On Wed, 9 Jan 2008, Marius Groeger wrote: > I'm having problems with qemu's (-M prep, -cpu 604) handling of the > MSR_SE bit. My gdbstub can successfully step along regular code, but > qemu chokes when stepping over a branch instruction like "blr". > (Needless to say, that same gdbstub works fine on real hardware). I > tried older versions of qemu and found that the code base 8 months ago > worked fine.
I have now verified with booting a Linux image into qemu-system-ppc - same problem. When stepi'ing over the following sequence, the system chokes on a "bl" instruction: / # gdb testprg GNU gdb 6.3.50.20050810 Copyright 2004 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "powerpc-linux"...Using host libthread_db library "/lib/libthread_db.so.1". (gdb) b main Breakpoint 1 at 0x10000520: file testprg.c, line 26. (gdb) run Starting program: testprg Breakpoint 1, main () at testprg.c:26 26 testprg.c: No such file or directory. in testprg.c (gdb) disassemble Dump of assembler code for function main: 0x1000050c <main+0>:stwu r1,-32(r1) 0x10000510 <main+4>:mflr r0 0x10000514 <main+8>:stw r31,28(r1) 0x10000518 <main+12>:stw r0,36(r1) 0x1000051c <main+16>:mr r31,r1 0x10000520 <main+20>:lis r9,4096 0x10000524 <main+24>:addi r3,r9,2376 0x10000528 <main+28>:crclr 4*cr1+eq 0x1000052c <main+32>:bl 0x10010ad8 <printf> 0x10000530 <main+36>:lis r9,4096 ... (gdb) stepi 0x10000524 26 in testprg.c (gdb) stepi 0x10000528 26 in testprg.c (gdb) stepi 0x1000052c 26 in testprg.c (gdb) stepi <<< QEMU HANGS! >>> > Any ideas? Did perhaps the PPC440 additions add some regression here? ?! Regards and TIA, Marius -- Marius Groeger <[EMAIL PROTECTED]> SYSGO AG Embedded and Real-Time Software Voice: +49 6136 9948 0 FAX: +49 6136 9948 10 www.sysgo.com | www.elinos.com | www.osek.de | www.pikeos.com