Frederik Thuysbaert
2013-Aug-16 08:27 UTC
Re: Xen blktap driver for Ceph RBD : Anybody wants to test ? :p
Hi Sylvain,>> I''m not quite sure what u mean, can u give some more information on how I do >> this? I compiled tapdisk with ./configure CFLAGS=-g, but I''m not sure this >> is what u meant. > > Yes, ./configure CFLAGS=-g LDFLAGS=-g is a good start. > >... > > Then once you have a core file, you can use gdb along with the tapdisk > executable to generate a meaningful backtrace of where the crash >I did 2 runs, with a cold reboot in between just to be sure. I don''t think I''m getting a lot of valuable information, but I will post it anyway. The reason for the cold reboot was a ''Cannot access memory at address ...'' in gdb after the first frame, I thought it could help. Here''s what I got: try 1: Core was generated by `tapdisk''. Program terminated with signal 11, Segmentation fault. #0 0x00007fb42d2082d7 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0 (gdb) bt #0 0x00007fb42d2082d7 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0 Cannot access memory at address 0x7fb42f081c38 (gdb) frame 0 #0 0x00007fb42d2082d7 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/x86_64-linux-gnu/libpthread.so.0 (gdb) list 77 } 78 79 int 80 main(int argc, char *argv[]) 81 { 82 char *control; 83 int c, err, nodaemon; 84 FILE *out; 85 86 control = NULL; (gdb) info locals No symbol table info available. try 2: Core was generated by `tapdisk''. Program terminated with signal 11, Segmentation fault. #0 0x00007fe05a721e6b in poll () from /lib/x86_64-linux-gnu/libc.so.6 (gdb) bt #0 0x00007fe05a721e6b in poll () from /lib/x86_64-linux-gnu/libc.so.6 Cannot access memory at address 0x7fe05c2ba518 (gdb) frame 0 #0 0x00007fe05a721e6b in poll () from /lib/x86_64-linux-gnu/libc.so.6 (gdb) list 77 } 78 79 int 80 main(int argc, char *argv[]) 81 { 82 char *control; 83 int c, err, nodaemon; 84 FILE *out; 85 86 control = NULL; (gdb) info locals No symbol table info available. Regards, - Frederik