"Running X twice" problem: system hangup

[NAKAJI Hiroyuki]

Subject is changed. Thank you for the comment.

I write again about my X problem on pc98.

FreeBSD/pc98 7.0-CURRENT
PC-9821Ra333 (Celeron 333MHz)
VGA is Millenium MGA-2064W (sorry, not Millenium II)

$ pciconf -lv
hostb0 at pci0:0:0:        class=0x060000 card=0x00000000 chip=0x12378086 rev=0x02 hdr=0x00
    vendor   = 'Intel Corporation'
    device   = '82440/1FX 440FX (Natoma) System Controller'
    class    = bridge
    subclass = HOST-PCI
isab0 at pci0:6:0: class=0x068000 card=0x00000000 chip=0x002c1033 rev=0x01 hdr=0x00
    vendor   = 'NEC Electronics Hong Kong'
    class    = bridge
vgapci0 at pci0:7:0:       class=0x038000 card=0x00000000 chip=0x00091033 rev=0x03 hdr=0x00
    vendor   = 'NEC Electronics Hong Kong'
    device   = 'GUI Accelerator for 98'
    class    = display
vgapci1 at pci0:8:0:       class=0x030000 card=0x00000000 chip=0x96601023 rev=0xd3 hdr=0x00
    vendor   = 'Trident Microsystems'
    device   = 'TGUI9660XGi/968x/938x GUI Accelerator'
    class    = display
    subclass = VGA
fxp0 at pci0:11:0: class=0x020000 card=0x80001033 chip=0x12298086 rev=0x02 hdr=0x00
    vendor   = 'Intel Corporation'
    device   = '82550/1/7/8/9 EtherExpress PRO/100(B) Ethernet Adapter'
    class    = network
    subclass = ethernet
sym0 at pci0:12:0: class=0x010000 card=0x00000000 chip=0x000f1000 rev=0x03 hdr=0x00
    vendor   = 'LSI Logic (Was: Symbios Logic, NCR)'
    device   = 'LSI53C875/E,LSI53C876/E PCI to Ultra SCSI I/O Processor'
    class    = mass storage
    subclass = SCSI
vgapci2 at pci0:13:0:      class=0x038000 card=0x00000000 chip=0x0519102b rev=0x01 hdr=0x00
    vendor   = 'Matrox Electronic Systems Ltd.'
    device   = 'MGA-2064W Storm (Millennium board)'
    class    = display

And the problem occurs in following sequence.

> > o Boot FreeBSD/pc98
> > o login
> > o run 'startx'
> > o quit Xorg server
> > o run 'startx' again
> > o kernel panic and hangup
> > o no operation ...

Here, with yesterday's kernel and Xorg 6.9 server, no panic but only
hangup.

> If it's a kernel panic, then it's almost surely a FreeBSD issue, and
> you'd need to get a backtrace somehow and submit a PR.  Serial console
> is the usual method to get a backtrace if you can't get a dump while in
> X.

I set up my serial console and found that "running X twice" just hang
up the system. No kernel panic nor core dump of X does occur. What I
can only do here, is to press power button twice.
-- 
NAKAJI Hiroyuki