[LU-789] bz24546: After upgrade of Lustre from 1.8.2 to 1.8.5 (RHEL 5.4 to 5.5) OST are randomly crashing.

• Type: Bug
• Resolution: Won't Fix
• Priority: Minor
• Affects Version/s: Lustre 1.8.6
• Environment: before 2.6.32 linux kernel
• Severity: 3
• Bugzilla ID: 24,546
• Assignee: Zhenyu Xu
• Reporter: Zhenyu Xu

Description

There is a hack in the dm code where we allocate an extra bi_io_vec to store additional private data. This hack combines with our blkdev tunable patch which adopt MAX_HW_SEGMENTS to 256 will cause bio_alloc_bioset() returns NULL bio, NULL pointer reference ensues.

We need include 2.6.32 upstream patch for the issue (linux kernel commit f1e539874655ae9e74c1644fd54133b19f1b14e2) into blkdev_tunable kernel patch for pre-2.6.32 kernel support release.

Issue Links

• Trackbacks: Lustre 1.8.x known issues tracker While testing against Lustre b18 branch, we would hit known bugs which were already reported in Lustre Bugzilla https://bugzilla.lustre.org/. In order to move away from relying on Bugzilla, we would create a JIRA