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diff --git a/doc/src/uml-stack-trace.html b/doc/src/uml-stack-trace.html deleted file mode 100644 index 1b08ed7d1..000000000 --- a/doc/src/uml-stack-trace.html +++ /dev/null @@ -1,129 +0,0 @@ -<PRE> -To: Michael Richardson <mcr@sandelman.ottawa.on.ca> -Cc: user-mode-linux-devel@lists.sourceforge.net -From: Jeff Dike <jdike@karaya.com> -Subject: [uml-devel] Re: stack trace -Date: Mon, 16 Sep 2002 22:36:06 -0500 - -mcr@sandelman.ottawa.on.ca said: -> Can you post (on list or web site) a "script" output of you trying to -> get the right stack out of a stuck uml (tracing myself)...? - -Yup. Here we go... - -Here, I attach to the tracing thread and get the stack of the current thread, -which happens to be the idle thread. - -um 1013: gdb linux 14936 -GNU gdb 5.0rh-5 Red Hat Linux 7.1 -Copyright 2001 Free Software Foundation, Inc. -GDB is free software, covered by the GNU General Public License, and you are -welcome to change it and/or distribute copies of it under certain conditions. -Type "show copying" to see the conditions. -There is absolutely no warranty for GDB. Type "show warranty" for details. -This GDB was configured as "i386-redhat-linux"... -/home/jdike/linux/2.4/um/14936: No such file or directory. -Attaching to program: /home/jdike/linux/2.4/um/linux, process 14936 -0xa014efe9 in __wait4 () - -# This is how you get the current task in the tracing thread - get_current() -# only works in a kernel thread. -(gdb) p (struct task_struct *)cpu_tasks[0].task -$2 = (struct task_struct *) 0xa01c0000 - -# Get the host pid of that task. -(gdb) p $2.thread.extern_pid -$3 = 14939 - -# Get the current ip and sp. -(gdb) shell cat /proc/14939/stat -14939 (linux) T 14936 14936 883 34816 14936 64 5 3 806 7 62 12 0 0 9 0 0 2 -588043 142770176 5008 4294967295 2684358656 2686348640 3221223520 2686205764 - sp ^^^^^^^^^^ - 2685727185 73728 201392128 167776768 268444672 3222308129 0 0 17 0 -ip ^^^^^^^^^^ - -# the sp and ip are items 4 and 5 after the 4294967295 (on 2.2 hosts, that's -2^31 - 1 rather than 2^32 - 1). - -(gdb) p/x 2686205764 -$4 = 0xa01c3f44 -(gdb) p/x 2685727185 -$5 = 0xa014f1d1 - -# Where's the ip? -(gdb) i sym 0xa014f1d1 -nanosleep + 17 in section .text - -# look at the stack around the sp -(gdb) x/32x 0xa01c3f30 -0xa01c3f30 : 0x00000000 0x00000000 0xa01c3f60 0xa00020a8 -0xa01c3f40 : 0x00000004 0xa012e891 0xa01c3f58 0xa01c3f58 -0xa01c3f50 : 0xa01c3f70 0xa0023667 0x00000009 0x3b023380 -0xa01c3f60 : 0xa01c3fa0 0xa012a21d 0x0000000a 0xa01c0000 -0xa01c3f70 : 0xa01c3fa0 0xa012a213 0x00000003 0x00000024 -0xa01c3f80 : 0xa01c3fa0 0xa0011bc4 0xa012b25c 0x00000000 -0xa01c3f90 : 0xa01c3fb0 0x00000000 0xa01c3ffc 0x0000000d -0xa01c3fa0 : 0xa01c3fb0 0xa000c50e 0xa01812e0 0xa01c3ffc - -# The trick here is to locate a frame near the current sp. You're looking -# for a consecutive pair of longwords (fp, ip) having the properties that: -# fp is on the current kernel stack and points further up it -# ip is a text address (if you can't recognize a UML text address by -# sight, print out &_stext and &_etext) -# -# Starting at 0xa01c3f44, the first pair of works satisfying these requirements -# is at 0xa01c3f50. -# So, print that pair out as hex. -(gdb) p/x *((int (*)[2])0xa01c3f50) -$9 = {0xa01c3f70, 0xa0023667} - -# Now, we start climbing the stack. -(gdb) p/x *((int (*)[2])$[0]) -$10 = {0xa01c3fa0, 0xa012a213} -(gdb) -$11 = {0xa01c3fb0, 0xa000c50e} -(gdb) -$12 = {0xa01c3fc0, 0xa000356d} -(gdb) -$13 = {0xa01c3fd0, 0xa013082f} -(gdb) -$14 = {0xa01c3ff0, 0xa012fbdd} -# Stop when you see a NULL frame pointer or gdb bitches at you. -(gdb) -$15 = {0x0, 0xa01513aa} - -# Now we get the symbolic version of the stack with 'i sym' of the second item -# in each pair. -(gdb) i sym 0xa0023667 -check_pgt_cache + 23 in section .text -(gdb) i sym 0xa012a213 -cpu_idle + 123 in section .text -(gdb) i sym 0xa000c50e -rest_init + 46 in section .text -(gdb) i sym 0xa000356d -start_kernel + 361 in section .text.init -(gdb) i sym 0xa013082f -start_kernel_proc + 63 in section .text -(gdb) i sym 0xa012fbdd -signal_tramp + 209 in section .text -(gdb) i sym 0xa01513aa -thread_start + 4 in section .text - -# You can also get line number information with 'i line'. -(gdb) i line *0xa012a213 -Line 488 of "process_kern.c" starts at address 0xa012a213 <cpu_idle+123> - and ends at 0xa012a21d <cpu_idle+133>. -(gdb) - - -------------------------------------------------------- -Sponsored by: AMD - Your access to the experts on Hammer Technology! -Open Source & Linux Developers, register now for the AMD Developer -Symposium. Code: EX8664 http://www.developwithamd.com/developerlab -_______________________________________________ -User-mode-linux-devel mailing list -User-mode-linux-devel@lists.sourceforge.net -https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel - -</PRE>
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