On Wednesday 25 March 2015 17:33:59 Leon Alrae wrote: > On 25/03/2015 15:38, Duarte Silva wrote: > > On Wednesday 25 March 2015 14:54:41 Leon Alrae wrote: > >> On 25/03/2015 14:44, Leon Alrae wrote: > >>> Hi Duarte, > >>> > >>> On 25/03/2015 14:20, Duarte Silva wrote: > >>>> On Wednesday 25 March 2015 13:13:14 James Hogan wrote: > >>>>> Hi Duarte, > >>>>> > >>>>> On 22/03/15 11:13, Duarte Silva wrote: > >>>>>> Hi guys, > >>>>>> > >>>>>> I have been struggling to get some binaries compiled for NetLogic XLP > >>>>>> processor to run under QEMU. I have tried a bunch of things (most > >>>>>> going > >>>>>> back and forth) and always get the following error message: > >>>>>> > >>>>>> qemu: uncaught target signal 4 (Illegal instruction) - core dumped > >>>>>> Illegal instruction > >>>>>> > >>>>>> I tried to debug it using GDB but to no avail. Does anybody have > >>>>>> ideas? > >>>>>> I'm > >>>>>> running QEMU 2.2.1. > >>>>> > >>>>> It sounds like the program had an instruction that QEMU doesn't > >>>>> recognise, or doesn't think should be allowed on the current CPU which > >>>>> you've set with -cpu. You might be able to find out what that > >>>>> > >>>>> instruction is by putting this on your qemu command line: > >>>>> -singlestep -d in_asm > >>>> > >>>> Hi James, > >>>> > >>>> thanks for the help :) I have tried with all the CPU's available. None > >>>> of > >>>> them worked, so I just leave it as undefined. It seems the offending > >>>> instruction is "udi4". > >>>> > >>>> (...) > >>>> IN: > >>>> 0x765d1fa4: udi4 a0,v0,zero,0x0 > >>> > >>> According to this line you are trying to use MIPS32 CPU whereas I > >>> presume you would like MIPS64R2? Please try 5KEf CPU for example which > >>> is available in qemu-mips64 and qemu-mips64el QEMU binaries for big and > >>> little endian respectively. > >> > >> I just noticed the QEMU version you are using and it doesn't contain > >> 5KEf and 5KEc CPUs. Please try MIPS64R2-generic. > >> > >> Leon > > > > Hi Leon, > > > > have a look at the "binary-info.txt" file in the first e-Mail. It does use > > the ELF magic for 32 bits ELF, not the 64 bits, that's why I get the > > following: > > > > # chroot rootfs/ /usr/local/bin/qemu-mips64 -cpu MIPS64R2-generic /bin/sh > > /bin/sh: Invalid ELF image for this architecture > > > > Is there a way to force the execution of the binary even if the flag > > doesn't match? > > > > Also, if you have a look at the flags you get: noreorder, cpic, 32bitmode, > > unknown CPU, o32, mips64r2. So, is it 64 bits or 32 bits ELF file? > > I see, this mips64r2 binary has o32 ABI. It indeed would work in > qemu-mips provided there are no mips64r2-specific instructions. I think > I jumped a bit too quickly to the conclusion. > > QEMU's mips/disas doesn't help much in this case as it just indicates > User Defined Instruction. Presumably this instruction is specific to > this processor and is missing in QEMU. Are you able to get disassembly > of your program and look up what is under 0x765d1fa4 address which > caused the illegal instruction?
Hi Leon, using IDA with a remote debug session to QEMU I got the following disassembly (kept surrounding instructions to give some context). To IDA, this custom instruction is also unknown. MEMORY:765D1F90 sw $v1, 4($v0) MEMORY:765D1F94 addu $a0, $a1 MEMORY:765D1F98 sw $a0, 0($v0) MEMORY:765D1F9C MEMORY:765D1F9C loc_765D1F9C: MEMORY:765D1F9C addiu $a0, $s1, 0x51B0 MEMORY:765D1FA0 move $v0, $zero MEMORY:765D1FA0 # ----------------------- MEMORY:765D1FA4 .byte 0x70 # p MEMORY:765D1FA5 .byte 0x82 # é MEMORY:765D1FA6 .byte 0 MEMORY:765D1FA7 .byte 0x14 MEMORY:765D1FA8 # ----------------------- MEMORY:765D1FA8 slti $v0, 2 MEMORY:765D1FAC beqz $v0, loc_765D204C MEMORY:765D1FB0 nop MEMORY:765D1FB4 lw $ra, 0x24($sp) MEMORY:765D1FB8 MEMORY:765D1FB8 loc_765D1FB8: MEMORY:765D1FB8 move $v0, $s0 MEMORY:765D1FBC lw $s1, 0x20($sp) MEMORY:765D1FC0 lw $s0, 0x1C($sp) Thanks for everything, Duarte > > Leon
