[LU-78] kiblnd_check_conns can deadlock

• Type: Bug
• Resolution: Fixed
• Priority: Major
• Fix Version/s: Lustre 2.2.0, Lustre 2.1.2
• Affects Version/s: Lustre 2.0.0, Lustre 1.8.6
• Labels: paj
• Severity: 3
• Bugzilla ID: 20,288
• Assignee: Liang Zhen (Inactive)
• Reporter: Oleg Drokin

Description

kiblnd_check_conns() called kiblnd_check_sends() with read_lock(&kiblnd_data.kib_global_lock), it's
so wrong because kiblnd_check_sends() could do a lot of things:
1. lnet_finalize(), which is not safe with spinlock
2. kiblnd_close_conn(), which will hold write_lock(&kiblnd_data.kib_global_lock) to be bomb of
deadlock

There is a patch in the bug from Isaac, but it introduced som regressions and was therefore reverted.

Issue Links

• Trackbacks: Changelog 2.1 Changes from version 2.1.1 to version 2.1.2 Server support for kernels: 2.6.18308.4.1.el5 (RHEL5) 2.6.32220.17.1.el6 (RHEL6) Client support for unpatched kernels: 2.6.18308.4.1.el5 (RHEL5) 2.6.32220.17.1....
• Trackbacks: Changelog 2.2 version 2.2.0 Support for networks: o2iblnd OFED 1.5.4 Server support for kernels: 2.6.32220.4.2.el6 (RHEL6) Client support for unpatched kernels: 2.6.18274.18.1.el5 (RHEL5) 2.6.32220.4.2.el6 (RHEL6) 2.6.32.360....