Re: [Xen-devel] [PATCH] tests/xen-access: disable CR4 write events on application exit

[Tamas K Lengyel <tamas@xxxxxxxxxxxxx>]

On Mon, Jan 29, 2018 at 10:10 AM, Razvan Cojocaru
<rcojocaru@xxxxxxxxxxxxxxx> wrote:
> On exit, xen-access did not unsubscribe from CR4 write vm_events,
> potentially leaving the guest stuck.
>
> Signed-off-by: Razvan Cojocaru <rcojocaru@xxxxxxxxxxxxxxx>
> ---
>  tools/tests/xen-access/xen-access.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/tools/tests/xen-access/xen-access.c 
> b/tools/tests/xen-access/xen-access.c
> index 9d960e2..c572550 100644
> --- a/tools/tests/xen-access/xen-access.c
> +++ b/tools/tests/xen-access/xen-access.c
> @@ -654,6 +654,8 @@ int main(int argc, char *argv[])
>                  rc = xc_monitor_cpuid(xch, domain_id, 0);
>              if ( desc_access )
>                  rc = xc_monitor_descriptor_access(xch, domain_id, 0);
> +            if ( write_ctrlreg_cr4 )
> +                rc = xc_monitor_write_ctrlreg(xch, domain_id, 
> VM_EVENT_X86_CR4, 0, 1, 0, 1);

Any reason for the sync and onchangeonly parts to be set to 1 here? I
don't think it has any effect when you are disabling an event.

Tamas

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel