Re: [PATCH stable 3.2 3.4] ipv4: disable bh while doing route gc

[Marcelo Ricardo Leitner <mleitner@redhat.com>]

On 13-10-2014 13:52, David Miller wrote:
> From: Marcelo Ricardo Leitner <mleitner@redhat.com>
> Date: Mon, 13 Oct 2014 13:20:38 -0300
>
>> Further tests revealed that after moving the garbage collector to a work
>> queue and protecting it with a spinlock may leave the system prone to
>> soft lockups if bottom half gets very busy.
>>
>> It was reproced with a set of firewall rules that REJECTed packets. If
>> the NIC bottom half handler ends up running on the same CPU that is
>> running the garbage collector on a very large cache, the garbage
>> collector will not be able to do its job due to the amount of work
>> needed for handling the REJECTs and also won't reschedule.
>>
>> The fix is to disable bottom half during the garbage collecting, as it
>> already was in the first place (most calls to it came from softirqs).
>>
>> Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
>> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
>
> Please add my:
>
> Acked-by: David S. Miller <davem@davemloft.net>
>
> and submit this directly to -stable, thanks.

Will do. Thanks.

Marcelo