[Qemu-devel] WfW setup and DOS display.sys hanging

[Qemu-devel] WfW setup and DOS display.sys hanging

[Sebastian]

Hi,

I noticed in newer versions of Qemu (Debian Jessie) a regression causing 
DISPLAY.SYS from MS-DOS 6.22 to hang the system as soon as loaded.

The Windows for Workgroups 3.11 SETUP.EXE file hangs with a cleared 
screen and the cursor blinking in the top left of the screen. The 
DOSIDLE.EXE[1] file hangs after printing out some system information.

Git-Bisecting returned "roms: update vgabios binaries" (commit 
6eefccc0bb9c34051b1e21880fc3a1c1c8686edd) as the bad commit.

I tested the i386-softmmu target on Debian 7.3 (wheezy), x86_64 host and 
gcc 4.7.2 (Debian 4.7.2-5) without KVM support.

[1] Source and binary are available e.g. at 
http://maribu.home.xs4all.nl/zeurkous/download/mirror/dosidle/

Best Regards,
Sebastian

Re: [Qemu-devel] WfW setup and DOS display.sys hanging

[Kevin Wolf]

Hi Gerd,

Am 09.01.2014 um 00:20 hat Sebastian geschrieben:
> Hi,
> 
> I noticed in newer versions of Qemu (Debian Jessie) a regression
> causing DISPLAY.SYS from MS-DOS 6.22 to hang the system as soon as
> loaded.

now that you sent a pull request for a SeaBIOS update, I tried what
would happen with this one. Sadly, while it does fix my hanging Win 7
boot, DOS still hangs while loading display.sys.

Any ideas where to look, or are you going to have a look yourself? When
I tried to debug it a while ago, I didn't see anything obvious, but then
I didn't invest that much time for it either.

I haven't tried out any of the other cases described below.

Kevin

> 
> The Windows for Workgroups 3.11 SETUP.EXE file hangs with a cleared
> screen and the cursor blinking in the top left of the screen. The
> DOSIDLE.EXE[1] file hangs after printing out some system
> information.
> 
> Git-Bisecting returned "roms: update vgabios binaries" (commit
> 6eefccc0bb9c34051b1e21880fc3a1c1c8686edd) as the bad commit.
> 
> I tested the i386-softmmu target on Debian 7.3 (wheezy), x86_64 host
> and gcc 4.7.2 (Debian 4.7.2-5) without KVM support.
> 
> [1] Source and binary are available e.g. at
> http://maribu.home.xs4all.nl/zeurkous/download/mirror/dosidle/
> 
> Best Regards,
> Sebastian

Re: [Qemu-devel] WfW setup and DOS display.sys hanging

[Gerd Hoffmann]

[ adding seabios list ]

On Di, 2014-02-04 at 20:47 +0100, Kevin Wolf wrote:
> Hi Gerd,
> 
> Am 09.01.2014 um 00:20 hat Sebastian geschrieben:
> > Hi,
> > 
> > I noticed in newer versions of Qemu (Debian Jessie) a regression
> > causing DISPLAY.SYS from MS-DOS 6.22 to hang the system as soon as
> > loaded.
> 
> now that you sent a pull request for a SeaBIOS update, I tried what
> would happen with this one. Sadly, while it does fix my hanging Win 7
> boot, DOS still hangs while loading display.sys.

[ This is http://www.kraxel.org/cgit/qemu/tag/?id=pull-roms-1
  with the 1.7.4 update ]

Digged out my prehistoric msdos floppy images.  Can confirm the hang.
Using default vga (i.e. cirrus).

Switching back to lgplvgabios ("make -C roms lgplvgabios" in qemu src
tree) makes the hang go away.

> Any ideas where to look, or are you going to have a look yourself? When
> I tried to debug it a while ago, I didn't see anything obvious, but then
> I didn't invest that much time for it either.

"perf kvm stat live" shows tons of NMIs:

             VM-EXIT    Samples  Samples%     Time%   Min Time   Max Time         Avg time 

       EXCEPTION_NMI     660538    99.82%    99.40%        0us      183us      0.67us ( +-   0.14% )
  EXTERNAL_INTERRUPT       1133     0.17%     0.58%        0us       43us      2.25us ( +-   4.86% )
      IO_INSTRUCTION         18     0.00%     0.01%        1us        5us      3.39us ( +-   6.50% )
   PENDING_INTERRUPT         17     0.00%     0.01%        1us       11us      2.15us ( +-  26.24% )

How can one get a trace log of all the kvm tracepoints these days?

'perf list' shows a bunch of kvm trace events,
but "perf trace -e '*kvm*' doesn't show me anything ...

cheers,
  Gerd

> I haven't tried out any of the other cases described below.

[ keeping full quote for seabios list ]

> > 
> > The Windows for Workgroups 3.11 SETUP.EXE file hangs with a cleared
> > screen and the cursor blinking in the top left of the screen. The
> > DOSIDLE.EXE[1] file hangs after printing out some system
> > information.
> > 
> > Git-Bisecting returned "roms: update vgabios binaries" (commit
> > 6eefccc0bb9c34051b1e21880fc3a1c1c8686edd) as the bad commit.
> > 
> > I tested the i386-softmmu target on Debian 7.3 (wheezy), x86_64 host
> > and gcc 4.7.2 (Debian 4.7.2-5) without KVM support.
> > 
> > [1] Source and binary are available e.g. at
> > http://maribu.home.xs4all.nl/zeurkous/download/mirror/dosidle/
> > 
> > Best Regards,
> > Sebastian

Re: [Qemu-devel] [SeaBIOS] WfW setup and DOS display.sys hanging

[Kevin O'Connor]

On Wed, Feb 05, 2014 at 02:19:58PM +0100, Gerd Hoffmann wrote:
> On Di, 2014-02-04 at 20:47 +0100, Kevin Wolf wrote:
> > Hi Gerd,
> > 
> > Am 09.01.2014 um 00:20 hat Sebastian geschrieben:
> > > Hi,
> > > 
> > > I noticed in newer versions of Qemu (Debian Jessie) a regression
> > > causing DISPLAY.SYS from MS-DOS 6.22 to hang the system as soon as
> > > loaded.
> > 
> > now that you sent a pull request for a SeaBIOS update, I tried what
> > would happen with this one. Sadly, while it does fix my hanging Win 7
> > boot, DOS still hangs while loading display.sys.
> 
> [ This is http://www.kraxel.org/cgit/qemu/tag/?id=pull-roms-1
>   with the 1.7.4 update ]
> 
> Digged out my prehistoric msdos floppy images.  Can confirm the hang.
> Using default vga (i.e. cirrus).

I can't reproduce the hang with the dosidle program linked by
Sebastian.  (I ran the program on freedos and on an msdos floppy and
both times it said it install succesfully.)  Can someone walk through
the steps needed to reproduce the problem?

Also, logs from "-chardev stdio,id=seabios -device
isa-debugcon,iobase=0x402,chardev=seabios" would be useful.

-Kevin

Re: [Qemu-devel] [SeaBIOS] WfW setup and DOS display.sys hanging

[Kevin O'Connor]

On Wed, Feb 05, 2014 at 01:34:19PM -0500, Kevin O'Connor wrote:
> On Wed, Feb 05, 2014 at 02:19:58PM +0100, Gerd Hoffmann wrote:
> > On Di, 2014-02-04 at 20:47 +0100, Kevin Wolf wrote:
> > > Hi Gerd,
> > > 
> > > Am 09.01.2014 um 00:20 hat Sebastian geschrieben:
> > > > Hi,
> > > > 
> > > > I noticed in newer versions of Qemu (Debian Jessie) a regression
> > > > causing DISPLAY.SYS from MS-DOS 6.22 to hang the system as soon as
> > > > loaded.
> > > 
> > > now that you sent a pull request for a SeaBIOS update, I tried what
> > > would happen with this one. Sadly, while it does fix my hanging Win 7
> > > boot, DOS still hangs while loading display.sys.
> > 
> > [ This is http://www.kraxel.org/cgit/qemu/tag/?id=pull-roms-1
> >   with the 1.7.4 update ]
> > 
> > Digged out my prehistoric msdos floppy images.  Can confirm the hang.
> > Using default vga (i.e. cirrus).
> 
> I can't reproduce the hang with the dosidle program linked by
> Sebastian.  (I ran the program on freedos and on an msdos floppy and
> both times it said it install succesfully.)  Can someone walk through
> the steps needed to reproduce the problem?

I found some old Win3.1 images, and I do see the failure running setup
on that (when run from dos 6).  I'll look into it.

Sebastian, can you document the steps to reproduce the dosidle and
display.sys failure?  (I tried putting display.sys into a dos6
config.sys, but it doesn't like my parameters so I don't think it's
doing anything.)

-Kevin

Re: [Qemu-devel] [SeaBIOS] WfW setup and DOS display.sys hanging

[Sebastian]

Hi,

>> I can't reproduce the hang with the dosidle program linked by
>> Sebastian.  (I ran the program on freedos and on an msdos floppy and
>> both times it said it install succesfully.)  Can someone walk through
>> the steps needed to reproduce the problem?
>
> I found some old Win3.1 images, and I do see the failure running setup
> on that (when run from dos 6).  I'll look into it.
>
> Sebastian, can you document the steps to reproduce the dosidle and
> display.sys failure?  (I tried putting display.sys into a dos6
> config.sys, but it doesn't like my parameters so I don't think it's
> doing anything.)

I cloned the git repository, and built with:
$ ./configure --target-list=i386-softmmu
$ make -j2

I then installed MS-DOS onto a virtual 50 MB disk, all default settings:
$ /tmp/qemu/i386-softmmu/qemu-system-i386 -m 4 -hda msdos.img -fda 
MS-DOS_1.IMG

After rebooting, qemu hangs with 100% cpu usage when loading 
DISPLAY.SYS. It is loaded by the following line in CONFIG.SYS:

DEVICE=C:\DOS\DISPLAY.SYS CON=(EGA,,1)

Surprisingly, this hang occurs with all of MS-DOS 5.00, 6.20 and 6.22 
(German), but not with a Russian MS-DOS 6.22 (which appears in english). 
I don't have any other language version of DOS to test with, though.

Best Regards,
Sebastian

Re: [Qemu-devel] [SeaBIOS] WfW setup and DOS display.sys hanging

[Kevin O'Connor]

On Wed, Feb 05, 2014 at 09:57:06PM +0100, Sebastian wrote:
> >>I can't reproduce the hang with the dosidle program linked by
> >>Sebastian.  (I ran the program on freedos and on an msdos floppy and
> >>both times it said it install succesfully.)  Can someone walk through
> >>the steps needed to reproduce the problem?
> >
> >I found some old Win3.1 images, and I do see the failure running setup
> >on that (when run from dos 6).  I'll look into it.
> >
> >Sebastian, can you document the steps to reproduce the dosidle and
> >display.sys failure?  (I tried putting display.sys into a dos6
> >config.sys, but it doesn't like my parameters so I don't think it's
> >doing anything.)
> 
> I cloned the git repository, and built with:
> $ ./configure --target-list=i386-softmmu
> $ make -j2
> 
> I then installed MS-DOS onto a virtual 50 MB disk, all default settings:
> $ /tmp/qemu/i386-softmmu/qemu-system-i386 -m 4 -hda msdos.img -fda
> MS-DOS_1.IMG
> 
> After rebooting, qemu hangs with 100% cpu usage when loading
> DISPLAY.SYS. It is loaded by the following line in CONFIG.SYS:
> 
> DEVICE=C:\DOS\DISPLAY.SYS CON=(EGA,,1)

Thanks.  That DEVICE line causes a failure for me as well and the call
trace is much easier to understand.

The SeaVGABIOS patch below fixes both the DISPLAY.SYS and Win3 setup
issue for me.  (I can't reproduce the dosidle problem.)

-Kevin


--- a/vgasrc/vgabios.c
+++ b/vgasrc/vgabios.c
@@ -1114,7 +1114,7 @@ struct funcInfo {
     u8 save_flags;
     u8 disp_info;
     u8 reserved_34[12];
-};
+} PACKED;
 
 static void
 handle_101b(struct bregs *regs)

Re: [Qemu-devel] [SeaBIOS] WfW setup and DOS display.sys hanging

[Gerd Hoffmann]

  Hi,

> Sebastian, can you document the steps to reproduce the dosidle and
> display.sys failure?

