| Message ID | 1453843860-29591-3-git-send-email-konrad.wilk@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jan 26, 2016 at 04:30:58PM -0500, Konrad Rzeszutek Wilk wrote: > To hopefully clarify what it meant. Also point out that mechanism > by which the return 1 value is done is via an intimate knowledge of the > hypercall ABI (i.e. which register - eax - is the return value). > > Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> As far as I can tell all concerns in previous versions have been addressed. Acked-by: Wei Liu <wei.liu2@citrix.com>
On Mon, 2016-02-01 at 12:14 +0000, Wei Liu wrote: > On Tue, Jan 26, 2016 at 04:30:58PM -0500, Konrad Rzeszutek Wilk wrote: > > To hopefully clarify what it meant. Also point out that mechanism > > by which the return 1 value is done is via an intimate knowledge of the > > hypercall ABI (i.e. which register - eax - is the return value). > > > > Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > > As far as I can tell all concerns in previous versions have been > addressed. > > Acked-by: Wei Liu <wei.liu2@citrix.com> Applied.
diff --git a/tools/libxc/xc_resume.c b/tools/libxc/xc_resume.c index 87d4324..e692b81 100644 --- a/tools/libxc/xc_resume.c +++ b/tools/libxc/xc_resume.c @@ -248,11 +248,20 @@ out: /* * Resume execution of a domain after suspend shutdown. * This can happen in one of two ways: - * 1. Resume with special return code. - * 2. Reset guest environment so it believes it is resumed in a new - * domain context. + * 1. (fast=1) Resume the guest without resetting the domain environment. + * The guests's call to SCHEDOP_shutdown(SHUTDOWN_suspend) will return 1. + * + * 2. (fast=0) Reset guest environment so it believes it is resumed in a new + * domain context. The guests's call to SCHEDOP_shutdown(SHUTDOWN_suspend) + * will return 0. + * + * (1) should only by used for guests which can handle the special return + * code. Also note that the insertion of the return code is quite interesting + * and that the guest MUST be paused - otherwise we would be corrupting + * the guest vCPU state. + * * (2) should be used only for guests which cannot handle the special - * new return code. (1) is always safe (but slower). + * new return code - and it is always safe (but slower). */ int xc_domain_resume(xc_interface *xch, uint32_t domid, int fast) {
To hopefully clarify what it meant. Also point out that mechanism by which the return 1 value is done is via an intimate knowledge of the hypercall ABI (i.e. which register - eax - is the return value). Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> --- tools/libxc/xc_resume.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-)