From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [203.10.76.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.ozlabs.org", Issuer "CA Cert Signing Authority" (verified OK)) by bilbo.ozlabs.org (Postfix) with ESMTPS id F15A0B7B63 for ; Wed, 9 Sep 2009 16:27:55 +1000 (EST) Received: from e28smtp01.in.ibm.com (e28smtp01.in.ibm.com [59.145.155.1]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e28smtp01.in.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 09D83DDD0C for ; Wed, 9 Sep 2009 16:27:54 +1000 (EST) Received: from d28relay01.in.ibm.com (d28relay01.in.ibm.com [9.184.220.58]) by e28smtp01.in.ibm.com (8.14.3/8.13.1) with ESMTP id n896Rl3p016422 for ; Wed, 9 Sep 2009 11:57:47 +0530 Received: from d28av01.in.ibm.com (d28av01.in.ibm.com [9.184.220.63]) by d28relay01.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id n896RlAp2076690 for ; Wed, 9 Sep 2009 11:57:47 +0530 Received: from d28av01.in.ibm.com (loopback [127.0.0.1]) by d28av01.in.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id n896Rkvl012541 for ; Wed, 9 Sep 2009 11:57:46 +0530 Message-ID: <4AA74AE2.5090001@in.ibm.com> Date: Wed, 09 Sep 2009 11:57:46 +0530 From: Sachin Sant MIME-Version: 1.0 To: rostedt@goodmis.org Subject: Re: [FTRACE] Enabling function_graph causes OOPS References: <4A5C5D65.3030906@in.ibm.com> <4A76BE81.4080707@in.ibm.com> <1252458303.20985.10.camel@gandalf.stny.rr.com> In-Reply-To: <1252458303.20985.10.camel@gandalf.stny.rr.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Steven Rostedt wrote: > I'm going through old email, and I found this. Do you still see this > error. I don't recall seeing it myself. > I can still recreate this with 31-rc9. When i enable tracing with function_graph i notice the following oops. This happens only once. Later if i try to enable/disable tracing i don't get this oops message. This behavior is observed only with function_graph. Other tracers work fine. Oops: Kernel access of bad area, sig: 11 [#1] SMP NR_CPUS=1024 NUMA pSeries Modules linked in: ipv6 fuse loop dm_mod sr_mod ehea ibmveth sg cdrom sd_mod crc_t10dif ibmvscsic scsi_transport_srp scsi_tgt scsi_mod NIP: c000000000008f30 LR: c000000000008f04 CTR: 80000000000f6d68 REGS: c00000003e98f560 TRAP: 0300 Not tainted (2.6.31-rc9) MSR: 8000000000009032 CR: 24000422 XER: 00000020 DAR: 0000000000000008, DSISR: 0000000040000000 TASK = c00000003e953b20[2483] 'irqbalance' THREAD: c00000003e98c000 CPU: 1 GPR00: c000000000008f04 c00000003e98f7e0 d00000000117ed38 0000000000000000 GPR04: 0000000000000000 0000000066000000 00000000000010bf 0000000000000000 GPR08: 0000000000000000 800000010021bb40 00000000000000ff 800000010021bb60 GPR12: 0000000000000002 c000000001032800 0000000000000000 ffffffffeffdff68 GPR16: 00000fffa39fd6a0 00000fffa39e6c38 c00000003ebe9c38 fffffffffffff000 GPR20: c00000002a6cf980 c00000003e98fdf8 c00000003e98fba8 00000fffa1740000 GPR24: fffffffffffff000 8001000003000000 ffe0000000000000 0000000000000009 GPR28: c00000003db40000 0000000000020000 d00000000117da78 c00000003e98f850 NIP [c000000000008f30] .mod_return_to_handler+0x2c/0x64 LR [c000000000008f04] .mod_return_to_handler+0x0/0x64 Call Trace: [c00000003e98f7e0] [c00000002a6cf980] 0xc00000002a6cf980 (unreliable) [c00000003e98f850] [c000000000008f04] .mod_return_to_handler+0x0/0x64 [c00000003e98f900] [c000000000008f04] .mod_return_to_handler+0x0/0x64 [c00000003e98f9a0] [c000000000008f04] .mod_return_to_handler+0x0/0x64 [c00000003e98fa30] [c000000000008ed0] .return_to_handler+0x0/0x34 (.bad_page_fault+0xc8/0xe8) [c00000003e98fb30] [c000000000008ed0] .return_to_handler+0x0/0x34 (handle_page_fault+0x3c/0x5c) [c00000003e98fc20] [c000000000008ed0] .return_to_handler+0x0/0x34 (.ehea_h_query_ehea_port+0x74/0x9c [ehea]) [c00000003e98fcd0] [c000000000008ed0] .return_to_handler+0x0/0x34 (.ehea_get_stats+0xa0/0x1d0 [ehea]) [c00000003e98fd80] [c000000000008ed0] .return_to_handler+0x0/0x34 (.dev_get_stats+0x50/0xec) [c00000003e98fe30] [c000000000008ed0] .return_to_handler+0x0/0x34 (.dev_seq_show+0x5c/0x140) Instruction dump: 4e800020 f881ffe0 f861ffe8 f841fff0 fbe1fff8 7c3f0b78 f821ff91 3c800000 60840000 788407c6 64840000 60840000 48126375 60000000 7c6803a6 ---[ end trace bb43efc994aed790 ]--- function_graph traces are recorded and can be retrieved using /sys/kernel/debug/tracing/trace. 1) 3.936 us | } 1) | .release_console_sem() { 1) 0.594 us | ._spin_lock_irqsave(); 1) 0.560 us | ._call_console_drivers(); 1) 0.580 us | ._call_console_drivers(); 1) 0.582 us | ._spin_lock_irqsave(); 1) | .up() { 1) 0.592 us | ._spin_lock_irqsave(); 1) 0.556 us | ._spin_unlock_irqrestore(); 1) 2.842 us | } 1) 0.588 us | ._spin_unlock_irqrestore(); 1) 9.750 us | } 1) + 75.274 us | } 1) | .die() { 1) | .oops_enter() { Thanks -Sachin -- --------------------------------- Sachin Sant IBM Linux Technology Center India Systems and Technology Labs Bangalore, India ---------------------------------