Re: [PATCH] xen: reduce severity of message about using v1 grant tables.

[Jeremy Fitzhardinge <jeremy@goop.org>]

On 12/02/09 11:28, Ian Campbell wrote:
> From: Ian Campbell <ijc@hellion.org.uk>
>
> It's hardly the end of the world...
>
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
> Cc: Jeremy Fitzhardinge <jeremy@goop.org>
> Cc: Steven Smith <Steven.Smith@eu.citrix.com>
> ---
>  drivers/xen/grant-table.c |   19 ++++++++++---------
>  1 files changed, 10 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
> index 2240adf..85ce951 100644
> --- a/drivers/xen/grant-table.c
> +++ b/drivers/xen/grant-table.c
> @@ -699,21 +699,22 @@ static void gnttab_request_version(void)
>  
>  	gsv.version = 2;
>  	rc = HYPERVISOR_grant_table_op(GNTTABOP_set_version, &gsv, 1);
> -	if (rc == 0) {
> +	if (rc == 0)
>  		grant_table_version = 2;
> -		printk(KERN_NOTICE "Using V2 grant tables.\n");
> -	} else {
> +	else {
>  		if (grant_table_version == 2) {
> -			/* If we've already used version 2 features,
> -			   but then suddenly discover that they're not
> -			   available (e.g. migrating to an older
> -			   version of Xen), almost unbounded badness
> -			   can happen. */
> +			/*
> +			 * If we've already used version 2 features,
> +			 * but then suddenly discover that they're not
> +			 * available (e.g. migrating to an older
> +			 * version of Xen), almost unbounded badness
> +			 * can happen.
> +			 */
>  			panic("we need grant tables version 2, but only version 1 is available");
>   

Does it really need to be a panic?  Can't we just start failing all
future operations?  Seems bad to take out the whole machine if we can
just get away with crippling one device (especially if it can be
recovered by downing it and re-upping a new one with nc1 and/or gt1).

    J