On 3/29/23 17:17, Tudor Ambarus wrote:
From: Sean Christopherson<seanjc@xxxxxxxxxx> commit 98c25ead5eda5e9d41abe57839ad3e8caf19500c upstream. Handle the switch to/from the hypervisor/software timer when a vCPU is blocking in common x86 instead of in VMX. Even though VMX is the only user of a hypervisor timer, the logic and all functions involved are generic x86 (unless future CPUs do something completely different and implement a hypervisor timer that runs regardless of mode). Handling the switch in common x86 will allow for the elimination of the pre/post_blocks hooks, and also lets KVM switch back to the hypervisor timer if and only if it was in use (without additional params). Add a comment explaining why the switch cannot be deferred to kvm_sched_out() or kvm_vcpu_block(). Signed-off-by: Sean Christopherson<seanjc@xxxxxxxxxx> Reviewed-by: Maxim Levitsky<mlevitsk@xxxxxxxxxx> Message-Id:<20211208015236.1616697-8-seanjc@xxxxxxxxxx> Signed-off-by: Paolo Bonzini<pbonzini@xxxxxxxxxx> [ta: Fix conflicts in vmx_pre_block and vmx_post_block as per Paolo's suggestion. Add Reported-by and Link tags.] Reported-by:syzbot+b6a74be92b5063a0f1ff@xxxxxxxxxxxxxxxxxxxxxxxxx Link:https://syzkaller.appspot.com/bug?id=489beb3d76ef14cc6cd18125782dc6f86051a605 Tested-by: Tudor Ambarus<tudor.ambarus@xxxxxxxxxx> Signed-off-by: Tudor Ambarus<tudor.ambarus@xxxxxxxxxx>
Acked-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>