<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - Uninitialized variables leads to random segfaults (valgrind log, apitrace attached)" href="https://bugs.freedesktop.org/show_bug.cgi?id=94955#c1">Comment # 1</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - Uninitialized variables leads to random segfaults (valgrind log, apitrace attached)" href="https://bugs.freedesktop.org/show_bug.cgi?id=94955">bug 94955</a> from <a class="email" href="mailto:brianp@vmware.com" title="Brian Paul <brianp@vmware.com>"> Brian Paul</a> <pre>(In reply to David Lonie from <a href="show_bug.cgi?id=94955#c0">comment #0</a>) > Created <a href="attachment.cgi?id=122975" name="attach_122975" title="apitrace">attachment 122975</a> <a href="attachment.cgi?id=122975&action=edit" title="apitrace">[details]</a> > apitrace > > There are some uninitialized variables in current master that are causing > some of the VTK unit tests to segfault randomly, or just not produce any > output. I've included as much information as I can think of below. > > Feel free to ping me if more info is needed. > > -------------------------------------------- > Configure options: > > ./autogen.sh \ > --enable-debug \ > --prefix="$prefix" \ > --disable-dri \ > --disable-egl \ > --disable-gles1 \ > --disable-gles2 \ > --disable-shared-glapi \ > --enable-xlib-glx \ > --enable-gallium-osmesa \ > --with-gallium-drivers=swrast \ > --enable-gallium-llvm=yes \ > LLVM_CONFIG=/usr/bin/llvm-config-3.6 \ > --enable-llvm-shared-libs \ > --with-gl-lib-name=MesaGL \ > --with-osmesa-lib-name=MesaOSMesa > > --------------------------------------------- > Install with: > > make install-data > cd src/gallium > make install-exec > > (Regular 'make install' does this in the install dir for some reason: > > $ ls mesa-master-install/lib/libMesaGL.so* -lh > > mesa-master-install/lib/libMesaGL.so -> libMesaGL.so.1.5.0 > > mesa-master-install/lib/libMesaGL.so.1 -> libMesaGL.so.1.6.0 > mesa-master-install/lib/libMesaGL.so.1.5.0 > mesa-master-install/lib/libMesaGL.so.1.6.0 > > which confuses my linker/loader ;) Another bug?) > > --------------------------------------------- > memcheck the attached apitrace with (obviously change paths as needed): > > MESA_GL_VERSION_OVERRIDE=4.5 \ > LD_LIBRARY_PATH=/ssd/src/llvm-3.8.0.install/lib \ > LD_PRELOAD=/ssd/src/mesa-master-install/lib/libMesaGL.so \ > valgrind --tool=memcheck \ > glretrace vtkRenderingOpenGL2CxxTests.4075.trim.trace > > --------------------------------------------- > Sample valgrind stacks: > ==32054== Conditional jump or move depends on uninitialised value(s) > ==32054== at 0x5367CF7: util_framebuffer_state_equal (u_framebuffer.c:58) > ==32054== by 0x5444AFE: llvmpipe_set_framebuffer_state > (lp_state_surface.c:54) > ==32054== by 0x53561DA: util_blitter_blit_generic (u_blitter.c:1694) > ==32054== by 0x5356819: util_blitter_blit (u_blitter.c:1813) > ==32054== by 0x544602C: lp_blit (lp_surface.c:117) > ==32054== by 0x51705F7: st_CopyTexSubImage (st_cb_texture.c:2672) > ==32054== by 0x50B2B03: copytexsubimage_by_slice (teximage.c:3459) > ==32054== by 0x50B330D: copyteximage (teximage.c:3644) > ==32054== by 0x50B3476: _mesa_CopyTexImage2D (teximage.c:3680) > ==32054== by 0x4D340E: ??? (in /usr/bin/glretrace) > ==32054== by 0x40CCCC: ??? (in /usr/bin/glretrace) > ==32054== by 0x40D2A7: ??? (in /usr/bin/glretrace) This one looks easy to fix. Though, I wasn't able to reproduce the valgrind warning here with piglit's copytexsubimage test which definitely hits the same code path. > ==32054== Conditional jump or move depends on uninitialised value(s) > ==32054== at 0x5409DEE: lp_build_blend_factor_unswizzled > (lp_bld_blend_aos.c:98) > ==32054== by 0x540A2A5: lp_build_blend_factor (lp_bld_blend_aos.c:262) > ==32054== by 0x540A53C: lp_build_blend_aos (lp_bld_blend_aos.c:352) > ==32054== by 0x543C200: generate_unswizzled_blend (lp_state_fs.c:2094) > ==32054== by 0x543D32D: generate_fragment (lp_state_fs.c:2434) > ==32054== by 0x543DEAC: generate_variant (lp_state_fs.c:2619) > ==32054== by 0x543F464: llvmpipe_update_fs (lp_state_fs.c:3171) > ==32054== by 0x5435D35: llvmpipe_update_derived (lp_state_derived.c:209) > ==32054== by 0x5410AC0: llvmpipe_draw_vbo (lp_draw_arrays.c:70) > ==32054== by 0x52E28C4: cso_draw_vbo (cso_context.c:1629) > ==32054== by 0x5174712: st_draw_vbo (st_draw.c:251) > ==32054== by 0x511BE24: vbo_validated_drawrangeelements > (vbo_exec_array.c:844) I don't see what's wrong here. At lp_bld_blend_aos.c:98 we're examining fields of the bld object. But the whole bld object is initialized to zeros at line 321. > > ==32054== Conditional jump or move depends on uninitialised value(s) > ==32054== at 0x404002D: ??? > ==32054== by 0x5415736: lp_rast_shade_quads_mask (lp_rast.c:457) > ==32054== by 0x541999F: lp_rast_triangle_32_3_16 (lp_rast_tri.c:346) > ==32054== by 0x5415A81: do_rasterize_bin (lp_rast.c:609) > ==32054== by 0x5415AEF: rasterize_bin (lp_rast.c:628) > ==32054== by 0x5415BFE: rasterize_scene (lp_rast.c:688) > ==32054== by 0x5415EE3: thread_function (lp_rast.c:828) > ==32054== by 0x5413C4A: impl_thrd_routine (threads_posix.h:87) > ==32054== by 0x5BF6423: start_thread (in /usr/lib/libpthread-2.23.so) > ==32054== by 0x720CCBC: clone (in /usr/lib/libc-2.23.so) Not sure about this one. I suspect our jitted code does some vector ops on some unused elements and that triggers the valgrind warning, but that should be harmless. Roland??</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are the assignee for the bug.</li> </ul> </body> </html>