When starting a guest via libvirt (`virsh start --console`), early
console output was missed because the guest was started first and then
the console was attached. This patch changes this to the following
sequence:
1. create a paused guest
2. attach the console
3. resume the guest
Reviewed-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
---
tools/virsh-domain.c | 50 +++++++++++++++++++++++++++++++-------------
1 file changed, 35 insertions(+), 15 deletions(-)
diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
index 5c3c6d18aebf..36670039444c 100644
--- a/tools/virsh-domain.c
+++ b/tools/virsh-domain.c
@@ -4059,12 +4059,27 @@ static const vshCmdOptDef opts_start[] = {
{.name = NULL}
};
+static int
+virDomainCreateHelper(virDomainPtr dom, unsigned int nfds, int *fds,
+ unsigned int flags)
+{
+ /* Prefer older API unless we have to pass a flag. */
+ if (nfds > 0) {
+ return virDomainCreateWithFiles(dom, nfds, fds, flags);
+ } else if (flags != 0) {
+ return virDomainCreateWithFlags(dom, flags);
+ } else {
+ return virDomainCreate(dom);
+ }
+}
+
static bool
cmdStart(vshControl *ctl, const vshCmd *cmd)
{
g_autoptr(virshDomain) dom = NULL;
#ifndef WIN32
bool console = vshCommandOptBool(cmd, "console");
+ bool resume_domain = false;
#endif
unsigned int flags = VIR_DOMAIN_NONE;
int rc;
@@ -4083,8 +4098,14 @@ cmdStart(vshControl *ctl, const vshCmd *cmd)
if (virshFetchPassFdsList(ctl, cmd, &nfds, &fds) < 0)
return false;
- if (vshCommandOptBool(cmd, "paused"))
+ if (vshCommandOptBool(cmd, "paused")) {
flags |= VIR_DOMAIN_START_PAUSED;
+#ifndef WIN32
+ } else if (console) {
+ flags |= VIR_DOMAIN_START_PAUSED;
+ resume_domain = true;
+#endif
+ }
if (vshCommandOptBool(cmd, "autodestroy"))
flags |= VIR_DOMAIN_START_AUTODESTROY;
if (vshCommandOptBool(cmd, "bypass-cache"))
@@ -4096,12 +4117,7 @@ cmdStart(vshControl *ctl, const vshCmd *cmd)
/* We can emulate force boot, even for older servers that reject it. */
if (flags & VIR_DOMAIN_START_FORCE_BOOT) {
- if (nfds > 0) {
- rc = virDomainCreateWithFiles(dom, nfds, fds, flags);
- } else {
- rc = virDomainCreateWithFlags(dom, flags);
- }
-
+ rc = virDomainCreateHelper(dom, nfds, fds, flags);
if (rc == 0)
goto started;
@@ -4124,14 +4140,18 @@ cmdStart(vshControl *ctl, const vshCmd *cmd)
flags &= ~VIR_DOMAIN_START_FORCE_BOOT;
}
- /* Prefer older API unless we have to pass a flag. */
- if (nfds > 0) {
- rc = virDomainCreateWithFiles(dom, nfds, fds, flags);
- } else if (flags != 0) {
- rc = virDomainCreateWithFlags(dom, flags);
- } else {
- rc = virDomainCreate(dom);
+ rc = virDomainCreateHelper(dom, nfds, fds, flags);
+#ifndef WIN32
+ /* If the driver does not support the paused flag, let's fallback to the old
+ * behavior without the flag. */
+ if (rc < 0 && resume_domain && last_error && last_error->code == VIR_ERR_INVALID_ARG) {
+ vshResetLibvirtError();
+
+ flags &= ~VIR_DOMAIN_START_PAUSED;
+ resume_domain = false;
+ rc = virDomainCreateHelper(dom, nfds, fds, flags);
}
+#endif
if (rc < 0) {
vshError(ctl, _("Failed to start domain '%1$s'"), virDomainGetName(dom));
@@ -4142,7 +4162,7 @@ cmdStart(vshControl *ctl, const vshCmd *cmd)
vshPrintExtra(ctl, _("Domain '%1$s' started\n"),
virDomainGetName(dom));
#ifndef WIN32
- if (console && !cmdRunConsole(ctl, dom, NULL, false, 0))
+ if (console && !cmdRunConsole(ctl, dom, NULL, resume_domain, 0))
return false;
#endif
--
2.34.1On 9/28/23 17:37, Marc Hartmayer wrote:
> When starting a guest via libvirt (`virsh start --console`), early
> console output was missed because the guest was started first and then
> the console was attached. This patch changes this to the following
> sequence:
>
> 1. create a paused guest
> 2. attach the console
> 3. resume the guest
>
> Reviewed-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
> Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
> ---
> tools/virsh-domain.c | 50 +++++++++++++++++++++++++++++++-------------
> 1 file changed, 35 insertions(+), 15 deletions(-)
>
> diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
> index 5c3c6d18aebf..36670039444c 100644
> --- a/tools/virsh-domain.c
> +++ b/tools/virsh-domain.c
> @@ -4059,12 +4059,27 @@ static const vshCmdOptDef opts_start[] = {
> {.name = NULL}
> };
>
> +static int
> +virDomainCreateHelper(virDomainPtr dom, unsigned int nfds, int *fds,
> + unsigned int flags)
To make naming less confusing, we prefer 'virsh' prefix in virsh instead
of 'vir'. It makes it obvious whether a function is a public libvirt API
(virDomainCreate...) or a virsh helper (virshDomainCreate...)
