4.3.2. KDB ARM
TODO neither arm and aarch64 are working as of 1cd1e58b023791606498ca509256cc48e95e4f5b + 1.
arm seems to place and hit the breakpoint correctly, but no matter how many go commands I do, the count.sh stdout simply does not show.
aarch64 seems to place the breakpoint correctly, but after the first go the kernel oopses with warning:
WARNING: CPU: 0 PID: 46 at /root/linux-kernel-module-cheat/submodules/linux/kernel/smp.c:416 smp_call_function_many+0xdc/0x358
and stack trace:
smp_call_function_many+0xdc/0x358 kick_all_cpus_sync+0x30/0x38 kgdb_flush_swbreak_addr+0x3c/0x48 dbg_deactivate_sw_breakpoints+0x7c/0xb8 kgdb_cpu_enter+0x284/0x6a8 kgdb_handle_exception+0x138/0x240 kgdb_brk_fn+0x2c/0x40 brk_handler+0x7c/0xc8 do_debug_exception+0xa4/0x1c0 el1_dbg+0x18/0x78 __arm64_sys_write+0x0/0x30 el0_svc_handler+0x74/0x90 el0_svc+0x8/0xc
My theory is that every serious ARM developer has JTAG, and no one ever tests this, and the kernel code is just broken.