On Tue, Aug 5, 2025 at 7:00 PM Daniel P. Berrangé <berra...@redhat.com> wrote: > > On Tue, Aug 05, 2025 at 12:19:26PM +0300, Manos Pitsidianakis wrote: > > Add a backtrace_on_error meson feature (enabled with > > --enable-backtrace-on-error) that compiles system binaries with > > -rdynamic option and prints a function backtrace on error to stderr. > > > > Example output by adding an unconditional error_setg on error_abort in > > hw/arm/boot.c: > > > > ./qemu-system-aarch64(+0x13b4a2c) [0x55d015406a2c] > > ./qemu-system-aarch64(+0x13b4abd) [0x55d015406abd] > > ./qemu-system-aarch64(+0x13b4d49) [0x55d015406d49] > > ./qemu-system-aarch64(error_setg_internal+0xe7) [0x55d015406f62] > > ./qemu-system-aarch64(arm_load_dtb+0xbf) [0x55d014d7686f] > > ./qemu-system-aarch64(+0xd2f1d8) [0x55d014d811d8] > > ./qemu-system-aarch64(notifier_list_notify+0x44) [0x55d01540a282] > > ./qemu-system-aarch64(qdev_machine_creation_done+0xa0) [0x55d01476ae17] > > ./qemu-system-aarch64(+0xaa691e) [0x55d014af891e] > > ./qemu-system-aarch64(qmp_x_exit_preconfig+0x72) [0x55d014af8a5d] > > ./qemu-system-aarch64(qemu_init+0x2a89) [0x55d014afb657] > > ./qemu-system-aarch64(main+0x2f) [0x55d01521e836] > > /lib/x86_64-linux-gnu/libc.so.6(+0x29ca8) [0x7f3033d67ca8] > > /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x85) [0x7f3033d67d65] > > ./qemu-system-aarch64(_start+0x21) [0x55d0146814f1] > > > > Unexpected error in arm_load_dtb() at ../hw/arm/boot.c:529: > > From an end-user POV, IMHO the error messages need to be good enough > that such backtraces aren't needed to understand the problem. For > developers, GDB can give much better backtraces (file+line numbers, > plus parameters plus local variables) in the ideally rare cases that > the error message alone has insufficient info. So I'm not really > convinced that programs (in general, not just QEMU) should try to > create backtraces themselves.
Hi Daniel, I don't think there's value in replacing gdb debugging with this, I agree. I think it has value for "fire and forget" uses, when errors happen unexpectedly and are hard to replicate and you only end up with log entries and no easy way to debug it. -- Manos Pitsidianakis Emulation and Virtualization Engineer at Linaro Ltd
