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Thank you Mike, Great seminar!

RS232, JTAG, Ethernet -debugging

No use of assembly language

Have used JTAG with an ARM processor.

Iron

we use the jtag all the time

I havent used the GNU debugger

Okay picking up the last lecture

I hope I can get that T-shirt

Iron

I watched the final session this AM. Want to thank Chuck & Mike for a great week!

Iron

Thanks Mike. Very informative session

Iron

What about T-shirt?

Iron

Thanks alot for the presentation Mike.

 

Iron

I have done that with motorolla microcontroller

Iron

No I have not but would like to.

Iron

no I have not used it.

Iron

I am very comfortable with assembly language, I have programmed for Motorolla and also for Intel Architecture. Also C programming for Motorolla.

Iron

I have done some C shell programming

Iron

Thaks Mike. Great job.

Blogger

I have used a jtag for debugging pcbas

Iron

So long everyone.  Have a great weekend.  Time to go get a beer... ;-)

jwessel n mike : Same to you! we are enlightened! from these presentations and chat

jwessel: Actually we met once at LinuxWorld before that confernce went buns up.  But, it's a small community and I'm sure we'll meet in real life again.

Happy debugging to all and to all a SUPER Great weekend.

Iron

Mike, I would not be surprised if at some point we bump into each other in the future or may have even done so in the past.  The embbedded community is still farily small even with the explosive growth in the Android world.

Iron

jwessel n Mike: Thanks so much! great info!

@kernelkernel: I'd say that it's way easier to debug on ARM at early stages than x86.  No real-mode hoops, IDT or GDT crap to jump through.

kernelkernel: I can speak from the angle of the Wind River tools, the answer is yes.  If you have a big pocket book the ARM Real View tools will do "the whole nine yards".

Iron

jwessel: that answered a lot! thanks!

@jwessel: Yeah, I'm sorry to miss the kernel summit.  Too many other things happening this year.

I was wondering when you have to debug at the firmware level when the board is just a baby, then does arm have enough debugging tools like x86?

That was one of the big pushes behind the debug core in the kernel was to allow other archs to fill out a "processor specific stub" + "a polled I/O driver", then you could get a whole debugger working.

Iron

Ahh yes.  EHCI debug adapter.  A very nifty little gizmo.  

@kernelkernel:  actually there are many more for processors other than x86.  x86 is a real pain for JTAG.

kdb / kgdb work on all the most widely use archs, blackfin, x86, mips, arm, sh, ppc and sparc, and few others.

Iron

Are the debuggers mostly avl only for x86 as of now? compared to ARM?

I do have a new set of experiemental patches that I'll be brining to the 2012 kernel summit for KGDB over USB using those cheap $7-15 USB dongles (specifically the FTDI and PL2303 devices).

Iron

@jwessel: Yeah, it's nice to have it in there if you've got a way to interact with the user like on x86.  Tough to do that on a router or printer though.  I'd love to see KGDB over USB or KGDBoE come back.  The Ethernet option was particularly handy because you could have th console and debug at the same time without the interleaving.

You just have to know the little tricks to turn it on.   Another really useful device to have (which time didn't permit for in Mike's presentation) is the EHCI debug adapter, if you are using x86 HW.  If you don't have a serial and don't have a jtag, this device will get you early_printk() as well as kdb / kgdb at 1 mbit speeds.

Iron

yes used JTAG interface for ARM debug

Iron

jwessel: Nice to have you among the audience!

We recommend to customers and even Canonical Ubuntu does this to leave KDB built into the kernel.  It is really nice to be able to catch those super evil panics and simply run dmesg.

Iron

It's a pretty tricky topic to have scattered across 5 days.

Time is abolutely the enemy of course.  I am amazed at how much gound mike covered in the last 5 sessions. :-)

Iron

@jwessel: also thanks for the info that KDB is off by default in mainline.

Chuck, If Digi ever wants to contact me to go even deeper on kgdb / kdb or something like that in the future, I'd be happy to present.   Mike only got to scratch the sufface of some of the power.

 

In the future I am looking to get the USB and perhaps kgdboe back in the kgdb dev branch.  It is now working my local tree against the 3.4 -> linus head branch.

Iron

mike: Thanks very much for the email id!

I can be contacted at mike@theptrgroup.com

@jwessel:  I thought so.  Sorry for not mentioning you by name.  I just get rolling on these presentations and time is always the enemy.

Mike: by any chance do the audience get to share your email id?

Mike.  That is correct.  jwessel = Jason Wessel.

Iron

@jwessel: Weren;t you one of the KGDB lite authors?  Sure, I'd include those links in the material moving forward.  Thanks!

 

Mike: Thanks for this info! Sure will try my best. It would be very enlightening!

@kernelkernel: I'm speaking at both the DesignEast and the ARM Techcon conferences.  Stop by and say hi!

 

Mike n Chuck: Have a great Weekend and get some rest :)

Mike, your presentation materials and content were excellent.  Perhaps you can make the following minor additions in the future.

Kgdb / kdb website:  http://kgdb.wiki.kernel.org/

Kgdb Mailing list: kgdb-bugreport@lists.sourceforge.net


With respect to kdump, don't forget about the decoding tools: http://people.redhat.com/anderson/

Iron

Mike: ahh I see. May be we can get more of your presentations like that at upcomming summits!

Thanks everyone for attending.  Have a great weekend!

Thanks! Again, this series has been very useful. (And the audience has been helpful, too.)

@kernelkernel: yeah, sorry about that.  The recording was done by a third party.

Mike: sure. the quality is not good at either locations :(

@jamesdeutch: Yes, the FS2 can be used for most of the bootloader work that you'd care to do.  On the beagleboard, you can even use it for the xloader.

@Michael:  yes, I recall also seeing OpenOCD and being able to "attach" gdb session via JTAG; the price is right if that fits the bill.  Thanks again.

Iron

Thanks Mike.  Your presentations were very helpful.

Iron

@kernelkernel: That presentation can be found at both the Linux Foundation website (I did it at the Android bulder's summit earlier this year) and at the OpenOCD website.  I didn't do the original recording.  So, I'm afraid I couldn't control the quality :(.

@Mike Do you know if the Flyswatter 2 can be used for bootloader debug?

@gbabecki: The Flyswatter 2 and OpenOCD (w. eclipse plug in) can be pulled together for < $100.  I'd use that.

@timd: if you look at the boot output on the serial console, you'll see a line of output that tells you how much memory the kernel is using.  If you try that from user space, the memory size includes buffers and chaching space as well.  So, you can't tell how much the kernel proper is using.  An you should always beconcerned about memory usage on an embedded platform.

@Michael, thank you very much, I did not know the size of that kmalloc() pool is #defined as opposed to kernel config. I will continue looking. PS. A world reknowned manufacturer could have done a better job differentiating where to use GFP_ATOMIC :|

Iron

@Michael:  re JTAG interface chipset; yes, of course the FTDI USB chipset.  I believe I have seen this in the TinCan and Flyswatter tools on the web.  I'm looking to piece together an Eclipse-based (nominally ARM) based development platform with JTAG debugging, out of my own pocket.  I'm a old UNIX kernel person from my first job at Bell Labs in the late 70's, then transitioned to embedded stuff in the 80's and early 90's.  Doing "system engineering" work now but striving to get back to my first love doing embedded and looking to dig into embedded Linux.  Thanks for the great overview course.

Iron

Mike: could you kindly let us know if you a better version of this presentation:

http://video.linux.com/videos/using-openocd-jtag-in-android-kernel-debugging

@Chuck and DigiKey - bring back the Starbuck's coupon ;^)

Iron

Thanks Mike and Chuck, great job.

Iron

Mike and Chuck, thanks for the interesting week. have a great weekend all.

Iron

@arkamax: you're really talking about the kernel's emergency page pool (GFP_ATOMIC allocates from there).  There's a #define that proovides a guidline for the size of the emergency page pool.  But, at the moment, I can't recall the define's location :(.  However, it's really bad form to use GFP_ATOMIC allocations indescriminantly.  I'd recommend a detailed analisys of the driver to find where they really need ATOMIC vs. the normal GFP_KERNEL allocations and fix the driver.

I have a small embedded system with an ARM processor.  How can I tell how much RAM the kernel is using?  Is there a way to look at this from user-space?  Should I be concerned about my programs using to much RAM?

Iron

Thank you Mike and Chuck for this great series of presentations! They have been very useful.

jaranda: You can debug from power on all the way through the kernel user space depending on the tools.  But certainly you can debug u-boot with a JTAG.  We often refer to working on the boot loader and prior to having a working kernel printk as "board bring up".

Iron

Mike,

just a note some of the books are on Kindle for savings.....  assuming what you watch on doesn't crash with target system.

Iron

Mike, can I debug Uboot with a JTAG?

Iron

Mike: Thanks,  this clarifies every thing

I use JTAG debug every day!

Thanks! Great presentation!

Iron

Kudoes to Micheal, Chuck and Digikey.

Iron

I have the TI Stellaris LM3S811 which can be used as USB to JTAG with several suites -- Code Composer, IAR etc.

Iron

Thank you so much for this series...

 

Iron

Thanks Mike. I'm not a linux developer or user yet, but the ideas for instrumenting the system are really useful for future projects. They may be based on some kind of OS or just a state machine. Software instrumenting using dynamically loaded modules or stubs on the system code sounds good to me.

Iron

@Chuck - thank you and DigiKey for a great week of presentations - look forward to the next session beginning Aug 20th

Iron

@kernelkernel: IP-based JTAGs typically only allow one connection per target baord to keep folks from colliding with each other as they debug.

http://openocd.sourceforge.net/

 

OCD open on-chip  debugger

 

Iron

@Mike - thanks for the great, informative and well organized week of presentations - look forward to having you back on these sessions

Iron

@Michael - yes, I do - there is about 25 places where kmalloc() is used, and the way the source is built, it's hard to understand what's called from where. Is there any way to increase mem pool for kmalloc()? They recommend 4 Mbytes at least. Thanks.

Iron

@gbabeki:  The chipset is the FTDI 232H that is a dual channel USB and JTAG.  It's used on the TinCan Tools Flyswatter 2 JTAG among others.  Really great interface for ARM debugging. 

Thank you for good course.

Iron

Mike: when we use JTAG over ip, then is it time shared?

How are resets affected

thank you michael

 

Iron

I have a small embedded system with an ARM processor.  How can I tell how much RAM the kernel is using?  Is there a way to look at this from user-space?

Iron

Thank you Michael!

Iron

@jamesdeutch Tin Can Tools sells one for the Beagleboard and Pandaboard

http://www.tincantools.com/product.php?productid=16153&cat=251&page=1

Iron

THANKS MIKE. THE INFORMATION IS "WOW" GREAT...

Thanks, Mike!  Great presentation.  Gives me a good overview to try using Linux for development.

Iron

Interesting AND useful -- thanks!

@arkamax: do you have access to the sources for the driver?  GFP_ATOMIC should only be used in allocations from ISR level.

Thanks for this valuable presentation.

Iron

Thanks Michael for sharing your knowledge and experience

Iron

Thank you for the great class.

Iron

thanks guys. have a nice week-end

Iron

@Michael:  I didn't catch the whole statement, but I believe you mentioned something about a "chipset"(?) or a device make makes a decent JTAG interface, particularly ARM-based boards.  Could you repeat what you were referencing. Thanks.

Iron

@Michael Anderson, how can you use the AVR Dragon to debug on the Arduino?. You mentioned arduino, and I've read you have to modifly the board.

Iron

@Mike: Any thoughts or recommendations on an inexpensive JTAG device/environment that works with the BeagleBoard-xM?

Thanks Mike and Chuck.

Iron

Thank you for the course.  It has been very enlightening.

Iron

Many thanks Mike & Chuck - very useful.

Iron

Thank You Mike and Chuck!

Iron

Thanks to all and DigiKey! Even bought some syuff directly related to classes. ;-)

Iron

thanks guys. hugely good week.  well done.

 

Iron

Was great.  Thanks again.

Iron

thanks! very good course 

Iron

thank you for the great classes

Iron

Thanks a lot! Chuck n Mike!

Have a graet weekend!

Analyzed coredumps files and were very helpful

Iron

Speaking of kernel compiling... I've got a third party driver that is overly zealous on kmalloc() with GFP_ATOMIC flag set - it basically runs out of kmalloc()'able default memory pool I have on my ARM. Vendor says I can increase the size of kmalloc() memory pool - but I cannot find how to do that. Using LTIB from Freescale. Any comment helps. Thanks :)

Iron

Thank you for the presentation Michael

Thank you Chuck and Digikey for hosting and sponsoring

Iron

used it for code download and debugging

 

Iron

YESS, openocd is great. Is there a tutorial on it?

Iron

And if you have further questions or comments to about kgdb / kdb please do send them to the mailling list: kgdb-bugreport@lists.sourceforge.net

Iron

TinCan Tools sells a prettly good jtag debugger for the Panda board.

Iron

Thanks Michael & Chuck for a useful week. I plan on referencing this again.

thank you Michael,

Iron

Very nice job,  Well worth the time.  Thanks!

Iron

Thanks, this course was a very good intro.

Iron

Thanks Mike great serries!

Iron

What a great class!  Thanks Mike.  And, Thanks to Digi-Key and Design News.

Iron

Iave Chris Embedded  book, and I like it.

Iron

Thanks much, Michael.

Iron

Chris gave an awesome talk on Yocto in San Antonio on the FTF

 

Iron

"Real Developers use printk"?????  hmmmpphhh!

Real developers use whatever works and have no shame about it!

Iron

also used the lights on the front panel loader to debug/troubleshoot the system. core dump and the "song" played by the lights told a story.

Iron

core dumps are great fun...  fixed many problems, many times with them, extremely valuable

 

Iron

@Chuck - have used memory core dumps extensively (when all else fails) and found most all errors

Iron

The cover on the Robert Love book is outdated

Iron

On Windows x86 core dump is very useful in finding out the bug using WinDBG similar to Linux.

 

Iron

Have done core dumps of actual core (magnetic) memory, on PDP-11

Iron

core dump - was successful. drexel university still teaches this in cs283 & cs 281

Iron

Yes - stack back traces are always useful (form of core dump) have used it to find many defects.

Memory Core dump. Ancient history really -- but yes, and sometimes it even works. Tracing is better if feasible.

Iron

Have used both lkcd and kdump.  Have been able to find the problem.  This is the only way if the system is deployed.

Iron

There was a point when a core dump was all you had...  You used it until you fixed the problem.

Iron

There is no reference to the kdump's user space portion.  You should google for "redhat" "crash".  The crash utility is what you use to get the information out of a kdump.

Iron

Yes done a core dump. Totally unsuccessful at finding the prob.

Iron

Tried, it was frightening.

Gold

have used an actual core dump for debug. real core memory.

Iron

@Chuck - yes, have used the memory dumps for debugging quite successfully

Iron

Never used a memory core dump for debugging the kernel

Iron

Yes, it tells where the process ran off the rails.

Yes with IAR for MSP430 family microcontrollers

Iron

Nope, never used a Linux core dump.

I have, but only to match a knowledge base of core dumps

Iron

@Chuck: yes and yes

Iron

never used a memdump

Iron

Loaded code with JTAG but no debug.

Iron

I used them on the XC16x or XE16x and the Hardware Debugger on several Freescale Processors (called BDM, not JTAG, but has a similar functionality)

Iron

Software folks need to be aware of the voltage of the target and how the JTAG interfaces to it. Some JTAG modules have voltage levelers. Some may require a jumper or switch to adjust.

