[QEMU][PATCH v4 06/10] hw/xen/xen-hvm-common: skip ioreq creation on ioreq registration failure

Vikram Garhwal posted 10 patches 2 years, 5 months ago
There is a newer version of this series
[QEMU][PATCH v4 06/10] hw/xen/xen-hvm-common: skip ioreq creation on ioreq registration failure
Posted by Vikram Garhwal 2 years, 5 months ago
From: Stefano Stabellini <stefano.stabellini@amd.com>

On ARM it is possible to have a functioning xenpv machine with only the
PV backends and no IOREQ server. If the IOREQ server creation fails continue
to the PV backends initialization.

Also, moved the IOREQ registration and mapping subroutine to new function
xen_do_ioreq_register().

Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com>
Signed-off-by: Vikram Garhwal <vikram.garhwal@amd.com>
---
 hw/xen/xen-hvm-common.c | 53 ++++++++++++++++++++++++++++-------------
 1 file changed, 36 insertions(+), 17 deletions(-)

diff --git a/hw/xen/xen-hvm-common.c b/hw/xen/xen-hvm-common.c
index e748d8d423..94dbbe97ed 100644
--- a/hw/xen/xen-hvm-common.c
+++ b/hw/xen/xen-hvm-common.c
@@ -777,25 +777,12 @@ err:
     exit(1);
 }
 
-void xen_register_ioreq(XenIOState *state, unsigned int max_cpus,
-                        MemoryListener xen_memory_listener)
+static void xen_do_ioreq_register(XenIOState *state,
+                                           unsigned int max_cpus,
+                                           MemoryListener xen_memory_listener)
 {
     int i, rc;
 
-    state->xce_handle = xenevtchn_open(NULL, 0);
-    if (state->xce_handle == NULL) {
-        perror("xen: event channel open");
-        goto err;
-    }
-
-    state->xenstore = xs_daemon_open();
-    if (state->xenstore == NULL) {
-        perror("xen: xenstore open");
-        goto err;
-    }
-
-    xen_create_ioreq_server(xen_domid, &state->ioservid);
-
     state->exit.notify = xen_exit_notifier;
     qemu_add_exit_notifier(&state->exit);
 
@@ -859,12 +846,44 @@ void xen_register_ioreq(XenIOState *state, unsigned int max_cpus,
     QLIST_INIT(&state->dev_list);
     device_listener_register(&state->device_listener);
 
+    return;
+
+err:
+    error_report("xen hardware virtual machine initialisation failed");
+    exit(1);
+}
+
+void xen_register_ioreq(XenIOState *state, unsigned int max_cpus,
+                        MemoryListener xen_memory_listener)
+{
+    int rc;
+
+    state->xce_handle = xenevtchn_open(NULL, 0);
+    if (state->xce_handle == NULL) {
+        perror("xen: event channel open");
+        goto err;
+    }
+
+    state->xenstore = xs_daemon_open();
+    if (state->xenstore == NULL) {
+        perror("xen: xenstore open");
+        goto err;
+    }
+
+    rc = xen_create_ioreq_server(xen_domid, &state->ioservid);
+    if (!rc) {
+        xen_do_ioreq_register(state, max_cpus, xen_memory_listener);
+    } else {
+        warn_report("xen: failed to create ioreq server");
+    }
+
     xen_bus_init();
 
     xen_register_backend(state);
 
     return;
+
 err:
-    error_report("xen hardware virtual machine initialisation failed");
+    error_report("xen hardware virtual machine backend registration failed");
     exit(1);
 }
-- 
2.17.0
Re: [QEMU][PATCH v4 06/10] hw/xen/xen-hvm-common: skip ioreq creation on ioreq registration failure
Posted by Stefano Stabellini 2 years, 5 months ago
On Wed, 25 Jan 2023, Vikram Garhwal wrote:
> From: Stefano Stabellini <stefano.stabellini@amd.com>
> 
> On ARM it is possible to have a functioning xenpv machine with only the
> PV backends and no IOREQ server. If the IOREQ server creation fails continue
> to the PV backends initialization.
> 
> Also, moved the IOREQ registration and mapping subroutine to new function
> xen_do_ioreq_register().
> 
> Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com>
> Signed-off-by: Vikram Garhwal <vikram.garhwal@amd.com>

as per my previous reply, even though I am listed as co-author, for
tracking that I did review this version of the patch:

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>


> ---
>  hw/xen/xen-hvm-common.c | 53 ++++++++++++++++++++++++++++-------------
>  1 file changed, 36 insertions(+), 17 deletions(-)
> 
> diff --git a/hw/xen/xen-hvm-common.c b/hw/xen/xen-hvm-common.c
> index e748d8d423..94dbbe97ed 100644
> --- a/hw/xen/xen-hvm-common.c
> +++ b/hw/xen/xen-hvm-common.c
> @@ -777,25 +777,12 @@ err:
>      exit(1);
>  }
>  
> -void xen_register_ioreq(XenIOState *state, unsigned int max_cpus,
> -                        MemoryListener xen_memory_listener)
> +static void xen_do_ioreq_register(XenIOState *state,
> +                                           unsigned int max_cpus,
> +                                           MemoryListener xen_memory_listener)
>  {
>      int i, rc;
>  
> -    state->xce_handle = xenevtchn_open(NULL, 0);
> -    if (state->xce_handle == NULL) {
> -        perror("xen: event channel open");
> -        goto err;
> -    }
> -
> -    state->xenstore = xs_daemon_open();
> -    if (state->xenstore == NULL) {
> -        perror("xen: xenstore open");
> -        goto err;
> -    }
> -
> -    xen_create_ioreq_server(xen_domid, &state->ioservid);
> -
>      state->exit.notify = xen_exit_notifier;
>      qemu_add_exit_notifier(&state->exit);
>  
> @@ -859,12 +846,44 @@ void xen_register_ioreq(XenIOState *state, unsigned int max_cpus,
>      QLIST_INIT(&state->dev_list);
>      device_listener_register(&state->device_listener);
>  
> +    return;
> +
> +err:
> +    error_report("xen hardware virtual machine initialisation failed");
> +    exit(1);
> +}
> +
> +void xen_register_ioreq(XenIOState *state, unsigned int max_cpus,
> +                        MemoryListener xen_memory_listener)
> +{
> +    int rc;
> +
> +    state->xce_handle = xenevtchn_open(NULL, 0);
> +    if (state->xce_handle == NULL) {
> +        perror("xen: event channel open");
> +        goto err;
> +    }
> +
> +    state->xenstore = xs_daemon_open();
> +    if (state->xenstore == NULL) {
> +        perror("xen: xenstore open");
> +        goto err;
> +    }
> +
> +    rc = xen_create_ioreq_server(xen_domid, &state->ioservid);
> +    if (!rc) {
> +        xen_do_ioreq_register(state, max_cpus, xen_memory_listener);
> +    } else {
> +        warn_report("xen: failed to create ioreq server");
> +    }
> +
>      xen_bus_init();
>  
>      xen_register_backend(state);
>  
>      return;
> +
>  err:
> -    error_report("xen hardware virtual machine initialisation failed");
> +    error_report("xen hardware virtual machine backend registration failed");
>      exit(1);
>  }
> -- 
> 2.17.0
> 
>