using crash for ARM
 

Hi,
I would like to use crash utility on ARM.
what I understand is there might be two ways to go about it.

1) cross compile whole crash for arm itself, which doesnt seem to be good option because on arm target we will need lots of depedent packages.
2) run crash on x86 and have gdbserver/remoter server compiled on target. and have serial connection and so on..
please suggest instructions or any pointers regarding the same.
Regards,Oza.

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using crash for ARM
 

----- Original Message -----
>
>
>
> Hi,
>
>
> I would like to use crash utility on ARM.
> what I understand is there might be two ways to go about it.
>
> 1) cross compile whole crash for arm itself, which doesnt seem to be
> good option because on arm target we will need lots of depedent
> packages.
>
> 2) run crash on x86 and have gdbserver/remoter server compiled on
> target. and have serial connection and so on..
>
> please suggest instructions or any pointers regarding the same.
>
> Regards,
> Oza.

If you are talking about running crash on a live ARM system, then
option #1 is the only possibility. Option #2 does not exist for
the crash utility; live system access requires either /dev/mem,
/proc/kcore, or the /dev/crash misc driver.

Dave

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using crash for ARM
 

is there any way to pass CC while making as I see configure.c taking care of options.make target=ARM will not help.
I need something like I compile gdb
./configure --host=arm-none-eabi --target=arm-none-eabi

Regards,Oza.

From: Dave Anderson <anderson@redhat.com>
To: paawan oza <paawan1982@yahoo.com>; "Discussion list for crash utility usage, maintenance and development" <crash-utility@redhat.com>
Sent: Monday, 6 August 2012 8:58 PM
Subject: Re: [Crash-utility] using crash for ARM



----- Original Message -----
>
>
>
> Hi,
>
>
> I would like to use crash utility on ARM.
> what I understand is there might be two ways to go about it.
>
> 1) cross compile whole crash for arm itself, which doesnt seem to be
> good option because on arm target we will need lots of depedent
> packages.
>
> 2) run crash on x86 and have gdbserver/remoter server compiled on
> target. and have serial connection and so on..
>
> please suggest instructions or any pointers
regarding the same.
>
> Regards,
> Oza.

If you are talking about running crash on a live ARM system, then
option #1 is the only possibility.* Option #2 does not exist for
the crash utility; live system access requires either /dev/mem,
/proc/kcore, or the /dev/crash misc driver.

Dave



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using crash for ARM
 

Hi Dave,
Will I be able to set breakpoints and watch points in kernel space ?Do you accept the changes/contribution to crash ?

Regards,Oza.
From: Dave Anderson <anderson@redhat.com>
To: paawan oza <paawan1982@yahoo.com>; "Discussion list for crash utility usage, maintenance and development"
<crash-utility@redhat.com>
Sent: Monday, 6 August 2012 8:58 PM
Subject: Re: [Crash-utility] using crash for ARM



----- Original Message -----
>
>
>
> Hi,
>
>
> I would like to use crash utility on ARM.
> what I understand is there might be two ways to go about it.
>
> 1) cross compile whole crash for arm itself, which doesnt seem to be
> good option because on arm target we will need lots of depedent
> packages.
>
> 2) run crash on x86 and have gdbserver/remoter server compiled on
> target. and have serial connection and so on..
>
> please suggest instructions or any pointers regarding the same.
>
> Regards,
> Oza.

If you are talking about running crash on a live ARM system,
then
option #1 is the only possibility.* Option #2 does not exist for
the crash utility; live system access requires either /dev/mem,
/proc/kcore, or the /dev/crash misc driver.

Dave



--
Crash-utility mailing list
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using crash for ARM
 

----- Original Message -----
>
>
> Hi Dave,
>
> Will I be able to set breakpoints and watch points in kernel space ?

Definitely not. Keep in mind that the crash utility is a simple
user-space program that happens to read kernel memory. It is not
a kernel debugger. Setting breakpoints/watch points requires the
capability of modifying kernel memory, setting up kernel handlers
to respond to the breakpoint interrupts, etc.

> Do you accept the changes/contribution to crash ?

Sure -- if you check the archives, you can see that posting patches
is one of the primary purposes for this mailing list.

Dave

> Regards,
> Oza.
>
>
>
>
>
> From: Dave Anderson <anderson@redhat.com>
> To: paawan oza <paawan1982@yahoo.com>; "Discussion list for crash
> utility usage, maintenance and development"
> <crash-utility@redhat.com>
> Sent: Monday, 6 August 2012 8:58 PM
> Subject: Re: [Crash-utility] using crash for ARM
>
>
>
> ----- Original Message -----
> >
> >
> >
> > Hi,
> >
> >
> > I would like to use crash utility on ARM.
> > what I understand is there might be two ways to go about it.
> >
> > 1) cross compile whole crash for arm itself, which doesnt seem to
> > be
> > good option because on arm target we will need lots of depedent
> > packages.
> >
> > 2) run crash on x86 and have gdbserver/remoter server compiled on
> > target. and have serial connection and so on..
> >
> > please suggest instructions or any pointers regarding the same.
> >
> > Regards,
> > Oza.
>
> If you are talking about running crash on a live ARM system, then
> option #1 is the only possibility. Option #2 does not exist for
> the crash utility; live system access requires either /dev/mem,
> /proc/kcore, or the /dev/crash misc driver.
>
> Dave
>
>
>
>

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using crash for ARM
 

----- Original Message -----
>
>
> is there any way to pass CC while making as I see configure.c taking care of options.
> make target=ARM will not help.
>
> I need something like I compile gdb
>
> ./configure --host=arm-none-eabi --target=arm-none-eabi
>
> Regards,
> Oza.

