Greetings, Oops below bisects to.. 4a0b2b4dbe1335b8b9886ba3dc85a145d5d938ed is first bad commit commit 4a0b2b4dbe1335b8b9886ba3dc85a145d5d938ed Author: Andi Kleen Date: Tue Jul 1 18:48:41 2008 +0200 sysdev: Pass the attribute to the low level sysdev show/store function [ 85.792961] BUG: unable to handle kernel NULL pointer dereference at 0000000000000002 [ 85.796503] IP: [] sched_mc_power_savings_store+0x13/0x40 [ 85.796503] PGD 0 [ 85.796503] Oops: 0000 [1] SMP [ 85.796503] CPU 1 [ 85.796503] Modules linked in: ip6t_LOG xt_tcpudp xt_pkttype xt_limit snd_pcm_oss snd_mixer_oss snd_seq snd_seq_device af_packet ip6t_REJECT nf_conntrack_ipv6 ipt_REJECT xt_state iptable_mangle iptable_nat nf_nat iptable_filter ip6table_mangle nf_conntrack_netbios_ns nf_conntrack_ipv4 nf_conntrack ip_tables cpufreq_conservative cpufreq_userspace cpufreq_powersave acpi_cpufreq ip6table_filter ip6_tables x_tables ipv6 microcode nls_iso8859_1 nls_cp437 vfat fat fuse loop dm_mod tda1004x saa7134_dvb videobuf_dvb dvb_core tda827x tda8290 tuner saa7134 ir_common compat_ioctl32 videodev v4l1_compat snd_hda_intel v4l2_common firewire_ohci snd_pcm videobuf_dma_sg videobuf_core firewire_core snd_timer snd_page_alloc tveeprom crc_itu_t i2c_i801 snd_hwdep usb_storage iTCO_wdt sr_mod e1000e snd rtc_cmos cdrom ohci1394 i2c_core iTCO_vendor_support rtc_core ieee1394 button intel_agp sg soundcore rtc_lib usbhid hid ff_memless ehci_hcd uhci_hcd sd_mod usbcore edd ext3 mbcache jbd fan ahci libata scsi_mod dock thermal processor [ 85.796503] Pid: 5514, comm: sched-powersave Not tainted 2.6.27-smp #16 [ 85.796503] RIP: 0010:[] [] sched_mc_power_savings_store+0x13/0x40 [ 85.796503] RSP: 0018:ffff8800a69b7e98 EFLAGS: 00010292 [ 85.796503] RAX: fffffffffffffffb RBX: 0000000000000002 RCX: ffffffffffffffea [ 85.796503] RDX: 0000000000000002 RSI: ffff8800a9c18000 RDI: ffffffff80557f90 [ 85.796503] RBP: ffff8800a69b7ea8 R08: ffffffff8022fe3c R09: ffff8800a9c18000 [ 85.796503] R10: 000000000009f868 R11: 0000000000000001 R12: ffff8800b11cfba0 [ 85.796503] R13: ffff8800bf80b730 R14: 00000000ffffffed R15: ffffffff80557fd8 [ 85.796503] FS: 00007f23d609d6f0(0000) GS:ffff8800bf809480(0000) knlGS:0000000000000000 [ 85.958513] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 85.964251] CR2: 0000000000000002 CR3: 00000000a6947000 CR4: 00000000000006e0 [ 85.968514] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 85.968514] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 85.968514] Process sched-powersave (pid: 5514, threadinfo ffff8800a69b6000, task ffff8800bd426820) [ 85.998516] Stack: ffff8800a69b7ea8 ffffffff80557a10 ffff8800a69b7eb8 ffffffff8037a533 [ 86.006589] ffff8800a69b7f08 ffffffff802d7d19 ffff8800a69b7f48 ffff8800b11cfbc0 [ 86.008516] ffffffff80557a10 0000000000000002 ffff8800a683b600 ffff8800a69b7f48 [ 86.008516] Call Trace: [ 86.008516] [] sysdev_class_store+0x24/0x26 [ 86.008516] [] sysfs_write_file+0xdf/0x114 [ 86.008516] [] vfs_write+0xab/0x105 [ 86.008516] [] sys_write+0x47/0x6f [ 86.008516] [] system_call_after_swapgs+0x7b/0x80 [ 86.008516] [ 86.008516] [ 86.008516] Code: c7 c7 d0 d8 53 80 89 c3 e8 40 07 1f 00 e8 cf 60 00 00 89 d8 5e 5b c9 c3 55 48 89 e5 53 48 89 cb 48 83 ec 08 48 c7 c1 ea ff ff ff <8a> 12 8d 42 d0 3c 01 77 1d 31 c0 80 fa 31 0f 94 c0 89 05 a6 c4 [ 86.008516] RIP [] sched_mc_power_savings_store+0x13/0x40 [ 86.008516] RSP [ 86.008516] CR2: 0000000000000002 [ 86.092212] ---[ end trace 35b0ed9dbfbda663 ]---