Yes, we already found these and are included in our kernel, but even with these patches we still receive the panic.
- Johan > On 18 Jul 2015, at 10:56, Eric Dumazet <eric.duma...@gmail.com> wrote: > > On Fri, 2015-07-17 at 21:18 +0000, Johan Schuijt wrote: >> Hey guys, >> >> >> We’re currently running into a reproducible panic in the eviction work >> queue code when we pin al our eth* IRQ to different CPU cores (in >> order to scale our networking performance for our virtual servers). >> This only occurs in kernels >= 3.17 and is a result of the following >> change: >> https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?h=linux-3.18.y&id=b13d3cbfb8e8a8f53930af67d1ebf05149f32c24 >> >> >> The race/panic we see seems to be the same as, or similar to: >> https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?h=linux-3.18.y&id=65ba1f1ec0eff1c25933468e1d238201c0c2cb29 >> >> >> We can confirm that this is directly exposed by the IRQ pinning since >> disabling this stops us from being able to reproduce this case :) >> >> >> How te reproduce: in our test-setup we have 4 machines generating UDP >> packets which are send to the vulnerable host. These all have a MTU of >> 100 (for test purposes) and send UDP packets of a size of 256 bytes. >> Within half an hour you will see the following panic: >> >> >> crash> bt >> PID: 56 TASK: ffff885f3d9fc210 CPU: 9 COMMAND: "kworker/9:0" >> #0 [ffff885f3da03b60] machine_kexec at ffffffff8104a1f7 >> #1 [ffff885f3da03bb0] crash_kexec at ffffffff810db187 >> #2 [ffff885f3da03c80] oops_end at ffffffff81015140 >> #3 [ffff885f3da03ca0] general_protection at ffffffff814f6c88 >> [exception RIP: inet_evict_bucket+281] >> RIP: ffffffff81480699 RSP: ffff885f3da03d58 RFLAGS: 00010292 >> RAX: ffff885f3da03d08 RBX: dead0000001000a8 RCX: >> ffff885f3da03d08 >> RDX: 0000000000000006 RSI: ffff885f3da03ce8 RDI: >> dead0000001000a8 >> RBP: 0000000000000002 R8: 0000000000000286 R9: >> ffff88302f401640 >> R10: 0000000080000000 R11: ffff88602ec0c138 R12: >> ffffffff81a8d8c0 >> R13: ffff885f3da03d70 R14: 0000000000000000 R15: >> ffff881d6efe1a00 >> ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 >> #4 [ffff885f3da03db0] inet_frag_worker at ffffffff8148075a >> #5 [ffff885f3da03e10] process_one_work at ffffffff8107be19 >> #6 [ffff885f3da03e60] worker_thread at ffffffff8107c6e3 >> #7 [ffff885f3da03ed0] kthread at ffffffff8108103e >> #8 [ffff885f3da03f50] ret_from_fork at ffffffff814f4d7c >> >> >> We would love to receive your input on this matter. >> >> >> Thx in advance, >> >> >> - Johan > > Check commits 65ba1f1ec0eff1c25933468e1d238201c0c2cb29 & > d70127e8a942364de8dd140fe73893efda363293 > > Also please send your mails in text format, not html, and CC netdev ( I > did here) > >> >> > >