I do not have an ARM machine to test with, but it is my understanding that
if you attempt to build on an ARM host, it should just work by entering
"make" alone, i.e., just like any of the other architectures. In other
words, the --host and --target values should default to the actual host.

Although you haven't stated it specifically, it sounds like you are trying
to build an ARM binary on an x86 or x86_64 host? The problem with that is
that there is currently no capability of changing the host compiler that is
used to build the top-level crash source files. The crash sources themselves
are always compiled using the host's default compiler.

Passing --host and --target args to the gdb build would only address the embedded
gdb module. You could try modifying GDB_TARGET_ARM_ON_X86 or GDB_TARGET_ARM_ON_X86_64
(whichever is appropriate) in configure.c with whatever you want. As they are now,
both #define's presume that the host is either x86 or x86_64, and therefore --host
is not passed:

#define GDB_TARGET_ARM_ON_X86 "GDB_CONF_FLAGS=--target=arm-elf-linux"
#define GDB_TARGET_ARM_ON_X86_64 "GDB_CONF_FLAGS=--target=arm-elf-linux CFLAGS=-m32"

For the crash sources you would have to set things up such that "cc" points to
your cross-compiler. You could try changing the Makefile to assign CC= to your
cross-compiler, and then change all of the "cc" commands to ${CC}.

The ARM developers on this mailing list may have some input on this -- I've added
a few of them to the cc list.

Dave


>
>
>
>
>
> From: Dave Anderson <anderson@redhat.com>
> To: paawan oza <paawan1982@yahoo.com>; "Discussion list for crash
> utility usage, maintenance and development"
> <crash-utility@redhat.com>
> Sent: Monday, 6 August 2012 8:58 PM
> Subject: Re: [Crash-utility] using crash for ARM
>
>
>
> ----- Original Message -----
> >
> >
> >
> > Hi,
> >
> >
> > I would like to use crash utility on ARM.
> > what I understand is there might be two ways to go about it.
> >
> > 1) cross compile whole crash for arm itself, which doesnt seem to
> > be
> > good option because on arm target we will need lots of depedent
> > packages.
> >
> > 2) run crash on x86 and have gdbserver/remoter server compiled on
> > target. and have serial connection and so on..
> >
> > please suggest instructions or any pointers regarding the same.
> >
> > Regards,
> > Oza.
>
> If you are talking about running crash on a live ARM system, then
> option #1 is the only possibility. Option #2 does not exist for
> the crash utility; live system access requires either /dev/mem,
> /proc/kcore, or the /dev/crash misc driver.
>
> Dave
>
>
>
>

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using crash for ARM
 

how about if crash utility supports breakpoints/watchpoints specifically hw level.of course need a kernel module to modify kernel memory as you suggested.
was there any specific reason, you did not support this, thinking already kgdb and kdb types of utility available ?If we support breakpoint./watchpoints in crash, will the crash be able to offer much better than any other kernel debug tools ?
what do you think?

Regards,Oza.

From: Dave Anderson <anderson@redhat.com>
To: paawan oza <paawan1982@yahoo.com>
Cc: "Discussion list for crash utility usage, maintenance and development" <crash-utility@redhat.com>
Sent: Tuesday, 7 August 2012 6:58 PM
Subject: Re: [Crash-utility] using crash for ARM



----- Original Message -----
>
>
> Hi Dave,
>
> Will I be able to set breakpoints and watch points in kernel space ?

Definitely not.* Keep in mind that the crash utility is a simple
user-space program that happens to read kernel memory.* It is not
a kernel debugger.* Setting
breakpoints/watch points requires the
capability of modifying kernel memory, setting up kernel handlers
to respond to the breakpoint interrupts, etc.

> Do you accept the changes/contribution to crash ?

Sure -- if you check the archives, you can see that posting patches
is one of the primary purposes for this mailing list.

