>>> On 16.03.16 at 15:21, <paul.durr...@citrix.com> wrote: > Commit b38d426a "flush remote tlbs by hypercall" add support to allow > Windows to request flush of remote TLB via hypercall rather than IPI. > Unfortunately it seems that this code was broken in a couple of ways: > > 1) The allocation of the per-vcpu ipi mask is gated on whether the > domain has viridian features enabled but the call to allocate is > made before the toolstack has enabled those features. This results > in a NULL pointer dereference. > > 2) One of the flush hypercall variants is a rep op, but the code > does not update the output data with the reps completed. Hence the > guest will spin repeatedly making the hypercall because it believes > it has uncompleted reps. > > This patch fixes both of these issues as follows: > > 1) The ipi mask need only be per-pcpu so it is made a per-pcpu static > to avoid the need for allocation. > > 2) The rep complete count is updated to the rep count since the single > flush that Xen does covers all reps anyway. > > Signed-off-by: Paul Durrant <paul.durr...@citrix.com>
Reviewed-by: Jan Beulich <jbeul...@suse.com> _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
