2020-05-11 07:44:40

by Jürgen Groß

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

backend_connect() can fail, so switch the device to connected only if
no error occurred.

Fixes: 0a9c75c2c7258f2 ("xen/pvcalls: xenbus state handling")
Cc: [email protected]
Signed-off-by: Juergen Gross <[email protected]>
---
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;
xenbus_switch_state(dev, XenbusStateConnected);
break;
case XenbusStateClosing:
--
2.26.1

2020-05-11 21:44:34

by Stefano Stabellini

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

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: [email protected]
> Signed-off-by: Juergen Gross <[email protected]>

Reviewed-by: Stefano Stabellini <[email protected]>


> ---
> 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?

> xenbus_switch_state(dev, XenbusStateConnected);
> break;
> case XenbusStateClosing:
> --
> 2.26.1
>

2020-05-12 04:28:15

by Jürgen Groß

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

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: [email protected]
>> Signed-off-by: Juergen Gross <[email protected]>
>
> Reviewed-by: Stefano Stabellini <[email protected]>
>
>
>> ---
>> 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