Max, Qemu still crashes for me, but the debug is again very different. When I attach to the qemu process from gdb, it is unable to provide a backtrace when it crashes. The log file is different too. Any ideas? qemu-system-x86_64: block.c:2307: bdrv_replace_in_backing_chain: Assertion `!bdrv_requests_pending(old)' failed. (gdb) attach 5563 Attaching to process 5563 Reading symbols from /usr/bin/qemu-system-x86_64...cdone. oReading symbols from /usr/lib64/libepoxy.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libdrm.so.2...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgbm.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libX11.so.6...n(no debugging symbols found)...done. Reading symbols from /usr/lib64/libz.so.1...(no debugging symbols found)...done. Reading symbols from /lib64/libaio.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libiscsi.so.4...done. Reading symbols from /usr/lib64/libcurl.so.4...(no debugging symbols found)...done. Reading symbols from /lib64/libacl.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgfapi.so.0...done. Reading symbols from /usr/lib64/libglusterfs.so.0...done. Reading symbols from /usr/lib64/libgfrpc.so.0...done. Reading symbols from /usr/lib64/libgfxdr.so.0...done. Reading symbols from /lib64/libuuid.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libssh2.so.1...done. Reading symbols from /lib64/libbz2.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libpixman-1.so.0...(no debugging symbols found)...done. Reading symbols from /lib64/libutil.so.1...(no debugging symbols found)...done. Reading symbols from /lib64/libncurses.so.5...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libpng16.so.16...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libjpeg.so.62...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libsasl2.so.3...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libSDL-1.2.so.0...(no debugging symbols found)...done. Reading symbols from /lib64/libpthread.so.0...(no debugging symbols found)...done. [New LWP 5588] [New LWP 5587] [New LWP 5586] [New LWP 5585] [New LWP 5584] [New LWP 5583] [New LWP 5582] [New LWP 5581] [New LWP 5580] [New LWP 5579] [New LWP 5578] [New LWP 5577] [New LWP 5576] [New LWP 5575] [New LWP 5574] [New LWP 5573] [New LWP 5572] [New LWP 5571] [New LWP 5570] [New LWP 5568] [New LWP 5567] [New LWP 5566] [New LWP 5564] [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib64/libthread_db.so.1". Reading symbols from /usr/lib64/libvte.so.9...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgtk-x11-2.0.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgdk-x11-2.0.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libpangocairo-1.0.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libatk-1.0.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgdk_pixbuf-2.0.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libpangoft2-1.0.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libpango-1.0.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libfontconfig.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libfreetype.so.6...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgio-2.0.so.0...t(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgobject-2.0.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libglib-2.0.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libcairo.so.2...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libXext.so.6...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libnettle.so.6...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgnutls.so.30...(no debugging symbols found)...done. Reading symbols from /usr/lib64/liblzo2.so.2...done. Reading symbols from /usr/lib64/libspice-server.so.1...done. Reading symbols from /usr/lib64/libcacard.so.0...done. Reading symbols from /usr/lib64/libusb-1.0.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgthread-2.0.so.0...(no debugging symbols found)...done. Reading symbols from /lib64/librt.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libstdc++.so.6...(no debugging symbols found)...done. Reading symbols from /lib64/libm.so.6...i(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgcc_s.so.1...(no debugging symbols found)...done. Reading symbols from /lib64/libc.so.6...(no debugging symbols found)...done. Reading symbols from /lib64/ld-linux-x86-64.so.2...(no debugging symbols found)...done. Reading symbols from /lib64/libdl.so.2...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libexpat.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libxcb.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libXau.so.6...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libXdmcp.so.6...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgcrypt.so.20...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgpg-error.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libidn.so.11...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libssl.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libcrypto.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/liblber-2.4.so.2...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libldap-2.4.so.2...(no debugging symbols found)...done. Reading symbols from /lib64/libattr.so.1...(no debugging symbols found)...done. Reading symbols from /lib64/libresolv.so.2...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libXrandr.so.2...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libXrender.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libvga.so.1...done. Reading symbols from /usr/lib64/../lib64/libgmodule-2.0.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libffi.so.6...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libharfbuzz.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libEGL.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libxcb-shm.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libGL.so.1...n(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libglapi.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libXdamage.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libXfixes.so.3...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libX11-xcb.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libxcb-glx.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libxcb-dri2.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libxcb-dri3.