Architectures and Processors forum Debug using gdb debugger, how to get the exception level?

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Debug using gdb debugger, how to get the exception level?

Boon Khai over 4 years ago

I'm debugging the ARM Cortex A53 on the QEMU emulator using gdb debugger, any idea on how to get what exception level I'm running on (EL3/2/1/0) ?

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0 vstehle over 4 years ago

In gdb the PSTATE is available as CPSR:

(gdb) info registers
x0             0x1                 1
...
cpsr           0x60000000          [ EL=0 C Z ]
...

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0 vstehle over 4 years ago

In gdb the PSTATE is available as CPSR:

(gdb) info registers
x0             0x1                 1
...
cpsr           0x60000000          [ EL=0 C Z ]
...

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0 Boon Khai over 4 years ago in reply to vstehle

Hi Vstehle,

I'm able to dump out the cpsr register, but I don't have the decoded register value like yours in the square bracket, referring to the document you shared, I don't find any bit specifying the Exception Level, only the NZVC APSR, etc...

Here is my cpsr at EL3 (i guess)

And here is my cpsr at EL0 (i guess, because it is now running the baremetal application)
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+1 vstehle over 4 years ago in reply to Boon Khai

Hi Boon Khai,

gdb gets EL from CPSR bits 3:2.

(See also SPSR_EL1.M[3:2].)

CPSR 0x400003cd has indeed EL == 3,

CPSR 0x60000045 has EL == 1.
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0 Boon Khai over 4 years ago in reply to vstehle

Hi Vstehle,

Got it! Thanks a lot!
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