On Thu, 2021-03-04 at 08:46 +0100, Florian Westphal wrote: > Mark Tomlinson <mark.tomlinson@xxxxxxxxxxxxxxxxxxx> wrote: > > Changing to using smp_mb() instead of smp_wmb() fixes the kernel panic > > reported in cc00bcaa5899, > > Can you reproduce the crashes without this change? Yes. In our test environment we were seeing a kernel panic approx. twice a day, with a similar output to that shown in Subash's patch (cc00bcaa5899). With this patch we are not seeing any issue. The CPU is a dual-core ARM Cortex-A9. > > How much of an impact is the MB change on the packet path? I will run our throughput tests and get these results. I have a script which makes around 200 calls to iptables. This was taking 11.59s and now is back to 1.16s.