Placed a copy of a fresh ms-dos 6.2 install here (qcow2 hard disk
image): http://www.kraxel.org/download/

display.sys hangs reproduces with that image.

cheers,
  Gerd

Re: [Qemu-devel] [SeaBIOS] WfW setup and DOS display.sys hanging

[Kevin O'Connor]

On Thu, Feb 06, 2014 at 09:17:21AM +0100, Gerd Hoffmann wrote:
>   Hi,
> 
> > Sebastian, can you document the steps to reproduce the dosidle and
> > display.sys failure?
> 
> Placed a copy of a fresh ms-dos 6.2 install here (qcow2 hard disk
> image): http://www.kraxel.org/download/
> 
> display.sys hangs reproduces with that image.

Thanks.  I can reproduce this hang, and it looks like the same problem
of handle_101b() missing the PACKED declaration.  It seems fixed with
the "vgabios: Make sure exported structs use PACKED" patch.

-Kevin

Re: [Qemu-devel] [SeaBIOS] WfW setup and DOS display.sys hanging

[Sebastian]

Hi,

>> After rebooting, qemu hangs with 100% cpu usage when loading
>> DISPLAY.SYS. It is loaded by the following line in CONFIG.SYS:
>>
>> DEVICE=C:\DOS\DISPLAY.SYS CON=(EGA,,1)
>
> Thanks.  That DEVICE line causes a failure for me as well and the call
> trace is much easier to understand.
>
> The SeaVGABIOS patch below fixes both the DISPLAY.SYS and Win3 setup
> issue for me.  (I can't reproduce the dosidle problem.)

The attached patch does indeed fix both the DISPLAY.SYS and Windows 
Setup problems for me. Thanks a lot! I can't reproduce the 
dosidle-problem either, it works now.

A straight non-networked Windows for Workgroups 3.11 installation now 
hangs after loading the Program Manager.

I noticed that SeaBIOS does not work correctly with parallel make, log 
excerpts following:

$ LANG=C make -j16 # dual-core machine without SMT
   Compiling IASL out/src/fw/acpi-dsdt.hex
make[1]: warning: jobserver unavailable: using -j1.  Add `+' to parent 
make rule.
   Compiling IASL out/src/fw/ssdt-proc.hex
   Compiling IASL out/src/fw/ssdt-pcihp.hex

[...]

Compilation complete. 0 Errors, 0 Warnings, 0 Remarks, 2 Optimizations
   Generating offset file out/asm-offsets.h
   Compiling (16bit) out/romlayout.o
In file included from src/romlayout.S:9:0:
src/config.h:4:22: fatal error: autoconf.h: No such file or directory
compilation terminated.
make: *** [out/romlayout.o] Error 1
make: *** Waiting for unfinished jobs....
ASL Input:  out/src/fw/q35-acpi-dsdt.dsl.i - 515 lines, 28284 bytes, 413 
keywords
AML Output: out/src/fw/q35-acpi-dsdt.aml - 7344 bytes, 239 named 
objects, 174 executable opcodes

Compilation complete. 0 Errors, 0 Warnings, 0 Remarks, 445 Optimizations
   Build Kconfig config file
$

Best Regards,
Sebastian

Re: [Qemu-devel] [SeaBIOS] WfW setup and DOS display.sys hanging

[Kevin O'Connor]

On Mon, Feb 10, 2014 at 03:57:46PM +0100, Sebastian wrote:
> Hi,
> 
> >>After rebooting, qemu hangs with 100% cpu usage when loading
> >>DISPLAY.SYS. It is loaded by the following line in CONFIG.SYS:
> >>
> >>DEVICE=C:\DOS\DISPLAY.SYS CON=(EGA,,1)
> >
> >Thanks.  That DEVICE line causes a failure for me as well and the call
> >trace is much easier to understand.
> >
> >The SeaVGABIOS patch below fixes both the DISPLAY.SYS and Win3 setup
> >issue for me.  (I can't reproduce the dosidle problem.)
> 
> The attached patch does indeed fix both the DISPLAY.SYS and Windows
> Setup problems for me. Thanks a lot! I can't reproduce the
> dosidle-problem either, it works now.

Okay, I hae pushed that patch into mainline.

> A straight non-networked Windows for Workgroups 3.11 installation
> now hangs after loading the Program Manager.

Is that related to seabios?

> I noticed that SeaBIOS does not work correctly with parallel make,
> log excerpts following:

I'll take a look if I get a chance.

-Kevin