Re: [PATCH] xen/manage: don't complain about an empty value in control/sysrq node

[Wei Liu]

On Thu, Sep 06, 2018 at 01:26:08PM +0200, Vitaly Kuznetsov wrote:
> When guest receives a sysrq request from the host it acknowledges it by
> writing '\0' to control/sysrq xenstore node. This, however, make xenstore
> watch fire again but xenbus_scanf() fails to parse empty value with "%c"
> format string:
> 
>  sysrq: SysRq : Emergency Sync
>  Emergency Sync complete
>  xen:manage: Error -34 reading sysrq code in control/sysrq
> 
> Ignore -ERANGE the same way we already ignore -ENOENT, empty value in
> control/sysrq is totally legal.
> 
> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>

Reviewed-by: Wei Liu <wei.liu2@xxxxxxxxxx>