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libxcb-present.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libxcb-randr.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libxcb-xfixes.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libxcb-render.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libxcb-shape.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libxcb-sync.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libxshmfence.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libXxf86vm.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libXinerama.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libXi.so.6...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libXcursor.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/../lib64/libXcomposite.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libp11-kit.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libhogweed.so.4...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgmp.so.10...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libnss3.so...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libsmime3.so...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libssl3.so...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libsoftokn3.so...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libnssutil3.so...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libplds4.so...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libplc4.so...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libnspr4.so...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libsqlite3.so.0...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libicui18n.so.56...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libicuuc.so.56...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libicudata.so.56...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libcelt051.so.0...done. Reading symbols from /usr/lib64/liblz4.so.1...(no debugging symbols found)...done. Reading symbols from /lib64/libudev.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/sasl2/libsasldb.so.3...(no debugging symbols found)...done. Reading symbols from /usr/lib64/libgdbm.so.4...(no debugging symbols found)...done. Reading symbols from /usr/lib64/sasl2/libotp.so.3...(no debugging symbols found)...done. Reading symbols from /usr/lib64/sasl2/libdigestmd5.so.3...(no debugging symbols found)...done. Reading symbols from /usr/lib64/sasl2/libcrammd5.so.3...(no debugging symbols found)...done. Reading symbols from /usr/lib64/sasl2/liblogin.so.3...(no debugging symbols found)...done. Reading symbols from /lib64/libcrypt.so.1...(no debugging symbols found)...done. Reading symbols from /usr/lib64/sasl2/libplain.so.3...(no debugging symbols found)...done. Reading symbols from /usr/lib64/sasl2/libscram.so.3...(no debugging symbols found)...done. 0x00007f12852f83d1 in ppoll () from /lib64/libc.so.6 (gdb) continue Continuing. [Thread 0x7f115b7fe700 (LWP 5576) exited] [Thread 0x7f127aa76700 (LWP 5566) exited] [Thread 0x7f1159ffb700 (LWP 5579) exited] [Thread 0x7f115affd700 (LWP 5577) exited] [Thread 0x7f116a0e2700 (LWP 5571) exited] [Thread 0x7f1158ff9700 (LWP 5581) exited] [Thread 0x7f11690e0700 (LWP 5573) exited] [Thread 0x7f11597fa700 (LWP 5580) exited] [Thread 0x7f115bfff700 (LWP 5575) exited] [Thread 0x7f11688df700 (LWP 5574) exited] [Thread 0x7f115a7fc700 (LWP 5578) exited] [Thread 0x7f11698e1700 (LWP 5572) exited] [New Thread 0x7f11698e1700 (LWP 5631)] [New Thread 0x7f115a7fc700 (LWP 5632)] [New Thread 0x7f11688df700 (LWP 5633)] [New Thread 0x7f115bfff700 (LWP 5634)] [New Thread 0x7f127aa76700 (LWP 5635)] [New Thread 0x7f116a0e2700 (LWP 5636)] [New Thread 0x7f11690e0700 (LWP 5637)] [New Thread 0x7f115b7fe700 (LWP 5638)] [New Thread 0x7f115affd700 (LWP 5639)] [New Thread 0x7f1159ffb700 (LWP 5640)] [New Thread 0x7f11597fa700 (LWP 5641)] [New Thread 0x7f1158ff9700 (LWP 5642)] [New Thread 0x7f1117fff700 (LWP 5643)] [New Thread 0x7f11177fe700 (LWP 5644)] [New Thread 0x7f1116ffd700 (LWP 5645)] [New Thread 0x7f11167fc700 (LWP 5646)] [New Thread 0x7f1115ffb700 (LWP 5647)] [New Thread 0x7f11157fa700 (LWP 5648)] [New Thread 0x7f1114ff9700 (LWP 5649)] [New Thread 0x7f11147f8700 (LWP 5650)] [New Thread 0x7f1113ff7700 (LWP 5651)] [New Thread 0x7f11137f6700 (LWP 5652)] [New Thread 0x7f1112ff5700 (LWP 5653)] Thread 1 "qemu-system-x86" received signal SIGABRT, Aborted. 0x00007f12852323f8 in raise () from /lib64/libc.so.6 (gdb) Continuing. Couldn't get registers: No such process. Couldn't get registers: No such process. Couldn't get registers: No such process. (gdb) Continuing. Couldn't get registers: No such process. (gdb) [Thread 0x7f1112ff5700 (LWP 5653) exited] [Thread 0x7f11137f6700 (LWP 5652) exited] [Thread 0x7f1113ff7700 (LWP 5651) exited] [Thread 0x7f11147f8700 (LWP 5650) exited] [Thread 0x7f1114ff9700 (LWP 5649) exited] [Thread 0x7f11157fa700 (LWP 5648) exited] [Thread 0x7f1115ffb700 (LWP 5647) exited] [Thread 0x7f1116ffd700 (LWP 5645) exited] [Thread 0x7f11177fe700 (LWP 5644) exited] [Thread 0x7f1117fff700 (LWP 5643) exited] [Thread 0x7f1158ff9700 (LWP 5642) exited] [Thread 0x7f11597fa700 (LWP 5641) exited] [Thread 0x7f1159ffb700 (LWP 5640) exited] [Thread 0x7f115affd700 (LWP 5639) exited] [Thread 0x7f115b7fe700 (LWP 5638) exited] [Thread 0x7f11690e0700 (LWP 5637) exited] [Thread 0x7f116a0e2700 (LWP 5636) exited] [Thread 0x7f127aa76700 (LWP 5635) exited] [Thread 0x7f115bfff700 (LWP 5634) exited] [Thread 0x7f11688df700 (LWP 5633) exited] [Thread 0x7f115a7fc700 (LWP 5632) exited] [Thread 0x7f11698e1700 (LWP 5631) exited] [Thread 0x7f1134ff9700 (LWP 5588) exited] [Thread 0x7f11357fa700 (LWP 5587) exited] [Thread 0x7f1135ffb700 (LWP 5586) exited] [Thread 0x7f11367fc700 (LWP 5585) exited] [Thread 0x7f1136ffd700 (LWP 5584) exited] [Thread 0x7f11377fe700 (LWP 5583) exited] [Thread 0x7f1137fff700 (LWP 5582) exited] [Thread 0x7f1272dff700 (LWP 5570) exited] [Thread 0x7f1278961700 (LWP 5568) exited] [Thread 0x7f1279162700 (LWP 5567) exited] [Thread 0x7f127b277700 (LWP 5564) exited] [Thread 0x7f128d35cb00 (LWP 5563) exited] Continuing. Cannot execute this command without a live selected thread. (gdb) Continuing. Cannot execute this command without a live selected thread. (gdb) Continuing. Cannot execute this command without a live selected thread. (gdb)