Re: [PATCH] KVM: Deal with nested sleeps in kvm_vcpu_block()

From: Paolo Bonzini
Date: Fri Dec 02 2022 - 13:28:08 EST


On 12/2/22 16:52, Space Meyer wrote:
The bug doesn't seem to be easily reproducible, but looking at the
code this should also be applicable for the upstream 6.0, 5.15, 5.10,
5.4, 4.19 and 4.14 branches, which have not received a backport of
26844fe.

Do you think this is all we should do? My conclusion from the LWN
article was, that we should avoid the set_current_state ->
conditional -> schedule pattern when possible as well.

Yes, the bug is there but unfortunately the backport is not easy. I don't really feel confident backporting the fix to older kernels; even if it is apparently just a couple lines of code, event handling is very delicate and has had a lot of changes recently.

Paolo