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charset=us-ascii Content-Disposition: inline In-Reply-To: <789d5cc3c38b320d61867290115acafb060ca752.camel@redhat.com> Thu, Feb 15, 2024 at 01:56:12PM CET, pabeni@redhat.com wrote: >On Wed, 2024-02-14 at 07:04 -0800, Jakub Kicinski wrote: >> On Wed, 14 Feb 2024 09:51:00 +0100 Jiri Pirko wrote: >> > Wed, Feb 14, 2024 at 04:38:47AM CET, kuba@kernel.org wrote: >> > > The test Davide added in commit ca22da2fbd69 ("act_mirred: use the backlog >> > > for nested calls to mirred ingress") hangs our testing VMs every 10 or so >> > > runs, with the familiar tcp_v4_rcv -> tcp_v4_rcv deadlock reported by >> > > lockdep. >> > > >> > > In the past there was a concern that the backlog indirection will >> > > lead to loss of error reporting / less accurate stats. But the current >> > > workaround does not seem to address the issue. >> > >> > Okay, so what the patch actually should change to fix this? >> >> Sorry I'm not sure what you're asking. >> >> We can't redirect traffic back to ourselves because we can end up >> trying to take the socket lock for a socket that is generating >> the packet. >> >> Or are you asking how we can get the stats from the packet >> asynchronously? We could build a local async scheme but I'd rather >> not go there unless someone actually cares about these stats. > >I *guess* Jiri is suggesting to expand the commit message describing >how the fix implemented by this patch works. > >@Jiri, feel free to provide the actual correct interpretation :) Yes, but I was silent not to get beaten by another maintainer for pointing this out :) But really, the patch desctiption should make it simpler to understand the code, that's my motivation. Not to bug people... > >Cheers, > >Paolo >