This is a note to let you know that I've just added the patch titled
KVM: x86: hyper-v: Avoid calling kvm_make_vcpus_request_mask() with vcpu_mask==NULL
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-x86-hyper-v-avoid-calling-kvm_make_vcpus_request_mask-with-vcpu_mask-null.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 6470accc7ba948b0b3aca22b273fe84ec638a116 Mon Sep 17 00:00:00 2001
From: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Date: Fri, 3 Sep 2021 09:51:36 +0200
Subject: KVM: x86: hyper-v: Avoid calling kvm_make_vcpus_request_mask() with vcpu_mask==NULL
From: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
commit 6470accc7ba948b0b3aca22b273fe84ec638a116 upstream.
In preparation to making kvm_make_vcpus_request_mask() use for_each_set_bit()
switch kvm_hv_flush_tlb() to calling kvm_make_all_cpus_request() for 'all cpus'
case.
Note: kvm_make_all_cpus_request() (unlike kvm_make_vcpus_request_mask())
currently dynamically allocates cpumask on each call and this is suboptimal.
Both kvm_make_all_cpus_request() and kvm_make_vcpus_request_mask() are
going to be switched to using pre-allocated per-cpu masks.
Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Message-Id: <20210903075141.403071-4-vkuznets@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Acked-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Fixes: 6100066358ee ("KVM: Optimize kvm_make_vcpus_request_mask() a bit")
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kvm/hyperv.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1562,16 +1562,19 @@ static u64 kvm_hv_flush_tlb(struct kvm_v
cpumask_clear(&hv_vcpu->tlb_flush);
- vcpu_mask = all_cpus ? NULL :
- sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask,
- vp_bitmap, vcpu_bitmap);
-
/*
* vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
* analyze it here, flush TLB regardless of the specified address space.
*/
- kvm_make_vcpus_request_mask(kvm, KVM_REQ_TLB_FLUSH_GUEST,
- NULL, vcpu_mask, &hv_vcpu->tlb_flush);
+ if (all_cpus) {
+ kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH_GUEST);
+ } else {
+ vcpu_mask = sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask,
+ vp_bitmap, vcpu_bitmap);
+
+ kvm_make_vcpus_request_mask(kvm, KVM_REQ_TLB_FLUSH_GUEST,
+ NULL, vcpu_mask, &hv_vcpu->tlb_flush);
+ }
ret_success:
/* We always do full TLB flush, set rep_done = rep_cnt. */
Patches currently in stable-queue which might be from vkuznets@xxxxxxxxxx are
queue-5.10/kvm-x86-hyper-v-avoid-calling-kvm_make_vcpus_request_mask-with-vcpu_mask-null.patch