Iron

Use JTAG frequently for development/debugging.

Iron

Used JTAG for debugging and updating firmware at a company I used to work for.

Iron

JTAG rocks.   Out of a good, better, best, for solving a problem it is the best next to having full trace data or a reverse executing simulator.

Iron

@Chuck - have not use JTAG but plan on doing so

Iron

How do you do the modification on Arduino ONE for DebugWIRE?

or how do I connect the JTAG from the AVR Dragon on arduino

Iron

One time only in a galaxy long ago and far away.

Iron

using JTAG for 7 years

 

Iron

I used one a few years ago.  I really like external pins and a scope since I trust those without the extra processor on top.

Iron

I have been lucky to have ICE when needed, so no jtag yet.

Iron

Yes with IAR embedded workbench & ARM processor

Iron

Daily use USB (Segger) based for ARM devices.

Yes used it especially when bringing up the board or debugging BIOS code.

Iron

Yup all the time with Jlinks, Seggers and Commanders.

Iron

Haven't needed to use JTAG yet

Iron

I have used JTAG, but not on a Linux system.

Iron

Have not used JTAG

Iron

I use JTAG debuggers everyday.

 

Iron

Jtag -- yes. -- Stellaris ICDI.

Iron

Use it for 8-bit AVRs all the time, it's the only option there (along with a few even more primitive types)

Iron

yes, i have used jtag

 

Iron

Many times plus all of the other techniques

Iron

@Chuck - yes, have used JTAG

Iron

Use JTAG with MSP430

Iron

used ICE,JTAG,Logic Analyser

Lost the audio after 2 minute network outage.

Iron

The Wind River "ethernet versions" of JTAG devices actually run Linux these days. :-)

Iron

recommendations on affordable jtag

Iron

I have a 100 MHz Rigol oscilloscope $400 (sorry, Digikey does not carry them).  Great for debugging.

Iron

@Mr.E - lost audio several minutes ago - simple paused/stop the radio streamer then started/play again - recovered to problems

Iron

no issues with audio...

Iron

"PC-based logic analyzers" can be had for less than a $100

Iron

Moving to Serial Wire Debug (6 pin alternative to JTAG)

My audio is gone. Anybody else lost audio?

Iron

All is fair in love, war and processor debugging!

Iron

The problem with ICEs is not so much pins as clock speeds;  attaching an external circuit plays hell with timing

Iron

JTAG is pretty much the only choice for lower end 8-bit controllers like AVR. A snap to use (at least in AVR), much easier to set up and get started with than even GDB.

Iron

sorry, d/a converters on the address bus.

Iron

in one of the presentations earlier this year - presenter introduced the use of simple serial printers as debug tools

Iron

i remember an old debugging vector scope in Byte. it had the address bus split on a pair of a/d converters. x-y scope display draws an signature of where the code is executing. a great  tool to "sniff" the bus.

Iron

 oscillioscope,  IDE specific debugers

Iron

"counting pulses" is much easier with a logic analyzer... measuring pulses - with scope

Iron

Got a scope in my office... as well as some bus capture tools...  have a USB one at home...

Iron

Personally own Scope, logic analyzer and RF Test equipment (Spetrum Analyzers, Sig Gens, Network analyzers) for Hobby use. (definitely was valueable to have designed them in the past :)

Using  a Signature Analyzer can provide much more verbosity.

Iron

Used Oscillioscope yesterday to chase down problem with embedded code for a training course. The code is just wrong. Without oscilloscope almost impossible to find.

Iron

@Chuck: have used gdb in several environments, both interactively as a debug tool and scripted to simulate failures during testing

Iron

used more IDE specific debugers

Iron

Used assy from the 6502 and Z80.

Still use it on DSPs now.

Iron

Usually use target specific Hardware IDE.

Used GDB briefly in the past, but not fluent in it.

Used GDB debugger when used to develop Unix drivers.

Iron

Yes, without success.

