KVM: SVM: Do all per-VM AVIC initialization during vCPU precreation phase

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Move all per-VM AVIC initialization from VM creation to vCPU pre-creation,
i.e. defer allocating the logical ID table and adding the VM to the GA Log
list until vCPUs are created.  This will allow removing the VM from the GA
Log list before vCPUs are destroyed without needing yet another kvm_x86_ops
hook (.vm_pre_destroy() is very intentionally called if and only if VM
creation fully succeeds).

As a bonus, this re-unites physical and logic table allocation, and avoids
allocating a logical table in the unlikely scenario that userspace creates
a VM without an in-kernel local APIC.

Another bonus to hooking .vcpu_precreate() is that there is no need to
unwind on failure, as the VM has already been created, i.e. KVM will run
through all phases of VM destruction.  In fact, unwinding is undesirable,
as KVM tries to keep VM-wide behavior idempotent/sticky across creaton of
multiple vCPUs.

Reviewed-by: Naveen N Rao (AMD) <naveen@kernel.org>
Link: https://patch.msgid.link/20260630210156.457151-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

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This commit is contained in:

Sean Christopherson 2026-06-30 14:01:55 -07:00

parent 8b47740b3a

commit 4fa9a3767d

3 changed files with 51 additions and 38 deletions

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94

arch/x86/kvm/svm/avic.c

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6

arch/x86/kvm/svm/svm.c

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1

arch/x86/kvm/svm/svm.h

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