It is a bit weird that www.qemu.org tells me to report my bugs on launchpad, but replies to my bug report then appear ONLY on the developer mailing list. How shall a lowly end-user know that he must look there, too?
Anyway. On the developer mailing list, Markus Armbruster (Mon, 21 Feb 2011 09:00:25 +0100) requested: > Stack backtrace, please! When recompiling qemu 0.14.0 with "--enable-debug" for that purpose I also played a bit with the CFLAGS. It turns out that qemu segfaults when compiled with "-Os" in the CFLAGS, but not when compiled without "-O<whatever>" in the CFLAGS. The GCC version is 4.5.2. I have now probably lost the audience. But nevermind, here is the stack backtrace from qemu compiled with "-Os": root [~/sandbox] gdb qemu GNU gdb (GDB) 7.2 Copyright (C) 2010 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "i686-pc-linux-gnu". For bug reporting instructions, please see: <http://www.gnu.org/software/gdb/bugs/>... Reading symbols from /usr/bin/qemu...done. (gdb) r Starting program: /usr/bin/qemu [Thread debugging using libthread_db enabled] Program received signal SIGSEGV, Segmentation fault. raise_interrupt (intno=13, is_int=0, error_code=8, next_eip_addend=0) at /root/sandbox/stage4/qemu-0.14.0/target-i386/op_helper.c:1340 1340 env->exception_index = intno; (gdb) bt #0 raise_interrupt (intno=13, is_int=0, error_code=8, next_eip_addend=0) at /root/sandbox/stage4/qemu-0.14.0/target-i386/op_helper.c:1340 #1 0x08146e13 in raise_exception_err (exception_index=13, error_code=8) at /root/sandbox/stage4/qemu-0.14.0/target-i386/op_helper.c:1351 #2 0xda9abe00 in ?? () #3 0x00000000 in ?? () (gdb) and for comparison, the stack backtrace after compiling qemu with no CFLAGS at all: root [~/sandbox] gdb qemu GNU gdb (GDB) 7.2 Copyright (C) 2010 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "i686-pc-linux-gnu". For bug reporting instructions, please see: <http://www.gnu.org/software/gdb/bugs/>... Reading symbols from /usr/bin/qemu...done. (gdb) r Starting program: /usr/bin/qemu [Thread debugging using libthread_db enabled] Program exited normally. (gdb) bt No stack. (gdb) -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/722311 Title: Segmentation fault if started without -enable-kvm parameter Status in QEMU: New Bug description: I start qemu (Linux) from the same USB memory stick on several computers. Up to and including qemu 0.12.5, I could use or not use qemu's "-enable-kvm" command line parameter as appropriate for the hardware, and qemu would run. In contrast, qemu 0.13.0 and 0.14.0 segfault if started without "-enable-kvm". I get a black window appearing for fractions of a second, disappearing immediately, and then the error message "Segmentation fault". Hardware: Pentium 4, and Core 2 Duo. Command line: either "qemu" or "qemu -enable-kvm" (after manually loading the kvm-intel module on the Core 2 Duo). Reproducible: always.
