[LU-7536] racer_1 test: mds crash : BUG: unable to handle kernel NULL pointer dereference at (null) Oops: 0010 [#1] SMP

• Type: Bug
• Resolution: Fixed
• Priority: Blocker
• Fix Version/s: Lustre 2.9.0
• Affects Version/s: Lustre 2.8.0
• Labels: patch
• Environment: Server 2.7.63 Client 2.7.63; Configuration : 4 node_dne_singlemds - 1 MDS with DNE, 1 OSS, 2 clients; Release; 2.6.32_431.29.2.el6_lustremaster_master__77_g2d11035 Build Date: Sat 05 Dec 2015 05:40:23 PM UTC
• Severity: 3
• Assignee: WC Triage
• Reporter: parinay v kondekar (Inactive)

Description

<1>BUG: unable to handle kernel NULL pointer dereference at (null)
<1>IP: [<(null)>] (null)
<4>PGD 0 
<4>Oops: 0010 [#1] SMP 
<4>last sysfs file: /sys/devices/system/cpu/online
<4>CPU 0 
<4>Modules linked in: osp(U) mdd(U) lod(U) mdt(U) lfsck(U) mgs(U) mgc(U) osd_ldiskfs(U) lquota(U) lustre(U) lov(U) mdc(U) fid(U) lmv(U) fld(U) ksocklnd(U) ptlrpc(U) obdclass(U) lnet(U) sha512_generic sha256_generic libcfs(U) ldiskfs(U) nfs lockd fscache auth_rpcgss nfs_acl sunrpc ipt_REJECT ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ipv6 virtio_balloon virtio_net i2c_piix4 i2c_core ext4 jbd2 mbcache virtio_blk virtio_pci virtio_ring virtio pata_acpi ata_generic ata_piix dm_mirror dm_region_hash dm_log dm_mod [last unloaded: nf_defrag_ipv4]
<4>
<4>Pid: 7661, comm: mdt00_016 Not tainted 2.6.32-431.29.2.el6_lustremaster_master__77 #1 Red Hat KVM
<4>RIP: 0010:[<0000000000000000>]  [<(null)>] (null)
<4>RSP: 0018:ffff880056cefca8  EFLAGS: 00010246
<4>RAX: 0000000000000009 RBX: ffff880056c0b800 RCX: ffff88007c2aea20
<4>RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880056c0b800
<4>RBP: ffff880056cefcc0 R08: 0000000000000009 R09: 0000000000000000
<4>R10: ffff880055063a40 R11: 0000000000000080 R12: 0000000000000000
<4>R13: ffff8800558636c0 R14: 0000000000000000 R15: ffff880055863930
<4>FS:  0000000000000000(0000) GS:ffff880002200000(0000) knlGS:0000000000000000
<4>CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
<4>CR2: 0000000000000000 CR3: 0000000079ad2000 CR4: 00000000000006f0
<4>DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
<4>DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
<4>Process mdt00_016 (pid: 7661, threadinfo ffff880056cee000, task ffff880079413500)
<4>Stack:
<4> ffffffffa0d9dc85 0000000000000001 ffff880056c0b800 ffff880056cefd00
<4><d> ffffffffa0d7cc79 ffff880056cefd00 ffff880057193bc0 ffff880056c0b800
<4><d> 0000000000000009 0000000000000107 ffff880037bfe0b0 ffff880056cefd40
<4>Call Trace:
<4> [<ffffffffa0d9dc85>] ? mdt_reconstruct+0x45/0x120 [mdt]
<4> [<ffffffffa0d7cc79>] mdt_reint_internal+0xa89/0xb80 [mdt]
<4> [<ffffffffa0d7d20b>] mdt_reint+0x6b/0x120 [mdt]
<4> [<ffffffffa073d6fc>] tgt_request_handle+0x8bc/0x12e0 [ptlrpc]
<4> [<ffffffffa06e4a21>] ptlrpc_main+0xe41/0x1910 [ptlrpc]
<4> [<ffffffffa06e3be0>] ? ptlrpc_main+0x0/0x1910 [ptlrpc]
<4> [<ffffffff8109abf6>] kthread+0x96/0xa0
<4> [<ffffffff8100c20a>] child_rip+0xa/0x20
<4> [<ffffffff8109ab60>] ? kthread+0x0/0xa0
<4> [<ffffffff8100c200>] ? child_rip+0x0/0x20
<4>Code:  Bad RIP value.
<1>RIP  [<(null)>] (null)
<4> RSP <ffff880056cefca8>
<4>CR2: 0000000000000000

Issue Links

• is blocked by: LU-5735 BUG in mdt_reconstruct() runnig racer