From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.5) Gecko/20041107 Firefox/1.0 Description of problem: Oprofile doesn't work at all. Version-Release number of selected component (if applicable): vmlinuz-2.6.10-1.1110_FC4 How reproducible: Always Steps to Reproduce: # cat /dev/oprofile/cpu_type Segmentation fault Additional info: # cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 15 model : 5 model name : AMD Opteron(tm) Processor 144 # uname -a Linux zapata.pink 2.6.10-1.1110_FC4 #1 Tue Jan 25 20:28:22 EST 2005 i686 athlon i386 GNU/Linux
oprofile-devel-0.8.1-11 oprofile-0.8.1-11
Here's the kernel trace: <1>Unable to handle kernel NULL pointer dereference at virtual address 00000000 printing eip: f8aec419 *pde = 00000000 Oops: 0000 [#45] DEBUG_PAGEALLOC Modules linked in: oprofile md5 ipv6 parport_pc lp parport autofs4 sunrpc dm_mod video button battery ac ohci1394 ieee1394 ohci_hcd ehci_hcd i2c_nforce2 i2c_core snd_intel8x0 snd_ac97_codec snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd soundcore snd_page_alloc 8139too mii floppy ext3 jbd CPU: 0 EIP: 0060:[<f8aec419>] Not tainted VLI EFLAGS: 00010246 (2.6.10-1.1110_FC4) EIP is at oprofilefs_str_to_user+0x17/0x36 [oprofile] eax: 00000000 ebx: 00000000 ecx: ffffffff edx: ffffffff esi: 00001000 edi: 00000000 ebp: 095de950 esp: c54ccf6c ds: 007b es: 007b ss: 0068 Process cat (pid: 29001, threadinfo=c54cc000 task=e00fda80) Stack: 00000000 f8aefae0 d68bcf58 00001000 c54ccfac f8aec275 c54ccfac c015fd4b c54ccfac 095de950 d68bcf58 fffffff7 00001000 c54cc000 c015ffc0 c54ccfac 00000000 00000000 00000000 00000003 0804b38b c010338b 00000003 095de950 Call Trace: [<f8aec275>] cpu_type_read+0xe/0x10 [oprofile] [<c015fd4b>] vfs_read+0xba/0x115 [<c015ffc0>] sys_read+0x3c/0x62 [<c010338b>] syscall_call+0x7/0xb Code: 8b 53 58 89 43 4c 89 53 50 89 43 44 89 53 48 89 d8 5b 5e c3 55 89 d5 83 ca ff 57 89 c7 56 89 ce 89 d1 53 53 31 db 89 04 24 89 d8 <f2> ae f7 d1 49 51 89 f2 89 e8 ff 74 24 04 8b 4c 24 20 e8 d7 92
Unfortunately, I don't have 32-bit linux installed on a x86-64 machine, so I tried to replicate the problem on 64-bit version. I installed the 64-bit 2.6.10-1.1110_FC4, rebooted the amd64 machine. $ uname -a Linux dhcp59-190.rdu.redhat.com 2.6.10-1.1110_FC4 #1 Tue Jan 25 20:26:47 EST 2005 x86_64 x86_64 x86_64 GNU/Linux $opcontrol --init $ cat /dev/oprofile/cpu_type x86-64/hammer It didn't crash, so this problem seems to be limited to the 32-bit kernels on x86-64 processors. Is there the same problem reading out any of the other files in /dev/oprofile?
zapata:/local/home/aph # cat /dev/oprofile/stats/cpu0/backtrace_aborted 0 zapata:/local/home/aph # cat /dev/oprofile/stats/cpu0/sample_lost_overflow 0 zapata:/local/home/aph # cat /dev/oprofile/stats/cpu0/sample_received 0 zapata:/local/home/aph # cat /dev/oprofile/cpu_type Segmentation fault zapata:/local/home/aph # cat /dev/oprofile/pointer_size 4 zapata:/local/home/aph # cat /dev/oprofile/enable 0
I was able to recreate this with vmlinuz-2.6.10-1.1110_FC4 with an i686 install on the x86-64. However, this problem does not appear on the 2.6.10-1.1134_FC4 version of the kernel. Suggest moving to a newer rawhide kernel.
I can confirm that 2.6.10-1.1134_FC4 fixes the problem. Thanks for your help.