ if (hc->code == HVCALL_SEND_IPI) {
if (!hc->fast) {
if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
sizeof(send_ipi))))
@@ -1943,9 +1952,15 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
} else {
- if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
- sizeof(send_ipi_ex))))
- return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ if (!hc->fast) {
+ if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
+ sizeof(send_ipi_ex))))
+ return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ } else {
+ send_ipi_ex.vector = (u32)hc->ingpa;
+ send_ipi_ex.vp_set.format = hc->outgpa;
+ send_ipi_ex.vp_set.valid_bank_mask = sse128_lo(hc->xmm[0]);
+ }
trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
send_ipi_ex.vp_set.format,
@@ -1964,7 +1979,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
if (!hc->var_cnt)
goto ret_success;
- if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks,
+ if (kvm_get_sparse_vp_set(kvm, hc, 1, sparse_banks,
offsetof(struct hv_send_ipi_ex,
vp_set.bank_contents)))
return HV_STATUS_INVALID_HYPERCALL_INPUT;
@@ -2126,6 +2141,7 @@ static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
+ case HVCALL_SEND_IPI_EX:
return true;
}
@@ -2283,46 +2299,43 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
kvm_hv_hypercall_complete_userspace;
return 0;
case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
- if (unlikely(!hc.rep_cnt || hc.rep_idx || hc.var_cnt)) {
+ if (unlikely(hc.var_cnt)) {
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
- ret = kvm_hv_flush_tlb(vcpu, &hc, false);
- break;
- case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
- if (unlikely(hc.rep || hc.var_cnt)) {
- ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
- break;
- }
- ret = kvm_hv_flush_tlb(vcpu, &hc, false);
- break;
+ fallthrough;
case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
- ret = kvm_hv_flush_tlb(vcpu, &hc, true);
+ ret = kvm_hv_flush_tlb(vcpu, &hc);
break;
+ case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
+ if (unlikely(hc.var_cnt)) {
+ ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
+ break;
+ }
+ fallthrough;
case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
if (unlikely(hc.rep)) {
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
- ret = kvm_hv_flush_tlb(vcpu, &hc, true);
+ ret = kvm_hv_flush_tlb(vcpu, &hc);
break;
case HVCALL_SEND_IPI:
- if (unlikely(hc.rep || hc.var_cnt)) {
+ if (unlikely(hc.var_cnt)) {
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
- ret = kvm_hv_send_ipi(vcpu, &hc, false);
- break;
+ fallthrough;
case HVCALL_SEND_IPI_EX:
- if (unlikely(hc.fast || hc.rep)) {
+ if (unlikely(hc.rep)) {
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
- ret = kvm_hv_send_ipi(vcpu, &hc, true);
+ ret = kvm_hv_send_ipi(vcpu, &hc);
break;
case HVCALL_POST_DEBUG_DATA:
case HVCALL_RETRIEVE_DEBUG_DATA:
The resulting merge commit is already in kvm/queue shortly (which should
become the next kvm/next as soon as tests complete).
Paolo
^ permalink raw reply related [flat|nested] 20+ messages in thread
* Re: [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes
2022-02-25 11:55 ` [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes Paolo Bonzini
@ 2022-02-25 13:13 ` Vitaly Kuznetsov
2022-02-25 13:17 ` Paolo Bonzini
0 siblings, 1 reply; 20+ messages in thread
From: Vitaly Kuznetsov @ 2022-02-25 13:13 UTC (permalink / raw)
To: Paolo Bonzini, kvm
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel
Paolo Bonzini <pbonzini@redhat.com> writes:
> On 2/22/22 16:46, Vitaly Kuznetsov wrote:
>> While working on some Hyper-V TLB flush improvements and Direct TLB flush
>> feature for Hyper-V on KVM I experienced Windows Server 2019 crashes on
>> boot when XMM fast hypercall input feature is advertised. Turns out,
>> HVCALL_SEND_IPI_EX is also an XMM fast hypercall and returning an error
>> kills the guest. This is fixed in PATCH4. PATCH3 fixes erroneous capping
>> of sparse CPU banks for XMM fast TLB flush hypercalls. The problem should
>> be reproducible with >360 vCPUs.