> +{
> + /* Prefer older API unless we have to pass a flag. */
> + if (nfds > 0) {
> + return virDomainCreateWithFiles(dom, nfds, fds, flags);
> + } else if (flags != 0) {
> + return virDomainCreateWithFlags(dom, flags);
> + } else {
> + return virDomainCreate(dom);
> + }
> +}
> +
> static bool
> cmdStart(vshControl *ctl, const vshCmd *cmd)
> {
> g_autoptr(virshDomain) dom = NULL;
> #ifndef WIN32
> bool console = vshCommandOptBool(cmd, "console");
> + bool resume_domain = false;
> #endif
> unsigned int flags = VIR_DOMAIN_NONE;
> int rc;
> @@ -4083,8 +4098,14 @@ cmdStart(vshControl *ctl, const vshCmd *cmd)
> if (virshFetchPassFdsList(ctl, cmd, &nfds, &fds) < 0)
> return false;
>
> - if (vshCommandOptBool(cmd, "paused"))
> + if (vshCommandOptBool(cmd, "paused")) {
> flags |= VIR_DOMAIN_START_PAUSED;
> +#ifndef WIN32
> + } else if (console) {
> + flags |= VIR_DOMAIN_START_PAUSED;
> + resume_domain = true;
> +#endif
> + }
> if (vshCommandOptBool(cmd, "autodestroy"))
> flags |= VIR_DOMAIN_START_AUTODESTROY;
> if (vshCommandOptBool(cmd, "bypass-cache"))
> @@ -4096,12 +4117,7 @@ cmdStart(vshControl *ctl, const vshCmd *cmd)
>
> /* We can emulate force boot, even for older servers that reject it. */
> if (flags & VIR_DOMAIN_START_FORCE_BOOT) {
> - if (nfds > 0) {
> - rc = virDomainCreateWithFiles(dom, nfds, fds, flags);
> - } else {
> - rc = virDomainCreateWithFlags(dom, flags);
> - }
> -
> + rc = virDomainCreateHelper(dom, nfds, fds, flags);
> if (rc == 0)
> goto started;
>
> @@ -4124,14 +4140,18 @@ cmdStart(vshControl *ctl, const vshCmd *cmd)
> flags &= ~VIR_DOMAIN_START_FORCE_BOOT;
> }
>
> - /* Prefer older API unless we have to pass a flag. */
> - if (nfds > 0) {
> - rc = virDomainCreateWithFiles(dom, nfds, fds, flags);
> - } else if (flags != 0) {
> - rc = virDomainCreateWithFlags(dom, flags);
> - } else {
> - rc = virDomainCreate(dom);
> + rc = virDomainCreateHelper(dom, nfds, fds, flags);
> +#ifndef WIN32
> + /* If the driver does not support the paused flag, let's fallback to the old
> + * behavior without the flag. */
> + if (rc < 0 && resume_domain && last_error && last_error->code == VIR_ERR_INVALID_ARG) {
Long line.
Michal
On 28/09/2023 17.37, Marc Hartmayer wrote: > When starting a guest via libvirt (`virsh start --console`), early > console output was missed because the guest was started first and then > the console was attached. This patch changes this to the following > sequence: > > 1. create a paused guest > 2. attach the console > 3. resume the guest > > Reviewed-by: Boris Fiuczynski <fiuczy@linux.ibm.com> > Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com> > --- > tools/virsh-domain.c | 50 +++++++++++++++++++++++++++++++------------- > 1 file changed, 35 insertions(+), 15 deletions(-) Reviewed-by: Thomas Huth <thuth@redhat.com>
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