Re: [PATCH v4 11/19] pc-bios/s390-ccw: Remove panics from Netboot IPL path

[Thomas Huth]

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>