>>
>> Vitaly Kuznetsov (4):
>> KVM: x86: hyper-v: Drop redundant 'ex' parameter from
>> kvm_hv_send_ipi()
>> KVM: x86: hyper-v: Drop redundant 'ex' parameter from
>> kvm_hv_flush_tlb()
>> KVM: x86: hyper-v: Fix the maximum number of sparse banks for XMM fast
>> TLB flush hypercalls
>> KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall
>>
>> arch/x86/kvm/hyperv.c | 84 +++++++++++++++++++++++--------------------
>> 1 file changed, 45 insertions(+), 39 deletions(-)
>>
>
> Merging this in 5.18 is a bit messy. Please check that the below
> patch against kvm/next makes sense:
Something is wrong with the diff as it doesn't apply :-(
>
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index 653e08c993c4..98fb998c31ce 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -1770,9 +1770,11 @@ struct kvm_hv_hcall {
> };
>
> static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
> + int consumed_xmm_halves,
> u64 *sparse_banks, gpa_t offset)
> {
> u16 var_cnt;
> + int i;
>
> if (hc->var_cnt > 64)
> return -EINVAL;
> @@ -1780,13 +1782,29 @@ static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
> /* Ignore banks that cannot possibly contain a legal VP index. */
> var_cnt = min_t(u16, hc->var_cnt, KVM_HV_MAX_SPARSE_VCPU_SET_BITS);
>
> + if (hc->fast) {
> + /*
> + * Each XMM holds two sparse banks, but do not count halves that
> + * have already been consumed for hypercall parameters.
> + */
> + if (hc->var_cnt > 2 * HV_HYPERCALL_MAX_XMM_REGISTERS - consumed_xmm_halves)
> + return HV_STATUS_INVALID_HYPERCALL_INPUT;
> + for (i = 0; i < var_cnt; i++) {
> + int j = i + consumed_xmm_halves;
> + if (j % 2)
> + sparse_banks[i] = sse128_lo(hc->xmm[j / 2]);
> + else
> + sparse_banks[i] = sse128_hi(hc->xmm[j / 2]);
Let's say we have 1 half of XMM0 consumed. Now:
i = 0;
j = 1;
if (1)
sparse_banks[0] = sse128_lo(hc->xmm[0]);
This doesn't look right as we need to get the upper half of XMM0.
I guess it should be reversed,
if (j % 2)
sparse_banks[i] = sse128_hi(hc->xmm[j / 2]);
else
sparse_banks[i] = sse128_lo(hc->xmm[j / 2]);
> + }
> + return 0;
> + }
> +
> return kvm_read_guest(kvm, hc->ingpa + offset, sparse_banks,
> var_cnt * sizeof(*sparse_banks));
> }
>
> -static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
> +static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
> {
> - int i;
> struct kvm *kvm = vcpu->kvm;
> struct hv_tlb_flush_ex flush_ex;
> struct hv_tlb_flush flush;
> @@ -1803,7 +1821,8 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
> */
> BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);
>
> - if (!ex) {
> + if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
> + hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
In case you're trying to come up with a smaller patch for 5.18, we can
certainly drop these 'ex'/'non-ex' changes as these are merely
cosmetic.
