Created attachment 335109 [details] code for test program that causes BUG message Description of problem: Customer running a GTOD test program on HP DL765 & DL385 get a soft lockup BUG. Version-Release number of selected component (if applicable): 2.6.24.7-107.el5rt How reproducible: Every time. Steps to Reproduce: 1. Use provided "timetest6" test program. There is no need to set affinity or set realtime priority. # ps -lef |grep timetest F S UID PID PPID C PRI NI ADDR SZ WCHAN STIME TTY TIME CMD 4 R root 7568 7536 99 -40 - - 1171 - 17:17 pts/0 00:05:43 ./timetest6b 0 2. 3. Actual results: kernel: BUG: soft lockup - CPU#10 stuck for 11s! [timetest6b:7568] kernel: CPU 10: kernel: Modules linked in: ib_iser libiscsi scsi_transport_iscsi ib_srp scsi_transport_srp scsi_tgt ib_sdp ib_ipoib ipv6 rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm ib_addr ib_sa ib_mad ib_core dm_multipath scsi_dh video output sbs sbshc battery ac parport_pc lp parport sg sr_mod button cdrom bnx2 sfc mii serio_raw e1000e e1000 pata_serverworks pata_acpi ata_generic amd64_edac edac_core ipmi_si libata pcspkr ipmi_msghandler shpchp dm_snapshot dm_zero dm_mirror dm_mod cciss sd_mod scsi_mod ext3 jbd mbcache uhci_hcd ohci_hcd ehci_hcd kernel: Pid: 7568, comm: timetest6b Not tainted 2.6.24.7-107.el5rt #1 kernel: RIP: 0033:[<000000000040076f>] [<000000000040076f>] kernel: RSP: 002b:00007fff0d3178c0 EFLAGS: 00000246 kernel: RAX: 0000000000000000 RBX: 00007fff0d317930 RCX: 0000000000000000 kernel: RDX: 0000000008f8e406 RSI: 00007fff0d3178f0 RDI: 00007fff0d3178e0 kernel: RBP: 00007fff0d314fe0 R08: 00007fe6051fe6e0 R09: 00007fe604ebe760 kernel: R10: 0000000000000000 R11: 00007fe604e31610 R12: 000000000000000e kernel: R13: 000000000000000e R14: 00007fe6050f6860 R15: 000000000000000e kernel: FS: 00007fe6051fe6e0(0000) GS:ffff810c2e51f9c0(0000) knlGS:0000000000000000 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b kernel: CR2: 00007fe604e76170 CR3: 0000000c2d56a000 CR4: 00000000000006e0 kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 kernel: DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 kernel: kernel: Call Trace: kernel: kernel: BUG: soft lockup - CPU#10 stuck for 11s! [timetest6b:7620] Expected results: Additional info: On the test hardware (DL765), timetest6 takes about 2 minutes to run.