lkml.org 
[lkml]   [2022]   [May]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH RESEND 0/2] j1939: make sure that sent DAT/CTL frames are marked as TX
From
Date
Hi Oleksij,

On Tue, 2022-05-10 at 06:34 +0200, Oleksij Rempel wrote:
> Hi Devid,
>
> On Mon, May 09, 2022 at 07:07:44PM +0200, Devid Antonio Filoni wrote:
> > Hello,
> >
> > If candump -x is used to dump CAN bus traffic on an interface while a J1939
> > socket is sending multi-packet messages, then the DAT and CTL frames
> > show up as RX instead of TX.
> >
> > This patch series sets to generated struct sk_buff the owning struct sock
> > pointer so that the MSG_DONTROUTE flag can be set by recv functions.
> >
> > I'm not sure that j1939_session_skb_get is needed, I think that session->sk
> > could be directly passed as can_skb_set_owner parameter. This patch
> > is based on j1939_simple_txnext function which uses j1939_session_skb_get.
> > I can provide an additional patch to remove the calls to
> > j1939_session_skb_get function if you think they are not needed.
>
> Thank you for your patches. By testing it I noticed that there is a memory
> leak in current kernel and it seems to be even worse after this patches.
> Found by this test:
> https://github.com/linux-can/can-tests/blob/master/j1939/run_all.sh#L13
>
>
> Can you please investigate it (or wait until I get time to do it).
>
> Regards,
> Oleksij
>

I checked the test you linked and I can see that the number of the
instances of the can_j1939 module increases on each
j1939_ac_100k_dual_can.sh test execution (then the script exits),
however this doesn't seem to be worse with my patches, I have the same
results with the original kernel. Did you execute a particular test to
verify that the memory leak is worse with my patches?
I tried to take a look at all code that I changed in my patches but the
used ref counters seem to be handled correctly in called functions. I
suspected that the issue may be caused by the ref counter increased
in can_skb_set_owner() function but, even if I remove that call from the
j1939_simple_txnext() function in original kernel, I can still reproduce
the memory leak.
I think the issue is somewhere else, I'll try to give another look but I
can't assure nothing.

Best Regards,
Devid

\
 
 \ /
  Last update: 2022-05-10 20:14    [W:0.082 / U:0.260 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site