Re: xsrc/50093: 7.0_RC1 Xorg server gets SIGSEGV on exit

[Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>]

The following reply was made to PR xsrc/50093; it has been noted by GNATS.

From: Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>
To: mrg%eterna.com.au@localhost
Cc: gnats-bugs%NetBSD.org@localhost, tsutsui%ceres.dti.ne.jp@localhost
Subject: Re: xsrc/50093: 7.0_RC1 Xorg server gets SIGSEGV on exit
Date: Wed, 29 Jul 2015 22:52:07 +0900

 mrg@ wrote:
 
 > this seems like a duplicate of PR#49553 we haven't figured out
 > what is happening yet.
 
 I wonder if it's the same thing because the PR is spin, not SIGSEGV.
 
 On Intel 855GM machine (with patch as mentioned in PR/49875)
 Xorg also gets SIGSEGV on exit:
 
 ---
  :
 
 (==) Log file: "/var/log/Xorg.0.log", Time: Wed Jul 29 22:40:23 2015
 (==) Using default built-in configuration (21 lines)
 The XKEYBOARD keymap compiler (xkbcomp) reports:
 > Error:            Couldn't lookup keysym
 >                   Symbol interpretation ignored
 > Error:            Couldn't lookup keysym
 >                   Symbol interpretation ignored
 Errors from xkbcomp are not fatal to the X server
 Segmentation fault at address 0xbaefce29
 
 Fatal server error:
 Caught signal 11 (Segmentation fault). Server aborting
 
  :
 ---
 
 According to pmap(1), the address 0xbaefce29 is in mesa_dri_drivers.so:
 ---
 08048000   2188K read/exec         /usr/X11R7/bin/Xorg
 0826B000     40K read/write        /usr/X11R7/bin/Xorg
 08275000    556K read/write          [ anon ]
 BA300000     64K read/write          [ anon ]
 BA310000    960K read/write          [ anon ]
 BA400000     64K read/write          [ anon ]
 BA410000    960K read/write          [ anon ]
 BA500000     64K read/write          [ anon ]
 BA510000    960K read/write          [ anon ]
 BA600000   3072K read/write          [ ?? 0xc0b61ae0 ?? ]
 BA900000     64K read/write          [ anon ]
 BA910000    960K read/write          [ anon ]
 BAA6A000    912K read/exec         /usr/lib/libstdc++.so.7.3
 BAB4E000     20K read/write        /usr/lib/libstdc++.so.7.3
 BAB53000     28K read/write          [ anon ]
 BAB5A000     48K read/exec         /usr/X11R7/lib/libdrm_radeon.so.0.0
 BAB66000      4K read/write        /usr/X11R7/lib/libdrm_radeon.so.0.0
 BAB67000    216K read/exec         /usr/X11R7/lib/libglapi.so.0.0
 BAB9D000     12K read/write        /usr/X11R7/lib/libglapi.so.0.0
 BABA0000      4K read/write          [ anon ]
 BABA1000    144K read/exec         /usr/lib/libexpat.so.2.1
 BABC5000      8K read/write        /usr/lib/libexpat.so.2.1
 BABC7000   5080K read/exec         /usr/X11R7/lib/modules/dri/mesa_dri_drivers.so.0
 BB0BD000     88K read/write        /usr/X11R7/lib/modules/dri/mesa_dri_drivers.so.0
 BB0D3000    224K read/write          [ anon ]
 BB10B000    256K read/write          [ uvm_aobj ]
 BB14B000     16K read/exec         /usr/X11R7/lib/modules/drivers/kbd_drv.so.1
 BB14F000      8K read/write        /usr/X11R7/lib/modules/drivers/kbd_drv.so.1
 BB151000     40K read/exec         /usr/X11R7/lib/modules/drivers/mouse_drv.so.1
 BB15B000      4K read/write        /usr/X11R7/lib/modules/drivers/mouse_drv.so.1
 BB161000      4K read/write          [ uvm_aobj ]
 BB162000      4K read/write          [ uvm_aobj ]
 BB163000    132K read/exec         /usr/X11R7/lib/libdrm_intel.so.0.0
 BB184000      4K read/write        /usr/X11R7/lib/libdrm_intel.so.0.0
 BB185000   1468K read/exec         /usr/X11R7/lib/modules/drivers/intel_drv.so.2
 BB2F4000     24K read/write        /usr/X11R7/lib/modules/drivers/intel_drv.so.2
 BB2FA000     20K read/exec         /usr/X11R7/lib/modules/extensions/libdri2.so.0
 BB2FF000      4K read/write        /usr/X11R7/lib/modules/extensions/libdri2.so.0
 
 ---
 
 But mesa_dri_drivers.so seems unloaded when the Xorg
 (attached by gdb from other pty) gets SIGSEGV:
 ---
 08048000   1312K read/exec         /usr/X11R7/bin/Xorg
 08190000     64K read/exec         /usr/X11R7/bin/Xorg
 081A0000    812K read/exec         /usr/X11R7/bin/Xorg
 0826B000     40K read/write        /usr/X11R7/bin/Xorg
 08275000    556K read/write          [ anon ]
 BA300000     64K read/write          [ anon ]
 BA310000    960K read/write          [ anon ]
 BA400000     64K read/write          [ anon ]
 BA410000    960K read/write          [ anon ]
 BA500000     64K read/write          [ anon ]
 BA510000    960K read/write          [ anon ]
 BA600000   3072K read/write          [ ?? 0xc0b61ae0 ?? ]
 BA900000     64K read/write          [ anon ]
 BA910000    960K read/write          [ anon ]
 BB10B000    256K read/write          [ uvm_aobj ]
 BB14B000     16K read/exec         /usr/X11R7/lib/modules/drivers/kbd_drv.so.1
 BB14F000      8K read/write        /usr/X11R7/lib/modules/drivers/kbd_drv.so.1
 BB151000     40K read/exec         /usr/X11R7/lib/modules/drivers/mouse_drv.so.1
 BB15B000      4K read/write        /usr/X11R7/lib/modules/drivers/mouse_drv.so.1
 BB161000      4K read/write          [ uvm_aobj ]
 BB163000    132K read/exec         /usr/X11R7/lib/libdrm_intel.so.0.0
 BB184000      4K read/write        /usr/X11R7/lib/libdrm_intel.so.0.0
 BB185000   1468K read/exec         /usr/X11R7/lib/modules/drivers/intel_drv.so.2
 BB2F4000     24K read/write        /usr/X11R7/lib/modules/drivers/intel_drv.so.2
 BB2FA000     20K read/exec         /usr/X11R7/lib/modules/extensions/libdri2.so.0
 BB2FF000      4K read/write        /usr/X11R7/lib/modules/extensions/libdri2.so.0
 ---
 so gdb can't get any symbol info even with debug builds.
 
 Note kbd_drv.so and mouse_drv.so are not unloaded
 while /var/log/Xorg.0.log says:
 ---
 [  2147.036] (II) UnloadModule: "mouse"
 [  2147.036] (II) Unloading mouse
 [  2147.054] (II) UnloadModule: "kbd"
 [  2147.054] (II) Unloading kbd
 ---
 
 In VESA driver (QEMU or VirtualBox), the SIGSEGV address seems
 in gallium_dri.so.0.
 
 ---
 Izumi Tsutsui