Dave

> Regards,
> Oza.
>
>
>
>
>
> From: Dave Anderson <anderson@redhat.com>
> To: paawan oza <paawan1982@yahoo.com>; "Discussion list for crash
> utility usage, maintenance and development"
> <crash-utility@redhat.com>
> Sent: Monday, 6 August 2012 8:58
PM
> Subject: Re: [Crash-utility] using crash for ARM
>
>
>
> ----- Original Message -----
> >
> >
> >
> > Hi,
> >
> >
> > I would like to use crash utility on ARM.
> > what I understand is there might be two ways to go about it.
> >
> > 1) cross compile whole crash for arm itself, which doesnt seem to
> > be
> > good option because on arm target we will need lots of depedent
> > packages.
> >
> > 2) run crash on x86 and have gdbserver/remoter server compiled on
> > target. and have serial connection and so on..
> >
> > please suggest instructions or any pointers regarding the same.
> >
> > Regards,
> > Oza.
>
> If you are talking about running crash on a live ARM system, then
> option #1 is the only
possibility. Option #2 does not exist for
> the crash utility; live system access requires either /dev/mem,
> /proc/kcore, or the /dev/crash misc driver.
>
> Dave
>
>
>
>


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using crash for ARM
 

Hi,I got the crash up on the target but I get following error.
WARNING: kernels compiled by different gcc versions:
* ./vmlinux: (unknown)
* live system kernel: 4.4.3crash: cannot open secondary temporary file
I have taken System.map and vmlinux from the same build path.
Regards,Oza.
From: Dave Anderson <anderson@redhat.com>
To: paawan oza <paawan1982@yahoo.com>; "Discussion list for crash utility usage, maintenance and development" <crash-utility@redhat.com>
Sent: Monday, 6 August 2012 8:58 PM
Subject: Re: [Crash-utility] using crash for ARM



----- Original Message -----
>
>
>
> Hi,
>
>
> I would like to use crash utility on ARM.
> what I understand is there might be two ways to go about it.
>
> 1) cross compile whole crash for arm itself, which doesnt seem to be
> good option because on arm target we will need lots of depedent
> packages.
>
> 2) run crash on x86 and have gdbserver/remoter server compiled on
> target.
and have serial connection and so on..
>
> please suggest instructions or any pointers regarding the same.
>
> Regards,
> Oza.

If you are talking about running crash on a live ARM system, then
option #1 is the only possibility.* Option #2 does not exist for
the crash utility; live system access requires either /dev/mem,
/proc/kcore, or the /dev/crash misc driver.

Dave



--
Crash-utility mailing list
Crash-utility@redhat.com
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using crash for ARM
 

----- Original Message -----
>
>
> how about if crash utility supports breakpoints/watchpoints
> specifically hw level.
> of course need a kernel module to modify kernel memory as you
> suggested.
>
> was there any specific reason, you did not support this, thinking
> already kgdb and kdb types of utility available ?
> If we support breakpoint./watchpoints in crash, will the crash be
> able to offer much better than any other kernel debug tools ?
>
> what do you think?
>

I really don't understand how you expect the crash utility to
accomplish such a feat. If a breakpoint were set, it would
generate an interrupt in the kernel, control would be passed
to an interrupt handler, and any "work" would have to be done
there (within the context of the interrupt handler) since the
crash utility code could not run in user-space.

The crash utility has never done such a thing since its inception
in early UNIX. And yes, kgdb, kdb, kprobes, ftrace, or systemtap
would be more in line with what you're looking for.

Dave

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using crash for ARM
 

----- Original Message -----
>
>
> Hi,
> I got the crash up on the target but I get following error.

Well, that's impressive...

> WARNING: kernels compiled by different gcc versions:
> ./vmlinux: (unknown)
> live system kernel: 4.4.3

That's a harmless warning, but what do these commands show:

$ strings vmlinux | grep "Linux version"

and

$ cat /proc/version

The gcc-related data in those two strings are being compared.

> crash: cannot open secondary temporary file

When do you see that message?

>
> I have taken System.map and vmlinux from the same build path.

The System.map file is not necessary if the vmlinux is the kernel
that the live system is running.

Dave


>
> Regards,
> Oza.
>
>
>
>
>
> From: Dave Anderson <anderson@redhat.com>
> To: paawan oza <paawan1982@yahoo.com>; "Discussion list for crash
> utility usage, maintenance and development"
> <crash-utility@redhat.com>
> Sent: Monday, 6 August 2012 8:58 PM
> Subject: Re: [Crash-utility] using crash for ARM
>
>
>
> ----- Original Message -----
> >
> >
> >
> > Hi,
> >
> >
> > I would like to use crash utility on ARM.
> > what I understand is there might be two ways to go about it.
> >
> > 1) cross compile whole crash for arm itself, which doesnt seem to
> > be
> > good option because on arm target we will need lots of depedent
> > packages.
> >
> > 2) run crash on x86 and have gdbserver/remoter server compiled on
> > target. and have serial connection and so on..
> >
> > please suggest instructions or any pointers regarding the same.
> >
> > Regards,
> > Oza.
>
> If you are talking about running crash on a live ARM system, then
> option #1 is the only possibility. Option #2 does not exist for
> the crash utility; live system access requires either /dev/mem,
> /proc/kcore, or the /dev/crash misc driver.
>
> Dave
>
>
>
>

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