On 1/2/20 1:26 AM, Michal Kubecek wrote:
On Thu, Jan 02, 2020 at 12:24:35PM +0530, Naresh Kamboju wrote:
Results from Linaro’s test farm. Regressions on arm64, arm, x86_64, and i386.
While running LTP syscalls accept* test cases on stable-rc-4.19 branch kernel. This report log extracted from qemu_x86_64.
metadata: git branch: linux-4.19.y git repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git git commit: 4e040169e8b7f4e1c50ceb0f6596015ecc67a052 git describe: v4.19.92-112-g4e040169e8b7 make_kernelversion: 4.19.93-rc1 kernel-config: http://snapshots.linaro.org/openembedded/lkft/lkft/sumo/intel-corei7-64/lkft...
Crash log,
BUG: unable to handle kernel paging request at 0000000040000001 [ 23.578222] PGD 138f25067 P4D 138f25067 PUD 0 er run is 0h 15m[ 23.578222] Oops: 0000 [#1] SMP NOPTI [ 23.578222] CPU: 1 PID: 2216 Comm: accept02 Not tainted 4.19.93-rc1 #1 [ 23.578222] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 23.578222] RIP: 0010:__inet_lookup_listener+0x12d/0x300 00s [ts t_buffe r 23.578222] Code: 18 48 85 db 0f 84 fe 00 00 00 48 83 eb 68 0f 84 f4 00 00 00 0f b7 75 d0 44 8b 55 10 45 89 f1 45 31 ff 31 c0 45 89 de 89 75 b0 <4c> 3b 63 30 75 43 66 44 3b 6b 0e 75 3c 0f b6 73 13 40 f6 c6 20 75 [ 23.578222] RSP: 0018:ffff9e0dbba83c38 EFLAGS: 00010206 [ 23.578222] RAX: ffff9e0db6ff8a80 RBX: 000000003fffffd1 RCX: 0000000000000000 [ 23.578222] RDX: 0000000000000006 RSI: 0000000000000000 RDI: 00000000ffffffff [ 23.578222] RBP: ffff9e0dbba83c88 R08: 000000000100007f R09: 0000000000000000 [ 23.578222] R10: 000000000100007f R11: 0000000000000000 R12: ffffffffbeb2fe40 [ 23.578222] R13: 000000000000d59f R14: 0000000000000000 R15: 0000000000000006 [ 23.578222] FS: 00007fbb30e57700(0000) GS:ffff9e0dbba80000(0000) knlGS:0000000000000000 [ 23.578222] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 23.578222] CR2: 0000000040000001 CR3: 000000013276c000 CR4: 00000000003406e0 [ 23.578222] Call Trace: [ 23.578222] <IRQ> [ 23.578222] tcp_v4_rcv+0x4fe/0xc80 [ 23.578222] ip_local_deliver_finish+0xaf/0x390 [ 23.578222] ip_local_deliver+0x1a1/0x200 [ 23.578222] ? ip_sublist_rcv+0x420/0x420 [ 23.578222] ip_rcv_finish+0x88/0xd0 s.c:55: INFO: Te[ 23.578222] ip_rcv+0x142/0x200 [ 23.578222] ? ip_rcv_finish_core.isra.18+0x4e0/0x4e0 st is[ us ing guar 23.578222] ? process_backlog+0x6d/0x230 [ 23.578222] __netif_receive_skb_one_core+0x57/0x80 ded [bu ffe rs ac2c3.578222] __netif_receive_skb+0x18/0x60 [ 23.578222] process_backlog+0xd4/0x230 [ 23.578222] net_rx_action+0x13e/0x420 [ 23.578222] ? __do_softirq+0x9b/0x426 [ 23.578222] __do_softirq+0xc7/0x426 [ 23.578222] ? ip_finish_output2+0x255/0x660 [ 23.578222] do_softirq_own_stack+0x2a/0x40 [ 23.578222] </IRQ> [ 23.578222] do_softirq.part.19+0x4d/0x60 [ 23.578222] __local_bh_enable_ip+0xd9/0xf0 [ 23.578222] ip_finish_output2+0x27e/0x660 [ 23.578222] ip_finish_output+0x235/0x370 [ 23.578222] ? ip_finish_output+0x235/0x370 [ 23.578222] ip_output+0x76/0x250 [ 23.578222] ? ip_fragment.constprop.50+0x80/0x80 [ 23.578222] ip_local_out+0x3f/0x70 [ 23.578222] __ip_queue_xmit+0x1ea/0x5f0 [ 23.578222] ? __lock_is_held+0x5a/0xa0 [ 23.578222] ip_queue_xmit+0x10/0x20 [ 23.578222] __tcp_transmit_skb+0x57c/0xb60 [ 23.578222] tcp_connect+0xccd/0x1030 [ 23.578222] tcp_v4_connect+0x515/0x550 [ 23.578222] __inet_stream_connect+0x249/0x390 [ 23.578222] ? __local_bh_enable_ip+0x7f/0xf0 [ 23.578222] inet_stream_connect+0x3b/0x60 [ 23.578222] __sys_connect+0xa3/0x120 [ 23.578222] ? kfree+0x203/0x240 [ 23.578222] ? syscall_trace_enter+0x1e3/0x350 [ 23.578222] ? trace_hardirqs_off_caller+0x22/0xf0 [ 23.578222] ? do_syscall_64+0x17/0x1a0 [ 23.578222] ? lockdep_hardirqs_on+0xef/0x180 [ 23.578222] ? do_syscall_64+0x17/0x1a0 [ 23.578222] __x64_sys_connect+0x1a/0x20 [ 23.578222] do_syscall_64+0x55/0x1a0 [ 23.578222] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 23.578222] RIP: 0033:0x7fbb31a1c927 [ 23.578222] Code: 44 00 00 41 54 41 89 d4 55 48 89 f5 53 89 fb 48 83 ec 10 e8 0b f9 ff ff 44 89 e2 48 89 ee 89 df 41 89 c0 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 33 44 89 c7 89 44 24 0c e8 45 f9 ff ff 8b 44
In __inet_lookup_listener(), we need to replace
sk_for_each_rcu(sk, &ilb->head)
by
sk_nulls_for_each_rcu(sk2, node, &ilb->nulls_head)
This loop was eliminated in mainline 5.0-rc1 by commit d9fbc7f6431f ("net: tcp: prefer listeners bound to an address"). I'll have to check if there are more places in stable-4.14 and stable-4.19 which also need to be updated.
Thanks for looking at this.
This also makes me think... AFAICS, since commit d9fbc7f6431f, only the (addr,port) hashtable is used for listener lookup and the traditional port only hashtable is only used to iterate through all listening sockets for netlink dumps and /proc/net/tcp. Maybe we could switch these two also to the (addr,port) hashtable and keep only one listener hashtable.
Yes, this seems something we can do, thanks.