[gem5-dev] Re: Debugging application inside gem5 (m5term)
Hi Ciro, runn Thanks for the response. Yeah, even we couldn't make the gdbserver approach work. For the non-gdbserver approach you described, we tried it but we are still not able to hit the breakpoints on the app (by running gdb on the host system). I think I might have missed this earlier but using gdb inside m5term with the application is not an issue and works perfectly fine. It was that the libraries I was trying to step into didn't contain debug symbols on the guest OS, I thought connecting it with the host gdb and debugging the application on the host would be a better approach. (because on the host, I have seen that a few, if not all of the libraries, have been built with debug symbols) Thanks, Gaurav From: ciro.santi...@gmail.com Sent: Tuesday, May 19, 2020 3:24 PM To: gem5 Developer List Cc: Beckmann, Brad ; GAURAV JAIN Subject: Re: [gem5-dev] Debugging application inside gem5 (m5term) For the gdbserver approach, I haven't found a guest to host networking possibility in gem5 yet: https://stackoverflow.com/questions/48941494/how-to-do-port-forwarding-from-guest-to-host-and-vice-versa-in-gem5 but maybe I missed it. For a non-gdbserver approach, have you tried add-symbol-file as mentioned at https://stackoverflow.com/questions/26271901/is-it-possible-to-use-gdb-and-qemu-to-debug-linux-user-space-programs-and-kernel/46636070#46636070 and https://stackoverflow.com/questions/20380204/how-to-load-multiple-symbol-files-in-gdb BTW, have a look into lx-symbols to help with kernel modules in case you are not using it yet: https://cirosantilli.com/linux-kernel-module-cheat/#gdb-step-debug-kernel-module BTW2 Dealing with userland apps perfectly from gem5 GDB stub (including multiple userland programs with same address) asked at: https://stackoverflow.com/questions/9561546/thread-aware-gdb-for-the-linux-kernel On Tue, May 19, 2020 at 8:03 PM GAURAV JAIN via gem5-dev wrote: > > Hi All, > > We are trying to debug an application running inside gem5 full system. > > After running gem5, we are using 'gdb vmlinux' to attach to it so as to be > able to debug the kernel modules. > > One approach we tried was using the 'file' command to load the symbol table > for the application and continue. But then that approach would overwrite the > existing symbol table (for the kernel modules) with that of the application > which is not what we desire. > > The second approach we tried was running 'gdbserver' inside m5term and then > connect to it through a gdb instance running on the host. > > We did - 'gdbserver localhost:1234 ./app', which seemed to be successful in > launching a process and Listening on the port 1234. > > On the host, we did - 'gdb ./app' and from inside it, 'target remote :1234'. > Doing this did not work and we got the generic error - 'remote:1234 > connection timed out' > > It'd be great if someone could provide pointers on how can we debug an > application running in gem5 full system and if either of the two approaches > mentioned above would work. > > Thanks, > Gaurav > ___ > gem5-dev mailing list -- gem5-dev@gem5.org > To unsubscribe send an email to gem5-dev-le...@gem5.org > %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s ___ gem5-dev mailing list -- gem5-dev@gem5.org To unsubscribe send an email to gem5-dev-le...@gem5.org %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s
[gem5-dev] Re: Debugging application inside gem5 (m5term)
Hi Gaurav, As Ciro mentioned, I think what you need is add-symbol-file (to keep the existing symbol). To make my life easier, I would still rely on lx-symbols to load symbols for kernel modules as they are loaded, and only use add-symbol-file for the binary you want to debug along with the driver (possibly even after you are done loading kernel modules). Best, On Tue, May 19, 2020 at 1:25 PM Ciro Santilli via gem5-dev < gem5-dev@gem5.org> wrote: > For the gdbserver approach, I haven't found a guest to host networking > possibility in gem5 yet: > > https://stackoverflow.com/questions/48941494/how-to-do-port-forwarding-from-guest-to-host-and-vice-versa-in-gem5 > but maybe I missed it. > > For a non-gdbserver approach, have you tried add-symbol-file as > mentioned at > https://stackoverflow.com/questions/26271901/is-it-possible-to-use-gdb-and-qemu-to-debug-linux-user-space-programs-and-kernel/46636070#46636070 > and > https://stackoverflow.com/questions/20380204/how-to-load-multiple-symbol-files-in-gdb > > BTW, have a look into lx-symbols to help with kernel modules in case > you are not using it yet: > > https://cirosantilli.com/linux-kernel-module-cheat/#gdb-step-debug-kernel-module > > BTW2 Dealing with userland apps perfectly from gem5 GDB stub > (including multiple userland programs with same address) asked at: > > https://stackoverflow.com/questions/9561546/thread-aware-gdb-for-the-linux-kernel > > On Tue, May 19, 2020 at 8:03 PM GAURAV JAIN via gem5-dev > wrote: > > > > Hi All, > > > > We are trying to debug an application running inside gem5 full system. > > > > After running gem5, we are using 'gdb vmlinux' to attach to it so as to > be able to debug the kernel modules. > > > > One approach we tried was using the 'file' command to load the symbol > table for the application and continue. But then that approach would > overwrite the existing symbol table (for the kernel modules) with that of > the application which is not what we desire. > > > > The second approach we tried was running 'gdbserver' inside m5term and > then connect to it through a gdb instance running on the host. > > > > We did - 'gdbserver localhost:1234 ./app', which seemed to be successful > in launching a process and Listening on the port 1234. > > > > On the host, we did - 'gdb ./app' and from inside it, 'target remote > :1234'. > > Doing this did not work and we got the generic error - 'remote:1234 > connection timed out' > > > > It'd be great if someone could provide pointers on how can we debug an > application running in gem5 full system and if either of the two approaches > mentioned above would work. > > > > Thanks, > > Gaurav > > ___ > > gem5-dev mailing list -- gem5-dev@gem5.org > > To unsubscribe send an email to gem5-dev-le...@gem5.org > > %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s > ___ > gem5-dev mailing list -- gem5-dev@gem5.org > To unsubscribe send an email to gem5-dev-le...@gem5.org > %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s > -- Pouya Fotouhi PhD Candidate Department of Electrical and Computer Engineering University of California, Davis ___ gem5-dev mailing list -- gem5-dev@gem5.org To unsubscribe send an email to gem5-dev-le...@gem5.org %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s
[gem5-dev] Re: Debugging application inside gem5 (m5term)
For the gdbserver approach, I haven't found a guest to host networking possibility in gem5 yet: https://stackoverflow.com/questions/48941494/how-to-do-port-forwarding-from-guest-to-host-and-vice-versa-in-gem5 but maybe I missed it. For a non-gdbserver approach, have you tried add-symbol-file as mentioned at https://stackoverflow.com/questions/26271901/is-it-possible-to-use-gdb-and-qemu-to-debug-linux-user-space-programs-and-kernel/46636070#46636070 and https://stackoverflow.com/questions/20380204/how-to-load-multiple-symbol-files-in-gdb BTW, have a look into lx-symbols to help with kernel modules in case you are not using it yet: https://cirosantilli.com/linux-kernel-module-cheat/#gdb-step-debug-kernel-module BTW2 Dealing with userland apps perfectly from gem5 GDB stub (including multiple userland programs with same address) asked at: https://stackoverflow.com/questions/9561546/thread-aware-gdb-for-the-linux-kernel On Tue, May 19, 2020 at 8:03 PM GAURAV JAIN via gem5-dev wrote: > > Hi All, > > We are trying to debug an application running inside gem5 full system. > > After running gem5, we are using 'gdb vmlinux' to attach to it so as to be > able to debug the kernel modules. > > One approach we tried was using the 'file' command to load the symbol table > for the application and continue. But then that approach would overwrite the > existing symbol table (for the kernel modules) with that of the application > which is not what we desire. > > The second approach we tried was running 'gdbserver' inside m5term and then > connect to it through a gdb instance running on the host. > > We did - 'gdbserver localhost:1234 ./app', which seemed to be successful in > launching a process and Listening on the port 1234. > > On the host, we did - 'gdb ./app' and from inside it, 'target remote :1234'. > Doing this did not work and we got the generic error - 'remote:1234 > connection timed out' > > It'd be great if someone could provide pointers on how can we debug an > application running in gem5 full system and if either of the two approaches > mentioned above would work. > > Thanks, > Gaurav > ___ > gem5-dev mailing list -- gem5-dev@gem5.org > To unsubscribe send an email to gem5-dev-le...@gem5.org > %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s ___ gem5-dev mailing list -- gem5-dev@gem5.org To unsubscribe send an email to gem5-dev-le...@gem5.org %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s
