[xen stable-4.9] sync CPU state upon final domain destruction
Author: Jan Beulich <[hidden email]>
AuthorDate: Wed Dec 20 15:51:47 2017 +0100
Commit: Jan Beulich <[hidden email]>
CommitDate: Wed Dec 20 15:51:47 2017 +0100
sync CPU state upon final domain destruction
See the code comment being added for why we need this.
This is being placed here to balance between the desire to prevent
future similar issues (the risk of which would grow if it was put
further down the call stack, e.g. in vmx_vcpu_destroy()) and the
intention to limit the performance impact (otherwise it could also go
into rcu_do_batch(), paralleling the use in do_tasklet_work()).
Reported-by: Igor Druzhinin <[hidden email]>
Signed-off-by: Jan Beulich <[hidden email]>
Acked-by: Andrew Cooper <[hidden email]>
master commit: 24246e1fb7496b830aca8a6a1fd3064ca1e3ebf9
master date: 2017-11-23 11:38:22 +0100
xen/common/domain.c | 8 ++++++++
1 file changed, 8 insertions(+)
+ * Flush all state for the vCPU previously having run on the current CPU.
+ * This is in particular relevant for x86 HVM ones on VMX, so that this
+ * flushing of state won't happen from the TLB flush IPI handler behind
+ * the back of a vmx_vmcs_enter() / vmx_vmcs_exit() section.
for ( i = d->max_vcpus - 1; i >= 0; i-- )
if ( (v = d->vcpu[i]) == NULL )
generated by git-patchbot for /home/xen/git/xen.git#stable-4.9