From: Jared Rossi <jrossi@linux.ibm.com>

Remove panic-on-error from Netboot specific functions so that error recovery
may be possible in the future.

Functions that would previously panic now provide a return code.

Signed-off-by: Jared Rossi <jrossi@linux.ibm.com>
---
 pc-bios/s390-ccw/s390-ccw.h   |  2 +-
 pc-bios/s390-ccw/bootmap.c    |  1 +
 pc-bios/s390-ccw/netmain.c    | 17 +++++++++++------
 pc-bios/s390-ccw/virtio-net.c |  7 +++++--
 4 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/pc-bios/s390-ccw/s390-ccw.h b/pc-bios/s390-ccw/s390-ccw.h
index 3e844abd71..344ad15655 100644
--- a/pc-bios/s390-ccw/s390-ccw.h
+++ b/pc-bios/s390-ccw/s390-ccw.h
@@ -57,7 +57,7 @@ unsigned int get_loadparm_index(void);
 void main(void);
 
 /* netmain.c */
-void netmain(void);
+int netmain(void);
 
 /* sclp.c */
 void sclp_print(const char *string);
diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
index a277fc3431..f1cfb7aaa8 100644
--- a/pc-bios/s390-ccw/bootmap.c
+++ b/pc-bios/s390-ccw/bootmap.c
@@ -1073,6 +1073,7 @@ void zipl_load(void)
 
     if (virtio_get_device_type() == VIRTIO_ID_NET) {
         netmain();
+        panic("\n! Cannot IPL from this network !\n");
     }
 
     if (ipl_scsi()) {
diff --git a/pc-bios/s390-ccw/netmain.c b/pc-bios/s390-ccw/netmain.c
index bc6ad8695f..0bb359e09f 100644
--- a/pc-bios/s390-ccw/netmain.c
+++ b/pc-bios/s390-ccw/netmain.c
@@ -464,7 +464,7 @@ static bool find_net_dev(Schib *schib, int dev_no)
     return false;
 }
 
-static void virtio_setup(void)
+static bool virtio_setup(void)
 {
     Schib schib;
     int ssid;
@@ -495,10 +495,10 @@ static void virtio_setup(void)
         }
     }
 
-    IPL_assert(found, "No virtio net device found");
+    return found;
 }
 
-void netmain(void)
+int netmain(void)
 {
     filename_ip_t fn_ip;
     int rc, fnlen;
@@ -506,11 +506,15 @@ void netmain(void)
     sclp_setup();
     puts("Network boot starting...");
 
-    virtio_setup();
+    if (!virtio_setup()) {
+        puts("No virtio net device found.");
+        return 1;
+    }
 
     rc = net_init(&fn_ip);
     if (rc) {
-        panic("Network initialization failed. Halting.");
+        puts("Network initialization failed.");
+        return 1;
     }
 
     fnlen = strlen(fn_ip.filename);
@@ -528,5 +532,6 @@ void netmain(void)
         jump_to_low_kernel();
     }
 
-    panic("Failed to load OS from network.");
+    puts("Failed to load OS from network.");
+    return 1;
 }
diff --git a/pc-bios/s390-ccw/virtio-net.c b/pc-bios/s390-ccw/virtio-net.c
index 2fcb0a58c5..f9854a22c3 100644
--- a/pc-bios/s390-ccw/virtio-net.c
+++ b/pc-bios/s390-ccw/virtio-net.c
@@ -54,8 +54,11 @@ int virtio_net_init(void *mac_addr)
     vdev->guest_features[0] = VIRTIO_NET_F_MAC_BIT;
     virtio_setup_ccw(vdev);
 
