[LU-5735] BUG in mdt_reconstruct() runnig racer

• Type: Bug
• Resolution: Unresolved
• Priority: Minor
• Affects Version/s: Lustre 2.7.0
• Labels: mdt
• Severity: 3
• Assignee: Di Wang
• Reporter: John Hammond

Description

Racer crashed in a full session https://testing.hpdd.intel.com/test_sets/f66a5bfe-460e-11e4-b3aa-5254006e85c2 with a call to 0 from mdt_reconstruct(). The version running was v2_6_52_0-90-ge12bbee.

/export/scratch/dumps/shadow-7vm8.shadow.whamcloud.com/10.1.4.75-2014-09-26-09:42:24/vmcore-dmesg.txt

<3>LustreError: 1568:0:(mdt_reint.c:1516:mdt_reint_migrate_internal()) lustre-MDT0000: parent [0x3c0000401:0x10a3:0x0] is still on the same MDT, which should be migrated first: rc = -1
<3>LustreError: 1568:0:(mdt_reint.c:1516:mdt_reint_migrate_internal()) Skipped 50 previous similar messages
<4>Lustre: lustre-MDT0000: Client 3540db83-6dfd-a046-25c3-475ebcb2a31e (at 10.1.4.73@tcp) reconnecting
<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 1
<4>Modules linked in: osp(U) mdd(U) lod(U) mdt(U) lfsck(U) mgs(U) nodemap(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) libcfs(U) ldiskfs(U) sh\
a512_generic sha256_generic jbd2 nfsd exportfs nfs lockd fscache auth_rpcgss nfs_acl sunrpc ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm ib_addr ipv6 ib_sa ib_mad ib_core microcode virtio_balloon 8139t\
oo 8139cp mii i2c_piix4 i2c_core ext3 jbd 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: libcfs]
<4>
<4>Pid: 1553, comm: mdt00_008 Not tainted 2.6.32-431.29.2.el6_lustre.gd7c33c1.x86_64 #1 Red Hat KVM
<4>RIP: 0010:[<0000000000000000>]  [<(null)>] (null)
<4>RSP: 0018:ffff880075af1ca8  EFLAGS: 00010246
<4>RAX: 0000000000000009 RBX: ffff880063d15000 RCX: 0000000000000040
<4>RDX: 00054252f84e66b8 RSI: 0000000000000000 RDI: ffff880063d15000
<4>RBP: ffff880075af1cc0 R08: 0000000000000007 R09: 0000000000000000
<4>R10: ffff88006bf5a000 R11: 0000000000001000 R12: 0000000000000000
<4>R13: 0000000000000009 R14: 0000000000000000 R15: 0000000000000000
<4>FS:  0000000000000000(0000) GS:ffff880002300000(0000) knlGS:0000000000000000
<4>CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
<4>CR2: 0000000000000000 CR3: 000000007d1ee000 CR4: 00000000000006e0
<4>DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
<4>DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
<4>Process mdt00_008 (pid: 1553, threadinfo ffff880075af0000, task ffff88007c970ae0)
<4>Stack:
<4> ffffffffa1a2c2f5 ffff880063d15000 ffff8800682ad400 ffff880075af1d00
<4><d> ffffffffa1a03eea ffff880075af1d00 ffff88007d7ecc00 ffff880063d15000
<4><d> 0000000000000009 ffffffffa1a71b90 0000000000000001 ffff880075af1d40
<4>Call Trace:
<4> [<ffffffffa1a2c2f5>] ? mdt_reconstruct+0x45/0x120 [mdt]
<4> [<ffffffffa1a03eea>] mdt_reint_internal+0x70a/0x7b0 [mdt]
<4> [<ffffffffa1a0451b>] mdt_reint+0x6b/0x120 [mdt]
<4> [<ffffffffa1232aee>] tgt_request_handle+0x71e/0xb10 [ptlrpc]
<4> [<ffffffffa11e23d4>] ptlrpc_main+0xe64/0x1990 [ptlrpc]
<4> [<ffffffffa11e1570>] ? ptlrpc_main+0x0/0x1990 [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 <ffff880075af1ca8>
<4>CR2: 0000000000000000
(END)

Issue Links

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