> if (hc->fast) {
> flush.address_space = hc->ingpa;
> flush.flags = hc->outgpa;
> @@ -1859,17 +1878,7 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
> if (!hc->var_cnt)
> goto ret_success;
>
> - if (hc->fast) {
> - if (hc->var_cnt > HV_HYPERCALL_MAX_XMM_REGISTERS - 1)
> - return HV_STATUS_INVALID_HYPERCALL_INPUT;
> - for (i = 0; i < hc->var_cnt; i += 2) {
> - sparse_banks[i] = sse128_lo(hc->xmm[i / 2 + 1]);
> - sparse_banks[i + 1] = sse128_hi(hc->xmm[i / 2 + 1]);
> - }
> - goto do_flush;
> - }
> -
> - if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks,
> + if (kvm_get_sparse_vp_set(kvm, hc, 2, sparse_banks,
> offsetof(struct hv_tlb_flush_ex,
> hv_vp_set.bank_contents)))
I like your idea to put 'consumed_xmm_halves' into
kvm_get_sparse_vp_set() as kvm_hv_flush_tlb is getting too big.
> return HV_STATUS_INVALID_HYPERCALL_INPUT;
> @@ -1913,7 +1922,7 @@ static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
> }
> }
>
> -static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
> +static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
> {
> struct kvm *kvm = vcpu->kvm;
> struct hv_send_ipi_ex send_ipi_ex;
> @@ -1924,7 +1933,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
> u32 vector;
> bool all_cpus;
>
> - if (!ex) {
> + if (hc->code == HVCALL_SEND_IPI) {
> if (!hc->fast) {
> if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
> sizeof(send_ipi))))
> @@ -1943,9 +1952,15 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
>
> trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
> } else {
> - if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
> - sizeof(send_ipi_ex))))
> - return HV_STATUS_INVALID_HYPERCALL_INPUT;
> + if (!hc->fast) {
> + if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
> + sizeof(send_ipi_ex))))
> + return HV_STATUS_INVALID_HYPERCALL_INPUT;
> + } else {
> + send_ipi_ex.vector = (u32)hc->ingpa;
> + send_ipi_ex.vp_set.format = hc->outgpa;
> + send_ipi_ex.vp_set.valid_bank_mask = sse128_lo(hc->xmm[0]);
> + }
>
> trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
> send_ipi_ex.vp_set.format,
> @@ -1964,7 +1979,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
> if (!hc->var_cnt)
> goto ret_success;
>
> - if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks,
> + if (kvm_get_sparse_vp_set(kvm, hc, 1, sparse_banks,
> offsetof(struct hv_send_ipi_ex,
> vp_set.bank_contents)))
> return HV_STATUS_INVALID_HYPERCALL_INPUT;
> @@ -2126,6 +2141,7 @@ static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
> + case HVCALL_SEND_IPI_EX:
> return true;
> }
>
> @@ -2283,46 +2299,43 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
> kvm_hv_hypercall_complete_userspace;
> return 0;
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
> - if (unlikely(!hc.rep_cnt || hc.rep_idx || hc.var_cnt)) {
> + if (unlikely(hc.var_cnt)) {
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
> - ret = kvm_hv_flush_tlb(vcpu, &hc, false);
> - break;
> - case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
> - if (unlikely(hc.rep || hc.var_cnt)) {
> - ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> - break;
> - }
> - ret = kvm_hv_flush_tlb(vcpu, &hc, false);
> - break;
> + fallthrough;
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
> if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
> - ret = kvm_hv_flush_tlb(vcpu, &hc, true);
> + ret = kvm_hv_flush_tlb(vcpu, &hc);
> break;
> + case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
> + if (unlikely(hc.var_cnt)) {
> + ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> + break;
> + }
> + fallthrough;
> case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
> if (unlikely(hc.rep)) {
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
> - ret = kvm_hv_flush_tlb(vcpu, &hc, true);
> + ret = kvm_hv_flush_tlb(vcpu, &hc);
> break;
> case HVCALL_SEND_IPI:
> - if (unlikely(hc.rep || hc.var_cnt)) {
> + if (unlikely(hc.var_cnt)) {
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
> - ret = kvm_hv_send_ipi(vcpu, &hc, false);
> - break;
> + fallthrough;
> case HVCALL_SEND_IPI_EX:
> - if (unlikely(hc.fast || hc.rep)) {
> + if (unlikely(hc.rep)) {
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
> - ret = kvm_hv_send_ipi(vcpu, &hc, true);
> + ret = kvm_hv_send_ipi(vcpu, &hc);
> break;
> case HVCALL_POST_DEBUG_DATA:
> case HVCALL_RETRIEVE_DEBUG_DATA:
I've smoke tested this (with the change I've mentioned above) and WS2019
booted with 65 vCPUs. This is a good sign)
>
>
> The resulting merge commit is already in kvm/queue shortly (which should
> become the next kvm/next as soon as tests complete).
