2009-01-27 07:37:43     SIGILL illegal instruction

2009-01-27 07:37:43     SIGILL illegal instruction

D V (ITALY)

Message: 68390   

Hello i m trying to debug an audio driver using KGDBOE on the last  kernel ( svn trunk 7036 ) but i get often SIGILL errors. The assembly seems ok and running without debug the same function works well.

In this way is impossible to complete a debug session.

Can anyone help me to fix this problem?

thanks

emag

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2009-01-27 07:47:26     Re: SIGILL illegal instruction

Robin Getz (UNITED STATES)

Message: 68395   

DV

A reproducable test case is the only way to solve a problem.

We use kgdb all the time and don't see the same issues.

-Robin

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2009-01-28 07:44:21     Re: SIGILL illegal instruction

D V (ITALY)

Message: 68472   

I don't know how to make reproducable it. This happens and i remarked that when i do a Step trace into a function a pointer passed as function parameter is modified. I m trying to recompile the kernel with -O0 but i get errors. How to compile with -O0 only my driver i added in the Makefile in the blackfin/sound dir?

thanks a lot

bye

emag

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2009-01-28 08:09:24     Re: SIGILL illegal instruction

Robin Getz (UNITED STATES)

Message: 68475   

DV:

The kernel (by design) is not able to be compiled with -O0.

-Robin

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2009-01-28 08:17:55     Re: SIGILL illegal instruction

D V (ITALY)

Message: 68476   

It recompiles with -O1 but there is always the same problem: when i step into a function the first parameter passed result changed. Any idea about ?

bye

emag

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2009-01-28 08:34:12     Re: SIGILL illegal instruction

D V (ITALY)

Message: 68478   

i found that when i set the breakpoint using insight+gdb   the instruction associated to the breakpoint is not executed and i need to set the PC back of  an instruction line.

for example:  i set the breakpoint  here:  R0 = [P4 + 0x4]  but it's ignored.

bye

emag

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2009-01-30 03:07:38     Re: SIGILL illegal instruction

D V (ITALY)

Message: 68555   

I setup a breakpoint at 0x00162fb0 and KGBD stopped

8   breakpoint     keep y   0x00162fb0 in bf53x_sport_tx_start at sound/blackfin/bf54x_sport.c:381

But the next step is in the middle of the instruction where stopped

(gdb) where

#0  0x00162fb2 in bf53x_sport_tx_start (sport=0x339fcbc) at sound/blackfin/bf54x_sport.c:381

This is the code

    0x162fac    <bf53x_sport_tx_start+4>:        LINK 0xc;        /* (12) */

    379        unsigned flags;

    380  

    381        if (sport->tx_run)

    0x162fb0    <bf53x_sport_tx_start+8>:        R0 = B[P4 + 0x38] (X);

    0x162fb4    <bf53x_sport_tx_start+12>:       CC = !BITTST (R0, 0x1);        /* bit  1 */

The PC is

(gdb) print $pc

$1 = (void (*)()) 0x162fb2 <bf53x_sport_tx_start+10>

0x162fb2 and not 0x162fb4 or 0x162fb0

HELP

thanks