-    IPL_assert(vdev->guest_features[0] & VIRTIO_NET_F_MAC_BIT,
-               "virtio-net device does not support the MAC address feature");
+    if (!(vdev->guest_features[0] & VIRTIO_NET_F_MAC_BIT)) {
+        puts("virtio-net device does not support the MAC address feature");
+        return -1;
+    }
+
     memcpy(mac_addr, vdev->config.net.mac, ETH_ALEN);
 
     for (i = 0; i < 64; i++) {
-- 
2.45.1

On 17/10/2024 03.47, jrossi@linux.ibm.com wrote:
> From: Jared Rossi <jrossi@linux.ibm.com>
> 
> Remove panic-on-error from Netboot specific functions so that error recovery
> may be possible in the future.
> 
> Functions that would previously panic now provide a return code.
> 
> Signed-off-by: Jared Rossi <jrossi@linux.ibm.com>
> ---
>   pc-bios/s390-ccw/s390-ccw.h   |  2 +-
>   pc-bios/s390-ccw/bootmap.c    |  1 +
>   pc-bios/s390-ccw/netmain.c    | 17 +++++++++++------
>   pc-bios/s390-ccw/virtio-net.c |  7 +++++--
>   4 files changed, 18 insertions(+), 9 deletions(-)
> 
> diff --git a/pc-bios/s390-ccw/s390-ccw.h b/pc-bios/s390-ccw/s390-ccw.h
> index 3e844abd71..344ad15655 100644
> --- a/pc-bios/s390-ccw/s390-ccw.h
> +++ b/pc-bios/s390-ccw/s390-ccw.h
> @@ -57,7 +57,7 @@ unsigned int get_loadparm_index(void);
>   void main(void);
>   
>   /* netmain.c */
> -void netmain(void);
> +int netmain(void);
>   
>   /* sclp.c */
>   void sclp_print(const char *string);
> diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
> index a277fc3431..f1cfb7aaa8 100644
> --- a/pc-bios/s390-ccw/bootmap.c
> +++ b/pc-bios/s390-ccw/bootmap.c
> @@ -1073,6 +1073,7 @@ void zipl_load(void)
>   
>       if (virtio_get_device_type() == VIRTIO_ID_NET) {
>           netmain();
> +        panic("\n! Cannot IPL from this network !\n");
>       }
>   
>       if (ipl_scsi()) {
> diff --git a/pc-bios/s390-ccw/netmain.c b/pc-bios/s390-ccw/netmain.c
> index bc6ad8695f..0bb359e09f 100644
> --- a/pc-bios/s390-ccw/netmain.c
> +++ b/pc-bios/s390-ccw/netmain.c
> @@ -464,7 +464,7 @@ static bool find_net_dev(Schib *schib, int dev_no)
>       return false;
>   }
>   
> -static void virtio_setup(void)
> +static bool virtio_setup(void)
>   {
>       Schib schib;
>       int ssid;
> @@ -495,10 +495,10 @@ static void virtio_setup(void)
>           }
>       }
>   
> -    IPL_assert(found, "No virtio net device found");
> +    return found;
>   }
>   
> -void netmain(void)
> +int netmain(void)
>   {
>       filename_ip_t fn_ip;
>       int rc, fnlen;
> @@ -506,11 +506,15 @@ void netmain(void)
>       sclp_setup();
>       puts("Network boot starting...");
>   
> -    virtio_setup();
> +    if (!virtio_setup()) {
> +        puts("No virtio net device found.");
> +        return 1;
> +    }
>   
>       rc = net_init(&fn_ip);
>       if (rc) {
> -        panic("Network initialization failed. Halting.");
> +        puts("Network initialization failed.");
> +        return 1;
>       }
>   
>       fnlen = strlen(fn_ip.filename);
> @@ -528,5 +532,6 @@ void netmain(void)
>           jump_to_low_kernel();
>       }
>   
> -    panic("Failed to load OS from network.");
> +    puts("Failed to load OS from network.");
> +    return 1;
>   }

I'd maybe also change the netmain() function to return -1 in case of errors.

Anyway:
Reviewed-by: Thomas Huth <thuth@redhat.com>