On Mon, Jan 20, 2014 at 7:38 PM, Benoit Pradelle <benoit.pradelle@xxxxxxx> wrote: > Hi all, > > On Linux 3.12.6 over an Intel x86 processor (with intel_pstate=disable), I > am trying to change the frequency with the following command sequence: > > echo "userspace" | tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor > echo "3000000" | tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_setspeed > > It used to work well on older kernels, but since a recent (unknown) kernel > version, the last command occasionaly never returns but I got the following > log: > > [344746.428121] ------------[ cut here ]------------ > [344746.428132] WARNING: CPU: 7 PID: 1882 at > /build/linux-xS3nxO/linux-3.12.6/drivers/cpufreq/cpufreq_governor.c:203 > cpufreq_governor_dbs+0x6a2/0x710() > [344746.428134] Modules linked in: msr cpufreq_userspace nfsv3 parport_pc > ppdev lp parport bnep rfcomm bluetooth ip6table_filter ip6_tables > iptable_filter ip_tables x_tables autofs4 tun pci_stub vboxpci(O) > vboxnetadp(O) vboxnetflt(O) vboxdrv(O) binfmt_misc uinput nfsd auth_rpcgss > oid_registry nfs_acl nfs lockd fscache sunrpc fuse loop joydev hid_generic > usbhid hid snd_hda_codec_hdmi x86_pkg_temp_thermal snd_hda_codec_realtek > snd_hda_intel snd_hda_codec intel_powerclamp snd_hwdep coretemp kvm_intel > kvm crc32_pclmul nvidia(PO) snd_pcm iTCO_wdt iTCO_vendor_support > snd_page_alloc crc32c_intel ghash_clmulni_intel hp_wmi sparse_keymap evdev > rfkill acpi_cpufreq processor psmouse snd_seq snd_seq_device snd_timer snd > mei_me aesni_intel wmi pcspkr i2c_i801 serio_raw aes_x86_64 ablk_helper > cryptd lrw gf128mul soundcore mei glue_helper lpc_ich mfd_core i2c_core > button ext4 crc16 mbcache jbd2 sg sd_mod sr_mod crc_t10dif crct10dif_common > cdrom xhci_hcd ahci libahci ehci_pci ehci_hcd libata scsi_mod e1000e usbcore > usb_common ptp pps_core thermal fan thermal_sys > [344746.428213] CPU: 7 PID: 1882 Comm: tee Tainted: P O > 3.12-1-amd64 #1 Debian 3.12.6-2 > [344746.428215] Hardware name: Hewlett-Packard HP Z220 CMT Workstation/1790, > BIOS K51 v01.14 09/27/2012 > [344746.428217] 0000000000000009 ffffffff8148c9d5 0000000000000000 > ffffffff8105b572 > [344746.428221] 0000000000000000 ffff880037046a00 0000000000000007 > 0000000000000002 > [344746.428224] ffffffff81881fe0 ffffffff81376732 ffffffff8148f559 > ffff88033449dd00 > [344746.428228] Call Trace: > [344746.428237] [<ffffffff8148c9d5>] ? dump_stack+0x41/0x51 > [344746.428245] [<ffffffff8105b572>] ? warn_slowpath_common+0x72/0x90 > [344746.428248] [<ffffffff81376732>] ? cpufreq_governor_dbs+0x6a2/0x710 > [344746.428253] [<ffffffff8148f559>] ? mutex_lock+0x9/0x30 > [344746.428261] [<ffffffffa02d600f>] ? > acpi_processor_ppc_notifier+0xc0/0xc4 [processor] > [344746.428267] [<ffffffff81495c64>] ? notifier_call_chain+0x44/0x70 > [344746.428274] [<ffffffff81372b84>] ? __cpufreq_governor+0xf4/0x280 > [344746.428277] [<ffffffff81373b59>] ? __cpufreq_set_policy+0x129/0x1f0 > [344746.428280] [<ffffffff81373fa5>] ? store_scaling_governor+0xd5/0x1e0 > [344746.428284] [<ffffffff81373d30>] ? cpufreq_update_policy+0x110/0x110 > [344746.428287] [<ffffffff81373902>] ? store+0x72/0xb0 > [344746.428292] [<ffffffff811deba9>] ? sysfs_write_file+0xb9/0x140 > [344746.428297] [<ffffffff81173113>] ? vfs_write+0xb3/0x1e0 > [344746.428301] [<ffffffff81173b23>] ? SyS_write+0x43/0xa0 > [344746.428305] [<ffffffff81499b39>] ? system_call_fastpath+0x16/0x1b > [344746.428307] ---[ end trace 42394bba698a65fd ]--- > [344746.428314] BUG: unable to handle kernel NULL pointer dereference at > (null) > [344746.428317] IP: [<ffffffff813760df>] cpufreq_governor_dbs+0x4f/0x710 > [344746.428321] PGD 3be4fe067 PUD 35dc6a067 PMD 0 > [344746.428325] Oops: 0000 [#1] SMP > [344746.428327] Modules linked in: msr cpufreq_userspace nfsv3 parport_pc > ppdev lp parport bnep rfcomm bluetooth ip6table_filter