>
I see, please swap sse128_lo()/sse128_hi() there too :-)
--
Vitaly
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes
2022-02-25 13:13 ` Vitaly Kuznetsov
@ 2022-02-25 13:17 ` Paolo Bonzini
2022-02-28 10:52 ` Siddharth Chandrasekaran
0 siblings, 1 reply; 20+ messages in thread
From: Paolo Bonzini @ 2022-02-25 13:17 UTC (permalink / raw)
To: Vitaly Kuznetsov, kvm
Cc: Sean Christopherson, Wanpeng Li, Jim Mattson,
Siddharth Chandrasekaran, linux-kernel
On 2/25/22 14:13, Vitaly Kuznetsov wrote:
> Let's say we have 1 half of XMM0 consumed. Now:
>
> i = 0;
> j = 1;
> if (1)
> sparse_banks[0] = sse128_lo(hc->xmm[0]);
>
> This doesn't look right as we need to get the upper half of XMM0.
>
> I guess it should be reversed,
>
> if (j % 2)
> sparse_banks[i] = sse128_hi(hc->xmm[j / 2]);
> else
> sparse_banks[i] = sse128_lo(hc->xmm[j / 2]);
Yeah, of course.
Thanks!
Paolo
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes
2022-02-25 13:17 ` Paolo Bonzini
@ 2022-02-28 10:52 ` Siddharth Chandrasekaran
2022-02-28 11:09 ` Vitaly Kuznetsov
0 siblings, 1 reply; 20+ messages in thread
From: Siddharth Chandrasekaran @ 2022-02-28 10:52 UTC (permalink / raw)
To: Paolo Bonzini
Cc: Vitaly Kuznetsov, kvm, Sean Christopherson, Wanpeng Li,
Jim Mattson, linux-kernel
On Fri, Feb 25, 2022 at 02:17:04PM +0100, Paolo Bonzini wrote:
> On 2/25/22 14:13, Vitaly Kuznetsov wrote:
> > Let's say we have 1 half of XMM0 consumed. Now:
> >
> > i = 0;
> > j = 1;
> > if (1)
> > sparse_banks[0] = sse128_lo(hc->xmm[0]);
> >
> > This doesn't look right as we need to get the upper half of XMM0.
> >
> > I guess it should be reversed,
> >
> > if (j % 2)
> > sparse_banks[i] = sse128_hi(hc->xmm[j / 2]);
> > else
> > sparse_banks[i] = sse128_lo(hc->xmm[j / 2]);
Maybe I am missing parts of this series.. I dont see this change in any
of the 4 patches Vitaly sent. Yes, they look swapped to me too.
~ Sid.
Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Sitz: Berlin
Ust-ID: DE 289 237 879
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes
2022-02-28 10:52 ` Siddharth Chandrasekaran
@ 2022-02-28 11:09 ` Vitaly Kuznetsov
2022-02-28 16:18 ` Siddharth Chandrasekaran
0 siblings, 1 reply; 20+ messages in thread
From: Vitaly Kuznetsov @ 2022-02-28 11:09 UTC (permalink / raw)
To: Siddharth Chandrasekaran
Cc: kvm, Sean Christopherson, Wanpeng Li, Jim Mattson, linux-kernel,
Paolo Bonzini
Siddharth Chandrasekaran <sidcha@amazon.de> writes:
> On Fri, Feb 25, 2022 at 02:17:04PM +0100, Paolo Bonzini wrote:
>> On 2/25/22 14:13, Vitaly Kuznetsov wrote:
>> > Let's say we have 1 half of XMM0 consumed. Now:
>> >
>> > i = 0;
>> > j = 1;
>> > if (1)
>> > sparse_banks[0] = sse128_lo(hc->xmm[0]);
>> >
>> > This doesn't look right as we need to get the upper half of XMM0.
