kernel issue crash on netstat

[Tufan Deveci]

netstat cli on kernel crash and stop network responding.

[Po-Hsu Lin (cypressyew)]

Hi,
I tried some netstat commands on an Azure instance with kernel 5.0.0-1032-azure, but I can't reproduce this issue.

Can you tell us more about the situation that you encountered here:
 1. What netstat command you're using
 2. Guess you're using 5.0.0-1032-azure on Bionic, is that Correct?
 3. What instance type you're using
 4. What is the crash message?

Thanks

[Tufan Deveci (tufandeveci)]

[ 1349.423877] Call Trace:
[ 1349.423877] __pv_queued_spin_lock_slowpath+0x219/0x280
[ 1349.423877] _raw_spin_lock+0x1f/0x30
[ 1349.423877] __inet_hash+0x64/0x300
[ 1349.423877] inet_hash+0x28/0x50
[ 1349.423877] inet_csk_listen_start+0xb3/0xe0
[ 1349.423877] inet_listen+0x9b/0x1a0
[ 1349.423877] ? aa_sk_perm+0x6b/0x190
[ 1349.423877] ? apparmor_socket_listen+0x25/0x30
[ 1349.423877] ? __sys_listen+0x71/0xb0
[ 1349.423877] ? __x64_sys_listen+0x16/0x20
[ 1349.423877] ? do_syscall_64+0x64/0x1b0
[ 1349.423877] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 1377.423883] watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [apache2:4698]
[ 1377.423883] Modules linked in: veth ipt_MASQUERADE nf_conntrack_netlink nfnetlink xfrm_user xfrm_algo xt_addrtype br_netfilter bridge stp llc microsoft_dependency_agent(POE) bluechannel(POE) aufs xt_owner iptable_security wireguard(OE) overlay xt_conntrack xt_tcpudp iptable_filter xt_nat iptable_nat nf_nat_ipv4 nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 bpfilter nls_iso8859_1 hv_balloon serio_raw joydev sch_fq_codel ib_iser rdma_cm iw_cm ib_cm ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ip_tables x_tables autofs4 btrfs zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear crct10dif_pclmul crc32_pclmul ghash_clmulni_intel hid_generic aesni_intel aes_x86_64 crypto_simd cryptd glue_helper pata_acpi hid_hyperv hyperv_keyboard hid hyperv_fb cfbfillrect cfbimgblt cfbcopyarea hv_utils hv_netvsc
[ 1377.423883] CPU: 0 PID: 4698 Comm: apache2 Tainted: P D OEL 5.0.0-1032-azure #34-Ubuntu
[ 1377.423883] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090007 06/02/2017
[ 1377.423883] RIP: 0010:hv_qlock_wait+0x25/0x60
[ 1377.423883] Code: 38 be 00 5d c3 0f 1f 44 00 00 55 48 89 e5 53 65 8b 05 2f 75 df 41 a9 00 00 10 00 75 0d 9c 5b fa 0f b6 07 40 38 c6 74 05 53 9d <5b> 5d c3 b9 f0 00 00 40 0f 32 0f 1f 44 00 00 eb ed 48 c1 e2 20 bf