ip6_tables > iptable_filter ip_tables x_tables autofs4 tun pci_stub vboxpci(O) > vboxnetadp(O) vboxnetflt(O) vboxdrv(O) binfmt_misc uinput nfsd auth_rpcgss > oid_registry nfs_acl nfs lockd fscache sunrpc fuse loop joydev hid_generic > usbhid hid snd_hda_codec_hdmi x86_pkg_temp_thermal snd_hda_codec_realtek > snd_hda_intel snd_hda_codec intel_powerclamp snd_hwdep coretemp kvm_intel > kvm crc32_pclmul nvidia(PO) snd_pcm iTCO_wdt iTCO_vendor_support > snd_page_alloc crc32c_intel ghash_clmulni_intel hp_wmi sparse_keymap evdev > rfkill acpi_cpufreq processor psmouse snd_seq snd_seq_device snd_timer snd > mei_me aesni_intel wmi pcspkr i2c_i801 serio_raw aes_x86_64 ablk_helper > cryptd lrw gf128mul soundcore mei glue_helper lpc_ich mfd_core i2c_core > button ext4 crc16 mbcache jbd2 sg sd_mod sr_mod crc_t10dif crct10dif_common > cdrom xhci_hcd ahci libahci ehci_pci ehci_hcd libata scsi_mod e1000e usbcore > usb_common ptp pps_core thermal fan thermal_sys > [344746.428386] CPU: 7 PID: 1882 Comm: tee Tainted: P W O > 3.12-1-amd64 #1 Debian 3.12.6-2 > [344746.428388] Hardware name: Hewlett-Packard HP Z220 CMT Workstation/1790, > BIOS K51 v01.14 09/27/2012 > [344746.428390] task: ffff8803a3f03080 ti: ffff88033449c000 task.ti: > ffff88033449c000 > [344746.428391] RIP: 0010:[<ffffffff813760df>] [<ffffffff813760df>] > cpufreq_governor_dbs+0x4f/0x710 > [344746.428395] RSP: 0018:ffff88033449dc50 EFLAGS: 00010293 > [344746.428397] RAX: 0000000000000024 RBX: 0000000000000000 RCX: > 0000000000000006 > [344746.428398] RDX: 0000000000000007 RSI: 0000000000000000 RDI: > 0000000000000009 > [344746.428400] RBP: ffff880037046a00 R08: 000000000000000a R09: > 0000000000000376 > [344746.428402] R10: 0000000000000000 R11: ffff88033449d986 R12: > 0000000000000007 > [344746.428403] R13: 0000000000000002 R14: ffffffff81881fe0 R15: > ffff88040cba16d8 > [344746.428406] FS: 00007f4067ae6700(0000) GS:ffff88041ddc0000(0000) > knlGS:0000000000000000 > [344746.428407] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [344746.428409] CR2: 0000000000000000 CR3: 000000035dc7d000 CR4: > 00000000001407e0 > [344746.428411] Stack: > [344746.428412] ffffffff8148f559 ffff88033449dd00 ffffffffa02d600f > 00000000fffffffe > [344746.428415] ffffffff81495c64 ffffffff81881be0 0000000000000000 > ffff880037046a00 > [344746.428419] 0000000000000002 ffffffff81881d00 ffff8803df64b000 > 000000000000000a > [344746.428422] Call Trace: > [344746.428425] [<ffffffff8148f559>] ? mutex_lock+0x9/0x30 > [344746.428432] [<ffffffffa02d600f>] ? > acpi_processor_ppc_notifier+0xc0/0xc4 [processor] > [344746.428436] [<ffffffff81495c64>] ? notifier_call_chain+0x44/0x70 > [344746.428440] [<ffffffff81372b84>] ? __cpufreq_governor+0xf4/0x280 > [344746.428443] [<ffffffff81373b59>] ? __cpufreq_set_policy+0x129/0x1f0 > [344746.428446] [<ffffffff81373fa5>] ? store_scaling_governor+0xd5/0x1e0 > [344746.428449] [<ffffffff81373d30>] ? cpufreq_update_policy+0x110/0x110 > [344746.428452] [<ffffffff81373902>] ? store+0x72/0xb0 > [344746.428456] [<ffffffff811deba9>] ? sysfs_write_file+0xb9/0x140 > [344746.428459] [<ffffffff81173113>] ? vfs_write+0xb3/0x1e0 > [344746.428463] [<ffffffff81173b23>] ? SyS_write+0x43/0xa0 > [344746.428466] [<ffffffff81499b39>] ? system_call_fastpath+0x16/0x1b > [344746.428468] Code: c0 0f 84 55 02 00 00 48 8b 9d b0 00 00 00 48 85 db 0f > 84 4c 06 00 00 41 83 fd 04 0f 84 7b 02 00 00 41 83 fd 05 0f 84 41 02 00 00 > <48> 8b 03 44 89 e7 ff 50 20 48 89 44 24 08 48 8b 03 83 38 01 0f > [344746.428500] RIP [<ffffffff813760df>] cpufreq_governor_dbs+0x4f/0x710 > [344746.428503] RSP <ffff88033449dc50> > [344746.428504] CR2: 0000000000000000 > [344746.428507] ---[ end trace 42394bba698a65fe ]--- > > Can anyone help with that? Can you confirm if you see the same on latest kernel as well? i.e. 3.13. -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
