Hi, I get an MCE-related crash like this in latest linus tree: [ 0.115341] CPU: L1 I Cache: 64K (64 bytes/line), D cache 64K (64 bytes/line) [ 0.116396] CPU: L2 Cache: 512K (64 bytes/line) [ 0.120570] mce: CPU supports 0 MCE banks [ 0.124870] BUG: unable to handle kernel NULL pointer dereference at 00000000 00000010 [ 0.128001] IP: [] mcheck_init+0x278/0x320 [ 0.128001] PGD 0 [ 0.128001] Thread overran stack, or stack corrupted [ 0.128001] Oops: 0002 [#1] PREEMPT SMP [ 0.128001] last sysfs file: [ 0.128001] CPU 0 [ 0.128001] Modules linked in: [ 0.128001] Pid: 0, comm: swapper Not tainted 2.6.30 #426 [ 0.128001] RIP: 0010:[] [] mcheck_init+ 0x278/0x320 [ 0.128001] RSP: 0018:ffffffff81595e38 EFLAGS: 00000246 [ 0.128001] RAX: 0000000000000010 RBX: ffffffff8158f900 RCX: 0000000000000000 [ 0.128001] RDX: 0000000000000000 RSI: 00000000000000ff RDI: 0000000000000010 [ 0.128001] RBP: ffffffff81595e68 R08: 0000000000000001 R09: 0000000000000000 [ 0.128001] R10: 0000000000000010 R11: 0000000000000000 R12: 0000000000000000 [ 0.128001] R13: 00000000ffffffff R14: 0000000000000000 R15: 0000000000000000 [ 0.128001] FS: 0000000000000000(0000) GS:ffff880002288000(0000) knlGS:00000 00000000000 [ 0.128001] CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b [ 0.128001] CR2: 0000000000000010 CR3: 0000000001001000 CR4: 00000000000006b0 [ 0.128001] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 0.128001] DR3: 0000000000000000 DR6: 0000000000000000 DR7: 0000000000000000 [ 0.128001] Process swapper (pid: 0, threadinfo ffffffff81594000, task ffffff ff8152a4a0) [ 0.128001] Stack: [ 0.128001] 0000000081595e68 5aa50ed3b4ddbe6e ffffffff8158f900 ffffffff8158f 914 [ 0.128001] ffffffff8158f948 0000000000000000 ffffffff81595eb8 ffffffff813b8 69c [ 0.128001] 5aa50ed3b4ddbe6e 00000001078bfbfd 0000062300000800 5aa50ed3b4ddb e6e [ 0.128001] Call Trace: [ 0.128001] [] identify_cpu+0x331/0x392 [ 0.128001] [] identify_boot_cpu+0x23/0x6e [ 0.128001] [] check_bugs+0x1c/0x60 [ 0.128001] [] start_kernel+0x403/0x46e [ 0.128001] [] x86_64_start_reservations+0xac/0xd5 [ 0.128001] [] x86_64_start_kernel+0x115/0x14b [ 0.128001] [] ? early_idt_handler+0x0/0x71 [ 0.128001] Code: c7 48 89 05 9e 71 40 00 74 2a 48 63 15 91 71 40 00 be ff 00 00 00 48 c1 e2 03 e8 bf a1 e2 ff e9 3f fe ff ff 48 8b 05 7b 71 40 00 <48> c7 00 00 00 00 00 eb 84 c7 05 40 71 40 00 01 00 00 00 e9 2b [ 0.128001] RIP [] mcheck_init+0x278/0x320 [ 0.128001] RSP [ 0.128001] CR2: 0000000000000010 [ 0.129306] ---[ end trace a7919e7f17c0a725 ]--- It's this: /* * Various K7s with broken bank 0 around. Always disable * by default. */ if (c->x86 == 6) bank[0] = 0; in mce_cpu_quirks() in arch/x86/kernel/cpu/mcheck/mce.c around line 1217. Strange that it thinks this is AMD cpu, though? Attached full boot log. Vegard