Iron

@Chuck - have used gdb extensively

Iron

used gnu debugger some time ago..... I am a neophyte with it.

Iron

@Chuck - yes on gnu debugger

Iron

I have used the GDB debugger for debugging small code.

 

Iron

Very little.  Tried to use GDBserver debugger over ethernet, but was unable to get it to work.

Iron

I've used gdb w/ DDD frontend as well as Eclipse front end...

Iron

I have tried it.

Iron

Yes, at command line and with DDD

Some GDB, also, but not as much as I'd like

Iron

I have not used GNU debugger.

Iron

Yes, have used GDB.

Iron

under *nix it is my goto tool

Iron

GDB? That's the only thing that saves the day, using every day

Iron

gnu debugger plenty of times

Iron

GNU debugger -- yes.

Iron

have not used gnu debugger

Iron

Oops, I'm late for the live session... glad it's not over yet...

Iron

commit bce7f793daec3e65ec5c5705d2457b81fe7b5725
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Sun Jul 13 14:51:29 2008 -0700

    Linux 2.6.26

Iron

I write and/or examine Rabbit (an offshoot of Z80 architecture) fairly frequently working on my own Linux-compatible OS that I wrote.

Iron

Mike, one thing that is not mentioned in the presentation is that KMS (Kernel Mode Setting) support was merged as well.  The means you can take a kernel oops or panic while running on a graphics console and jump to the kdb prompt.   (fully merged in 2010).

Iron

When in time was 2.6.26 released?

use assy. lang. on microcontrollers

Iron

used assembly when porting r/t OS from AMD to HP RISC

Iron

What a firmware curriculum would look like

http://www.eetimes.com/electronics-blogs/industry-comment/4372260/What-a-firmware-curriculum-would-look-like

Iron

Can follow x86, have done a fair amount with HC11. 

Iron

@Chuck: work with Motorola 68000 assembly fairly regularly, x86 occasionally

Iron

have also used assy for minicomputers like Varian 620 family

Iron

I have used assemblers and cross assemblers for x86, 8051, motorola 68000, 6808, 6809, etc, and to date myself Z80.

Iron

I'm dating myself, but when I started, real-time was done in assembly.  Full stop.  Architectures, you name it.

Iron

Don't use it now but used to code BIOS and early device drivers in x86 and PowerPC.  

Iron

I wrote all the code to connect KDB up to the kernel's debug core and am the KDB / KGDB maintainer.  So yes, I am fairly familiar with assembly. :-)

Iron

assembly language for 8-bit processors begining with the old 8080 and CP/M

Iron

sometime have to work with Assemble: ARM, TI, PowerPC

Iron

Use ASM on 8 Bit 8051

Iron

@Chuck - years of mainframe assembly - some x86 based assembly

Iron

when it was needed i learned arm arch asm in a cuople of days and have drawn a flow chart out of

the asm code

8051, c or assembley

 

Iron

Know x86 and ARM assembly language.

I've used many Assy Languages including 386, 8080, 6502 and PIC

Iron

Comfort with Assemby  languages well yeah. Quit counting how many years ago and the CPUS. Latest is ARM and AVR.

Iron

recently graduated UMASS lowell with EET. No assembly language required or taught.

Iron

it has been a long time since I have had to work with assembly language.  I have worked on IBM System/360, 8086, pdp 11, and a few others.  I am confortable with assembly language, just rusty.

Iron

yes, with numerous CPU architectures

Iron

Have worked in assembly on PIC.

Iron

Yes, ARM and a few 8-bit MCU

Iron

assembly on 6502, 6510, 68000, PIC16, HC11, and several others.

Iron

Assembly - used motorola 68K, 8051 and ARM MCUs

Still work in assembly language; have done so for the last 14 years; 8051

Iron

Did Assembly in college, and have barely touched it since.

Iron

have been comfortable with assy for a long time. have used it to write simple h/w and f/w debug routines. I haven't used in recent embedded projects.

Iron

Yes. CPU32, PowerPC, and x86.

