Works Like a charm....The memory at that place was indeed not allocated. Thanks for your help.
Regards, Gauresh Rane Grad Student CS Department UCLA ----- Original Message ----- From: "Peter Maydell" <peter.mayd...@linaro.org> To: "Max Filippov" <jcmvb...@gmail.com> Cc: "Gauresh Rane" <gdr...@cs.ucla.edu>, qemu-devel@nongnu.org Sent: Friday, November 25, 2011 7:40:52 AM Subject: Re: [Qemu-devel] Problem with translating on ARM and Qemu beginner question On 25 November 2011 15:35, Max Filippov <jcmvb...@gmail.com> wrote: >> Breakpoint 7, cpu_arm_exec (env=0x102033200) at ~/qemu-0.15.0/cpu-exec.c:557 >> 557 next_tb = tcg_qemu_tb_exec(env, tc_ptr); >> (gdb) p/x env->regs >> $13 = {0x4002c00c, 0x20, 0x4, 0x0, 0x0, 0x0, 0x40000, 0x0, 0x0, 0x0, 0x0, >> 0x0, 0x30, 0x10007fa8, 0x560d, 0x560c} >> (gdb) s >> 558 if ((next_tb & 3) == 2) { >> (gdb) p/x env->regs >> $14 = {0x10048000, 0x20, 0x4, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, >> 0x30, 0x10007fb8, 0x560d, 0x0} >> >> How to check access to unallocated memory? It's not seg faulting. > > 290 0000042c <_init>: > 291 42c: b5f8 push {r3, r4, r5, r6, r7, lr} > > set breakpoint here and see with x/6wx $sp whether saved register values are > good. To clarify this a bit: that means "set a breakpoint in an ARM gdb attached to qemu's gdb-stub interface". That gdb will see the view of the guest CPU, whereas connecting an x86 gdb directly to qemu you're looking at qemu's internal data structures, which can be more confusing. -- PMM