[ovs-dev] [PATCH] ofproto/bond: Fix a race condition in updating post recirculation rules

[Andy Zhou]

Thanks for the review. Will push with changes suggested to give
credits to Salvatore. Will also back-port it to branch-2.3.

On Tue, Feb 17, 2015 at 1:54 PM, Ben Pfaff <blp at nicira.com> wrote:
> On Tue, Feb 17, 2015 at 01:52:44PM -0800, Ben Pfaff wrote:
>> On Tue, Feb 17, 2015 at 01:01:50PM -0800, Andy Zhou wrote:
>> > When updating post recirc rules, rule management requires calls to
>> > hmap APIs, which requires proper locking to ensure mutual exclsion in
>> > accessing the hmap internal data structure. The locking currently is
>> > missing from the output_normal() xlate path, thus causing
>> > a race condition.
>> >
>> > The race condition leads to segfault crash of ovs-vswitchd, with the
>> > following stack trace:
>> >
>> > The crash was found by adding and deleting bond interfaces repeatedly
>> > with on-going traffic hitting the bond interfaces.  The same test was
>> > ran over multiple days with this patch to ensure the same crash was
>> > not seen.
>> >
>> > The patch added the necessary lock annotation that would have caught
>> > the bug.
>> >
>> > Reported-by: Salvator Cambria <salvatore.cambria at citrix.com>
>> > Signed-off-by: Andy Zhou <azhou at nicira.com>
>>
>> I think that Salvator also ran the tests you mention?  If so, I'd
>> credit him with a Tested-by: line in addition to the Reported-by.
>>
>> Acked-by: Ben Pfaff <blp at nicira.com>
>
> Oh, also I believe that his name is spelled "Salvatore", with an "e".
> Please also credit him with a line in the list of bug reporters in
> AUTHORS.