Iron

I use assembly in 1802, Z80 series and x86.  I need to learn it for ARM.

Iron

jl "wanted to know if you can go to a new/different memory instruction location and continue exec" A: Sure you can just change the program counter register and continue from anywhere.

Iron

Use assembly language on microcontrollers.

Iron

Yes, 68K, PowerPC, ARM...

Iron

@arcress - got it - modify instruction reg

Iron

used to be good at assembly language - Intel

Iron

I'm comfortable debugging assembly output of C code (panics, oops, etc), but I'm not an assembly programmer

Iron

Comfortable - powerpc

 

Iron

Speak? No. Tried? Plenty of times :)

Iron

No issues with assembly language.

Iron

comfortable with x86 Assembly; looking to learn 64 bit assembler

Iron

a variety - HCS12, Z80, 6800

Iron

I am, I used. PPC, ARM, old 68k

 

Iron

not comfortable with assembly because I have not used it in a long time. I can always pick it up.

Iron

I have used assembly on 8 bit micros.

Iron

I spent a decade as an assembly language system programmer.

Iron

LOVE asm!!!!

X86 & OTHERS

Iron

I haven't done assembler in several years - MIPS was the last architecture I did serious work.

Iron

Comfortable reading X86 assembly

pretty good, but not an expert.  Intel/AMD/Arm

Iron

A bit... IA32 and ARM

Iron

The mainline version of kdb is ALWAYS off by default, and there is zero impact to the runtime performance.

Iron

@jwessel - wanted to know if you can go to a new/different memory instruction location and continue exec

Iron

Use 'rm' to set a new instruction location with KDB.

Iron

jl - answer "can you establish a new instruction location with KDB" - yes if you mm (memory modify) and write in a new instruction op code.

Iron

bph has 3 modes, instruction breakpoint, r/w data access and write access breakpoint.

Iron

@Mike - can you establish a new instruction location with KDB

Iron

For some reason Mike did not include a link over to the kgdb / kdb website: http://kgdb.wiki.kernel.org/

Iron

nikel: kdb uses slightly different commands than gdb

ss = single step for example

Iron

Mike does bph (hw brkpt) trip on speculative accesses, or just real/actual accesses?

Iron

is it safe to assume kdb uses the same commands for stepping?

Iron

looks like old things are new again? KDB has the feel of old-time debug monitors.

Iron

The mainline version of KDB connects to the debug core.  The KGDB / gdbstub connects to that very same debug core.   The configuration is all done through the kgdboc (KGDB Over Console) which is the I/O driver layer.

Iron

kdb does not require kallsysms anymore.  Certainly it is more useful this way, but with an embedded device you do no need it if you don't have space.


You can use kdb to get a backtrace and correlate things with the add2line or an ojbdump --source listing.

Iron

I also used a debug cartridge on the C64 in the 80ies

Iron

Actually KGDB was built on top of KDB core, but the point is they use a common core.

Iron

Used to write and debug using assembly if that counts

Iron

happy friday all from edmonton, ab. better late than never.

Iron

I used sourcer to disassemble various things

Iron

Done pelenty of assembly level debug

Iron

I have if DASM in the 90ies if that count.

Iron

Sure, on a variety of systems.

Iron

Using a disassembler means I am really in deep trouble.  I can program in assembly, but this is backwards and you need to really understand the compiler.

Iron

jl "does KDB generate its own symbolics" Answer:  No kdb uses the kernels kallsyms tables.

Iron

vxWorks and some proprietery symbolic assembly language debuggers.

 

Iron

I haven't used a symbolic disassembler since the Amiga.

Iron

I have not used it but I have seen it and am familiar with assembly language.

Iron

Symbolic dissasembler -- yes some -- mainframes, PC embedded

Iron

I have used Vx Shell a little in the past

 

I've dabbled with KDB

Iron

used VxWorks tgt shell in the past

Iron

I have with VxWorks and old OSes from years ago

Iron

kdb is an assembly-level debugger originally ported from ctkdb.  I have used it some years ago.

