From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from woody.fsl.noaa.gov (woody.fsl.noaa.gov [127.0.0.1]) by woody.fsl.noaa.gov (8.12.5/8.12.5) with ESMTP id gA8KXkbl026967 for ; Fri, 8 Nov 2002 13:33:46 -0700 Received: (from tierney@localhost) by woody.fsl.noaa.gov (8.12.5/8.12.5/Submit) id gA8KXkuA026965 for linux-mm@kvack.org; Fri, 8 Nov 2002 13:33:46 -0700 Date: Fri, 8 Nov 2002 13:33:46 -0700 From: Craig Tierney Subject: Null pointer dereference, mprotect.c, linux-2.4.18 Message-ID: <20021108203346.GA26955@hpti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: owner-linux-mm@kvack.org Return-Path: To: linux-mm@kvack.org List-ID: I am having a problem on my machines. Occasionally on a node the kernel will report: "Unable to handle kernel NULL pointer dereference" The problem always starts in either sys_mprotect or mprotect_fixup_start. It happens more on some nodes than others, but I cannot figure out what activity might cause it to happen more. Kernel: 2.4.18 + trond's nfs patches Node: P4 Xeon 2.2 Ghz 2way SMP 1 GB ram Myrinet Ksymoops output: ksymoops 2.4.5 on i686 2.4.18nfs. Options used -V (default) -k /proc/ksyms (default) -l /proc/modules (default) -o /lib/modules/2.4.18nfs/ (default) -m /boot/System.map-2.4.18nfs (default) Warning: You did not tell me where to find symbol information. I will assume that the log matches the kernel and modules that are running right now and I'll use the default options above for symbol resolution. If the current kernel and/or modules do not match the log, you can get more accurate output by telling me the kernel version and where to find map, modules, ksyms etc. ksymoops -h explains the options. Nov 8 05:01:00 g0062 kernel: Unable to handle kernel NULL pointer dereference at virtual address 0000000a Nov 8 05:01:00 g0062 kernel: c013501f Nov 8 05:01:00 g0062 kernel: *pde = 00000000 Nov 8 05:01:00 g0062 kernel: Oops: 0000 Nov 8 05:01:00 g0062 kernel: CPU: 1 Nov 8 05:01:00 g0062 kernel: EIP: 0010:[mprotect_fixup_start+15/320] Tainted: P Nov 8 05:01:00 g0062 kernel: EIP: 0010:[] Tainted: P Using defaults from ksymoops -t elf32-i386 -a i386 Nov 8 05:01:00 g0062 kernel: EFLAGS: 00010296 Nov 8 05:01:00 g0062 kernel: eax: 0000000a ebx: 40000000 ecx: 0000000a edx: f6494730 Nov 8 05:01:00 g0062 kernel: esi: 0000000a edi: 00000016 ebp: f6494730 esp: e0689e5c Nov 8 05:01:00 g0062 kernel: ds: 0018 es: 0018 ss: 0018 Nov 8 05:01:00 g0062 kernel: Process grep (pid: 4929, stackpage=e0689000) Nov 8 05:01:00 g0062 kernel: Stack: 00000018 00000018 40000000 0000000a 00000016 f7f26158 c0132b14 f6494730 Nov 8 05:01:00 g0062 kernel: 0000000a f7f26158 00000016 f6494680 f6494730 e9a1fc00 eeabf080 f5fecd80 Nov 8 05:01:00 g0062 kernel: 00000000 e9fdd028 c012e490 f5fecd80 4000a000 00000000 c012dd37 f5fec480 Nov 8 05:01:00 g0062 kernel: Call Trace: [filemap_nopage+196/560] [do_no_page+128/576] [do_wp_page+247/736] [handle_ mm_fault+129/288] [do_page_fault+412/1384] Nov 8 05:01:00 g0062 kernel: Call Trace: [] [] [] [] [] Nov 8 05:01:00 g0062 kernel: [] [] [] Nov 8 05:01:00 g0062 kernel: Code: 8b 10 89 28 85 d2 74 0c 8b 45 04 39 42 08 0f 84 c5 00 00 00 >>EIP; c013501f <===== >>ebx; 40000000 Before first symbol >>edx; f6494730 <_end+360c05f4/384aeec4> >>ebp; f6494730 <_end+360c05f4/384aeec4> >>esp; e0689e5c <_end+202b5d20/384aeec4> Trace; c0132b14 Trace; c012e490 Trace; c012dd37 Trace; c012e6d1 Trace; c01193dc Trace; c0105ee2 Trace; c0119240 Trace; c010795c Code; c013501f 00000000 <_EIP>: Code; c013501f <===== 0: 8b 10 mov (%eax),%edx <===== Code; c0135021 2: 89 28 mov %ebp,(%eax) Code; c0135023 4: 85 d2 test %edx,%edx Code; c0135025 6: 74 0c je 14 <_EIP+0x14> c0135033 Code; c0135027 8: 8b 45 04 mov 0x4(%ebp),%eax Code; c013502a b: 39 42 08 cmp %eax,0x8(%edx) Code; c013502d e: 0f 84 c5 00 00 00 je d9 <_EIP+0xd9> c01350f8 Nov 8 05:01:00 g0062 kernel: <1>Unable to handle kernel NULL pointer dereference at virtual address 0000007d Nov 8 05:01:00 g0062 kernel: c0134ce0 Nov 8 05:01:00 g0062 kernel: *pde = 00000000 Nov 8 05:01:00 g0062 kernel: Oops: 0002 Nov 8 05:01:00 g0062 kernel: CPU: 1 Nov 8 05:01:00 g0062 kernel: EIP: 0010:[sys_mprotect+0/608] Tainted: P Nov 8 05:01:00 g0062 kernel: EIP: 0010:[] Tainted: P Nov 8 05:01:00 g0062 kernel: EFLAGS: 00010287 Nov 8 05:01:00 g0062 kernel: eax: 0000007d ebx: f67a0000 ecx: 00008be8 edx: 00000018 Nov 8 05:01:00 g0062 kernel: esi: 40022000 edi: 00133000 ebp: bfffee44 esp: f67a1fc0 Nov 8 05:01:00 g0062 kernel: ds: 0018 es: 0018 ss: 0018 Nov 8 05:01:00 g0062 kernel: Process which (pid: 4932, stackpage=f67a1000) Nov 8 05:01:00 g0062 kernel: Stack: c010786b 40155000 00008be8 00000000 40022000 00133000 bfffee44 0000007d Nov 8 05:01:00 g0062 kernel: 0000002b 0000002b 0000007d 400129d4 00000023 00000206 bfffecb4 0000002b Nov 8 05:01:00 g0062 kernel: Call Trace: [system_call+51/56] Nov 8 05:01:00 g0062 kernel: Call Trace: [] Nov 8 05:01:00 g0062 kernel: Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >>EIP; c0134ce0 <===== >>ebx; f67a0000 <_end+363cbec4/384aeec4> >>ecx; 00008be8 Before first symbol >>esi; 40022000 Before first symbol >>edi; 00133000 Before first symbol >>ebp; bfffee44 Before first symbol >>esp; f67a1fc0 <_end+363cde84/384aeec4> Trace; c010786b Code; c0134ce0 00000000 <_EIP>: Thanks, Craig -- Craig Tierney (ctierney@hpti.com) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/