Re: [Xen-devel] [PATCH] VMX: use non-atomic bitops to manage MSR state

2016-06-23 Thread Tian, Kevin
> From: Jan Beulich [mailto:jbeul...@suse.com] > Sent: Monday, June 20, 2016 7:31 PM > > All host_msr_state accesses are solely on the owning CPU, and all > guest_msr_state ones solely when the vCPU is current or being switched > to. This, btw, is also in line with the use of find_first_set_bit()

Re: [Xen-devel] [PATCH] VMX: use non-atomic bitops to manage MSR state

2016-06-20 Thread Andrew Cooper
On 20/06/16 12:31, Jan Beulich wrote: > All host_msr_state accesses are solely on the owning CPU, and all > guest_msr_state ones solely when the vCPU is current or being switched > to. This, btw, is also in line with the use of find_first_set_bit() > (which would be bogus if ->flags could get updat

[Xen-devel] [PATCH] VMX: use non-atomic bitops to manage MSR state

2016-06-20 Thread Jan Beulich
All host_msr_state accesses are solely on the owning CPU, and all guest_msr_state ones solely when the vCPU is current or being switched to. This, btw, is also in line with the use of find_first_set_bit() (which would be bogus if ->flags could get updated behind its back). Signed-off-by: Jan Beuli