 

Iron

@Chuck - have not used VxWorks, but have used PC based disassemblers

Iron

i used vxworks a lot

Iron

Used VxWorks years ago...

 

Iron

KDB = debug monitor

 

Iron

Hi all, from late California

Iron

@Mike - does KDB generate its own symbolics

Iron

@earlmit - what is your retaliation for all the garbage being dumped

Iron

Loud and Clear audio.Greetings from India

Iron

Hello from Sunny SE Lake Simcoe Ontario -- where it's raining.

Iron

hello from Timisoara, Romania

Iron

@earlmit - hard to grow rocks. can you teach me how? :)

@earlmit, When Curiosity landed, did it kill your cat?

Iron

hi, from Richmond, BC

Iron

Hello from Albuquerque.

Iron

Greeting from Mars, Earthlings

Last night your rover dug up my wife's rock garden!!

This means war. Prepare for invasion!!!

Iron

Smoking is bad for Mt. Baker's health

Iron

hi from Chandler, AZ

 

Iron

35 years of experienc? You look good for yur age.

Blogger

Hi from Austin, TX where we have 96 degress right now...

Iron

Ashville NC is safest in the south

Iron

@jl Mt. Baker is smoking up by Bellingham.

Iron

hello from SUNNYNMiami???

@LevitonDave - exploding mountains sounds rahter exciting - when can I come watch

Iron

Good afternoon, everyone!  The session will start in about 2 minutes...

Hello from Wisconsin

 

Iron

@RMRSS - don't have to check for Dallas - remember the tornadoes coming thru and throwing 18 wheelers 80 feet into the air

Iron

Hi from Laguna Beach, 80 and 60% humidity.

Iron

Good afternoon Mike.

Iron

@RMRSS - weatherwise Portland is pretty safe, moving ground or exploding mountains on the other hand :)

Good afternoon folks.

Iron

I don't want to check for homicide safty.

Iron

I spent 58 years in the greater Seattle area

Iron

Pouring in NJ. I caught the last couple of lectures on the archive. Looking forward to a live show today!

Blogger

Hello from (75 degrees overcast) Rochester, NY (according to weather.com safest city in NE weatherwise

http://www.weather.com/news/safest-weather-cities-20120808 (Check your city))

Iron

Hi from Portlandia - Nice and sunny (not always rainy/cloudy in Portland) should get to the mid 80s.

Similar to Olympic Penninsula in weather. Spent 20 yrs in Eastern WA much drier and more extreme temperatures.

Cool damp and misty in southern pennsylvania today.

 

Iron

@jl Only for up to 7 years then retiring back in Washington state on the Olympic Penninsula.

Iron

@Kentj - "crispy fried" to say the least with all the humidity - have you permanently relocated to Richmond

Iron

@jl The more the better.  It was over 100 last week in Houston for the Jr. Olympics. I got crispy fried being from Washington State.

Iron

Hello to all from Chicago.

Blogger

In SE Idaho its 80 and a bit smoky due to the fires.

Iron

@Kentj - it always seems a little cooler on the gulf - will be traveling to Angleton in a few weeks - hope that sends rain to north texas

Iron

@jl It's cooler here too.  Only about 85 today

Iron

hello from hot cool Dallas --- hi today 100F low 73 - oh, a cold front came thru last night

Iron

Hello from Richmond, TX

Iron

Hi from Ottawa, On  - Raining and 66F

Iron

Hi from Washington, DC.  Cloudy and 75F here today.  The session will begin in about 20 minutes...

Buenos dias caballeros, saludos desde Ensenada Baja California México.

Iron

Hello from Sweden.

Iron

Happy FRIDAY  from Sunny Silicon Valley, CA. It's 69 °F and it will get to 89 °F today.

Iron

printf("Hello, World\n"); // from Cleveland Ohio USA

Hello all, from Colorado Springs, CO

Iron

Helllo from Germany...

Iron

Good Morning from Mobile, Al



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