Greetings,

This bug exists in both upstream and linux-next.

The first bad commit could be any of:
086fc8f8037bf16f55f82c66b26a8b834f7349ec x86/tlbflush.h: Define __native_flush_tlb_global_irq_disabled()
e666dfa273db1b12711eaec91facac5fec2ec851 x86/microcode_intel_lib.c: Early update ucode on Intel's CPU
a8ebf6d1d6971b90a20f5bd0465e6d520377e33b x86/microcode_core_early.c: Define interfaces for early loading ucode
ec400ddeff200b068ddc6c70f7321f49ecf32ed5 x86/microcode_intel_early.c: Early update ucode on Intel's CPU
63b553c68db5a8d4febcd1010b194333d2b02e1c x86/head_32.S: Early update ucode in 32-bit
e6ebf5deaaaa33b661f0db86380c232b162bd68c x86/common.c: load ucode in 64 bit or show loading ucode info in 32 bit on AP
d288e1cf8e62f3e4034f1f021f047009c4ac0b3c x86/common.c: Make have_cpuid_p() a global function
feddc9de8bf69415da6f96eca0219186b70d145a x86/head64.c: Early update ucode in 64-bit
9cd4d78e21cfdc709b1af516214ec4f69ee0e6bd x86/microcode_intel.h: Define functions and macros for early loading ucode
cd745be89e1580e8a1b47454a39f97f9c5c4b1e0 x86/mm/init.c: Copy ucode from initrd image to kernel memory
da76f64e7eb28b718501d15c1b79af560b7ca4ea x86/Kconfig: Make early microcode loading a configuration feature
We cannot bisect more!

Kernel cmdline: hung_task_panic=1 rcutree.rcu_cpu_stall_timeout=100 log_buf_len=8M ignore_loglevel debug sched_debug apic=debug dynamic_printk sysrq_always_enabled panic=10  prompt_ramdisk=0 console=ttyS0,115200 console=tty0 vga=normal  root=/dev/ram0 rw link=/kernel-tests/run-queue/kvm/i386-randconfig-x19-0606/staging:staging-next/.vmlinuz-f2c3d800972670fb49bc0ebaeb02450aa591eb0a-20130606164838-7-xian branch=staging/staging-next  BOOT_IMAGE=/kernel/i386-randconfig-x19-0606/f2c3d800972670fb49bc0ebaeb02450aa591eb0a/vmlinuz-3.10.0-rc3-00579-gf2c3d80

Early crashed kernel: vmlinuz-3.10.0-rc3-00579-gf2c3d80 3.10.0-rc3-00579-gf2c3d80 #5

git bisect start v3.9 v3.8 --
git bisect good d778df51c09264076fe0208c099ef7d428f21790  #    10  2013-06-07 12:22:06  mm: vmscan: save work scanning (almost) empty LRU lists
git bisect  bad ee89f81252179dcbf6cd65bd48299f5e52292d88  #     0  2013-06-07 12:22:10  Merge branch 'for-3.9/core' of git://git.kernel.dk/linux-block
git bisect  bad 69086a78bdc973ec0b722be790b146e84ba8a8c4  #     0  2013-06-07 12:22:15  Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
git bisect  bad d9978ec5680059d727b39d6c706777c6973587f2  #     0  2013-06-07 12:22:16  Merge tag 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev
git bisect  bad 5ce1a70e2f00f0bce0cab57f798ca354b9496169  #     0  2013-06-07 12:22:18  Merge branch 'akpm' (more incoming from Andrew)
git bisect  bad 9d3cae26acb471d5954cfdc25d1438b32060babe  #     0  2013-06-07 12:22:20  Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
git bisect good db8ff907027b63b02c8cef385ea95445b7a41357  #    10  2013-06-07 12:35:25  powerpc: Documentation for transactional memory on powerpc
git bisect  bad 5f32ed140dac726e880d292988ba20d16f545bda  #     0  2013-06-07 12:35:30  Merge branch 'parisc-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
git bisect  bad c68fea3464cbe4f3e1382f9f74a7c04cdbfb92ad  #     0  2013-06-07 12:35:33  Merge tag 'please-pull-fix-ia64-build' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux
git bisect good 41ef8f826692c8f65882bec0a8211bd4d1d2d19a  #    50  2013-06-07 12:35:36  rwsem-spinlock: Implement writer lock-stealing for better scalability
git bisect good 0cc9129d75ef8993702d97ab0e49542c15ac6ab9  #    50  2013-06-07 12:38:20  x86-64, xen, mmu: Provide an early version of write_cr3.
git bisect  bad c47f39e3b75e1138823984ad5079547c7a41b726  #     0  2013-06-07 12:42:40  Merge branch 'x86/microcode' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
git bisect good 0d91ea86a895b911fd7d999acb3f600706d9c8cd  #    50  2013-06-07 13:10:33  x86, doc: Documentation for early microcode loading
git bisect  bad da76f64e7eb28b718501d15c1b79af560b7ca4ea  #     0  2013-06-07 13:10:36  x86/Kconfig: Make early microcode loading a configuration feature
git bisect  bad 1612e111e4e565422242727efb59499cce8738e4  #     0  2013-06-07 13:10:56  Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
git bisect  bad 4e1e7059d375482daeeda395bba2939679b1ee14  #     0  2013-06-07 13:11:11  Add linux-next specific files for 20130606

Thanks,
Fengguang