x86/kvm: Alloc dummy async #PF token outside of raw spinlock

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Drop the raw spinlock in kvm_async_pf_task_wake() before allocating the
the dummy async #PF token, the allocator is preemptible on PREEMPT_RT
kernels and must not be called from truly atomic contexts.

Opportunistically document why it's ok to loop on allocation failure,
i.e. why the function won't get stuck in an infinite loop.

Reported-by: Yajun Deng <yajun.deng@linux.dev>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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Sean Christopherson 2022-05-19 07:57:11 -07:00 • committed by Paolo Bonzini

parent fee060cd52

commit 0547758a6d

1 changed files with 27 additions and 14 deletions

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arch/x86/kernel/kvm.c

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