>--------- Original Message --------- >Sender : Eric Dumazet <eric.duma...@gmail.com> >Date : 2018-11-08 15:13 (GMT+9) >Title : Re: (2) (2) [Kernel][NET] Bug report on packet defragmenting > >On 11/07/2018 08:26 PM, Eric Dumazet wrote: >> >> >> On 11/07/2018 08:10 PM, 배석진 wrote: >>>> --------- Original Message --------- >>>> Sender : Eric Dumazet <eric.duma...@gmail.com> >>>> Date : 2018-11-08 12:57 (GMT+9) >>>> Title : Re: (2) [Kernel][NET] Bug report on packet defragmenting >>>> >>>> On 11/07/2018 07:24 PM, Eric Dumazet wrote: >>>> >>>>> Sure, it is better if RPS is smarter, but if there is a bug in IPv6 >>>>>defrag unit >>>>> we must investigate and root-cause it. >>>> >>>> BTW, IPv4 defrag seems to have the same issue. >>> >>> >>> yes, it could be. >>> key point isn't limitted to ipv6. >>> >>> maybe because of faster air-network and modem, >>> it looks like occure more often and we got recognized that. >>> >>> anyway, >>> we'll apply our patch to resolve this problem. >> >> Yeah, and I will fix the defrag units. >> >> We can not rely on other layers doing proper no-reorder logic for us. >> >> Problem here is that multiple cpus attempt concurrent >>rhashtable_insert_fast() >> and do not properly recover in case -EEXIST is returned. >> >> This is silly, of course :/ > >Patch would be https://patchwork.ozlabs.org/patch/994658/
Dear Dumazet, with your patch, kernel got the panic when packet recieved. I double checked after disable your patch, then no problem. <6>[ 119.702054] I[3: kworker/u18:1: 1705] LNK-RX(1464): 6b 80 00 00 05 90 2c 3e 20 01 44 30 00 05 04 01 ... <6>[ 119.702120] I[3: kworker/u18:1: 1705] __skb_flow_dissect: ports: 77500000 <6>[ 119.702153] I[3: kworker/u18:1: 1705] get_rps_cpu: cpu:2, hash:2055028308 <6>[ 119.702203] I[3: kworker/u18:1: 1705] LNK-RX(1212): 6b 80 00 00 04 94 2c 3e 20 01 44 30 00 05 04 01 ... <6>[ 119.702231] I[3: kworker/u18:1: 1705] __skb_flow_dissect: ports: 3c7e2c6b <6>[ 119.702258] I[3: kworker/u18:1: 1705] get_rps_cpu: cpu:1, hash:671343869 <6>[ 119.702365] I[1: Binder:11369_2:11382] ipv6_rcv +++ <6>[ 119.702375] I[2: swapper/2: 0] ipv6_rcv +++ <6>[ 119.702406] I[2: swapper/2: 0] ipv6_defrag +++ <6>[ 119.702425] I[1: Binder:11369_2:11382] ipv6_defrag +++ <6>[ 119.702494] I[2: swapper/2: 0] ipv6_defrag: EINPROGRESS <6>[ 119.702522] I[2: swapper/2: 0] ipv6_rcv --- <6>[ 119.702628] I[1: Binder:11369_2:11382] ipv6_defrag --- <6>[ 119.702892] I[1: Binder:11369_2:11382] ipv6_defrag +++ <6>[ 119.702922] I[1: Binder:11369_2:11382] ipv6_defrag --- <6>[ 119.702966] I[1: Binder:11369_2:11382] ipv6_rcv --- <0>[ 119.703792] [1: Binder:11369_2:11382] BUG: sleeping function called from invalid context at arch/arm64/mm/fault.c:518 <3>[ 119.703826] [1: Binder:11369_2:11382] in_atomic(): 0, irqs_disabled(): 0, pid: 11382, name: Binder:11369_2 <3>[ 119.703854] [1: Binder:11369_2:11382] Preemption disabled at: <4>[ 119.703888] [1: Binder:11369_2:11382] [<ffffff80080b13d4>] __do_softirq+0x68/0x3c4 <4>[ 119.703934] [1: Binder:11369_2:11382] CPU: 1 PID: 11382 Comm: Binder:11369_2 Tainted: G S W 4.14.75-20181108-163447-eng #0 <4>[ 119.703960] [1: Binder:11369_2:11382] Hardware name: Samsung BEYOND2LTE KOR SINGLE 19 board based on EXYNOS9820 (DT) <4>[ 119.703987] [1: Binder:11369_2:11382] Call trace: <4>[ 119.704015] [1: Binder:11369_2:11382] [<ffffff80080bd87c>] dump_backtrace+0x0/0x280 <4>[ 119.704045] [1: Binder:11369_2:11382] [<ffffff80080bddd4>] show_stack+0x18/0x24 <4>[ 119.704074] [1: Binder:11369_2:11382] [<ffffff80090bb3f8>] dump_stack+0xb8/0xf8 <4>[ 119.704104] [1: Binder:11369_2:11382] [<ffffff800811f180>] ___might_sleep+0x16c/0x178 <4>[ 119.704132] [1: Binder:11369_2:11382] [<ffffff800811efdc>] __might_sleep+0x4c/0x84 <4>[ 119.704164] [1: Binder:11369_2:11382] [<ffffff80090dcf60>] do_page_fault+0x2e8/0x4b8 <4>[ 119.704193] [1: Binder:11369_2:11382] [<ffffff80090dcbf4>] do_translation_fault+0x7c/0x100 <4>[ 119.704219] [1: Binder:11369_2:11382] [<ffffff80080b0d70>] do_mem_abort+0x4c/0x12c <4>[ 119.704243] [1: Binder:11369_2:11382] Exception stack(0xffffff8038bf3ec0 to 0xffffff8038bf4000) <4>[ 119.704266] [1: Binder:11369_2:11382] 3ec0: 00000077b8262600 00000077b1bd0800 00000000708fcae0 0000000000000018 ... <4>[ 119.704459] [1: Binder:11369_2:11382] 3fe0: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 <4>[ 119.704480] [1: Binder:11369_2:11382] [<ffffff80080b33d0>] el0_da+0x20/0x24 <4>[ 119.704509] [1: Binder:11369_2:11382] ------------[ cut here ]------------ <0>[ 119.704541] [1: Binder:11369_2:11382] kernel BUG at kernel/sched/core.c:6152! <2>[ 119.704563] [1: Binder:11369_2:11382] sec_debug_set_extra_info_fault = BUG / 0xffffff800811f180 <0>[ 119.704603] [1: Binder:11369_2:11382] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
