+++ This bug was initially created as a clone of Bug #452912 +++

Description of problem:
When booting either the bare metal or Xen 2.6.18-92.1.6 kernel, only one CPU is
seen on the new beta Tylersburg-EP systems. There should be 16 CPUs with HT
enabled as they're dual quad-core boxes.

Version-Release number of selected component (if applicable):
Kernel and Kernel-xen 2.6.18-92.1.6

How reproducible:
Every time

Steps to Reproduce:
1. Install RHEL5.2
2. Boot system
3. Only CPU0 can be seen.
4. Update to latest kernels
5. Still only one CPU seen.  

Actual results:
1 logical CPU

Expected results:
16 logical CPUs

Additional info:
The system showed 1 logical CPU with the GA 5.2 xen kernel as well. I looked
through the BIOS, but couldn't see any setting that would account for the single
CPU state.

-- Additional comment from gcase on 2008-06-25 16:50 EST --
Turbo mode and HT BIOS settings don't seem to affect this. I tried turning them
off but still only 1 CPU is seen. 

There are interesting dmesg entries including a soft lockup, and MCE error and
the phrase "weird, boot CPU (#0) not listed by the BIOS". Will the MCE bank
error be addressed by "Bugzilla Bug 446673: FEAT: RHEL 5.3 extend MCE banks
support for Dunnington, Nehalem, and beyond"? I'm attaching dmesg and a
sosreport, but here's the relevant excerpt from dmesg that I'm talking about.


CPU: L1 I cache: 32K, L1 D cache: 32K
CPU: L2 cache: 256K
CPU: L3 cache: 8192K
using mwait in idle threads.
CPU: Physical Processor ID: 0
CPU: Processor Core ID: 0
MCE: warning: using only 9 banks
CPU0: Thermal monitoring enabled (TM1)
SMP alternatives: switching to UP code
Freeing SMP alternatives: 32k freed
weird, boot CPU (#0) not listed by the BIOS.
SMP motherboard not detected.
Using local APIC timer interrupts.
result 8333944
Detected 8.333 MHz APIC timer.
testing NMI watchdog ... OK.
SMP disabled
Brought up 1 CPUs
testing NMI watchdog ... <3>BUG: soft lockup - CPU#0 stuck for 10s! [swapper:1]
CPU 0:
Modules linked in:
Pid: 1, comm: swapper Not tainted 2.6.18-92.1.6.el5 #1
RIP: 0010:[<ffffffff8000c680>]  [<ffffffff8000c680>] __delay+0x6/0x10
RSP: 0000:ffff810110ad9e98  EFLAGS: 00000283
RAX: 000000000008d14c RBX: 0000000000002710 RCX: 00000000236ddd4e
RDX: 0000000000000030 RSI: ffff810110a562c0 RDI: 0000000000252b88
RBP: ffffffff803e5c5c R08: 0000000000000006 R09: ffff8100010203d4
R10: 0000000000000097 R11: ffffffff8015c24b R12: ffffffff803e5c5c
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffffffff8039f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 0000000000000000 CR3: 0000000000201000 CR4: 00000000000006e0

Call Trace:
 [<ffffffff803e5bc0>] check_nmi_watchdog+0x12e/0x1ca
 [<ffffffff803e4f26>] smp_cpus_done+0x25/0x2c
 [<ffffffff803db956>] init+0xf9/0x2f7
 [<ffffffff8005dfb1>] child_rip+0xa/0x11
 [<ffffffff803db85d>] init+0x0/0x2f7
 [<ffffffff8005dfa7>] child_rip+0x0/0x11

OK.
time.c: Using 1.193182 MHz WALL PIT GTOD PIT/TSC timer.
time.c: Detected 2400.178 MHz processor.
sizeof(vma)=176 bytes
sizeof(page)=56 bytes
sizeof(inode)=560 bytes
sizeof(dentry)=216 bytes
sizeof(ext3inode)=760 bytes
sizeof(buffer_head)=96 bytes
sizeof(skbuff)=240 bytes


-- Additional comment from gcase on 2008-06-25 16:52 EST --
Created an attachment (id=310295)
5.2 non-xen dmesg 

This is the entire dmesg output from 2.6.18-92.1.6 non-xen

-- Additional comment from gcase on 2008-06-25 16:54 EST --
Created an attachment (id=310296)
sosreport from affected machine

SOSreport from the Tylersburg-EP beta system

-- Additional comment from gcase on 2008-06-25 17:11 EST --
Toggling the "Limit CPUID Maximum" setting in BIOS also appears to have no
effect on this issue.


-- Additional comment from jvillalo on 2008-06-25 17:27 EST --
This is a known issue with the current SuperMicro BIOS ACPI Tables.  I have read
that SuperMicro is currently working on this issue.

Recommend filing an issue with Intel Premier support so that you will be
notified as soon as a new BIOS is available.