Re: [PATCH] xen/pvcalls-back: test for errors when calling backend_connect()

["Jürgen Groß" <jgross@suse.com>]

On 11.05.20 23:41, Stefano Stabellini wrote:
> On Mon, 11 May 2020, Juergen Gross wrote:
>> backend_connect() can fail, so switch the device to connected only if
>> no error occurred.
>>
>> Fixes: 0a9c75c2c7258f2 ("xen/pvcalls: xenbus state handling")
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Juergen Gross <jgross@suse.com>
> 
> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
> 
> 
>> ---
>>   drivers/xen/pvcalls-back.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c
>> index cf4ce3e9358d..41a18ece029a 100644
>> --- a/drivers/xen/pvcalls-back.c
>> +++ b/drivers/xen/pvcalls-back.c
>> @@ -1088,7 +1088,8 @@ static void set_backend_state(struct xenbus_device *dev,
>>   		case XenbusStateInitialised:
>>   			switch (state) {
>>   			case XenbusStateConnected:
>> -				backend_connect(dev);
>> +				if (backend_connect(dev))
>> +					return;
> 
> Do you think it would make sense to WARN?

There already should be an error message (either due to a failed
grant mapping or a failed memory allocation).


Juergen