>> >
>> > I guess it should be reversed,
>> >
>> > if (j % 2)
>> > sparse_banks[i] = sse128_hi(hc->xmm[j / 2]);
>> > else
>> > sparse_banks[i] = sse128_lo(hc->xmm[j / 2]);
>
> Maybe I am missing parts of this series.. I dont see this change in any
> of the 4 patches Vitaly sent. Yes, they look swapped to me too.
>
There was a conflict with a patch series from Sean:
https://lore.kernel.org/kvm/20211207220926.718794-1-seanjc@google.com/
and this is a part of the resolution:
commit c0f1eaeb9e628bf86bf50f11cb4a2b671528391e
Merge: 4dfc4ec2b7f5 47d3e5cdfe60
Author: Paolo Bonzini <pbonzini@redhat.com>
Date: Fri Feb 25 06:28:10 2022 -0500
Merge branch 'kvm-hv-xmm-hypercall-fixes' into HEAD
--
Vitaly
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH 0/4] KVM: x86: hyper-v: XMM fast hypercalls fixes
2022-02-28 11:09 ` Vitaly Kuznetsov
@ 2022-02-28 16:18 ` Siddharth Chandrasekaran
0 siblings, 0 replies; 20+ messages in thread
From: Siddharth Chandrasekaran @ 2022-02-28 16:18 UTC (permalink / raw)
To: Vitaly Kuznetsov
Cc: kvm, Sean Christopherson, Wanpeng Li, Jim Mattson, linux-kernel,
Paolo Bonzini
On Mon, Feb 28, 2022 at 12:09:14PM +0100, Vitaly Kuznetsov wrote:
> Siddharth Chandrasekaran <sidcha@amazon.de> writes:
> > On Fri, Feb 25, 2022 at 02:17:04PM +0100, Paolo Bonzini wrote:
> >> On 2/25/22 14:13, Vitaly Kuznetsov wrote:
> >> > Let's say we have 1 half of XMM0 consumed. Now:
> >> >
> >> > i = 0;
> >> > j = 1;
> >> > if (1)
> >> > sparse_banks[0] = sse128_lo(hc->xmm[0]);
> >> >
> >> > This doesn't look right as we need to get the upper half of XMM0.
> >> >
> >> > I guess it should be reversed,
> >> >
> >> > if (j % 2)
> >> > sparse_banks[i] = sse128_hi(hc->xmm[j / 2]);
> >> > else
> >> > sparse_banks[i] = sse128_lo(hc->xmm[j / 2]);
> >
> > Maybe I am missing parts of this series.. I dont see this change in any
> > of the 4 patches Vitaly sent. Yes, they look swapped to me too.
> >
>
> There was a conflict with a patch series from Sean:
> https://lore.kernel.org/kvm/20211207220926.718794-1-seanjc@google.com/
>
> and this is a part of the resolution:
>
> commit c0f1eaeb9e628bf86bf50f11cb4a2b671528391e
> Merge: 4dfc4ec2b7f5 47d3e5cdfe60
> Author: Paolo Bonzini <pbonzini@redhat.com>
> Date: Fri Feb 25 06:28:10 2022 -0500
>
> Merge branch 'kvm-hv-xmm-hypercall-fixes' into HEAD
Got it, thank you!
~ Sid.
Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Sitz: Berlin
Ust-ID: DE 289 237 879
^ permalink raw reply [flat|nested] 20+ messages in thread