Re: [Qemu-devel] [PATCH] Disable AIO for Mac OS X

[Alexander Graf]

On 24.01.2009, at 21:53, Anthony Liguori wrote:

> Alexander Graf wrote:
> > On 24.01.2009, at 21:28, Anthony Liguori wrote:
> >
> > > Alexander Graf wrote:
> > > > While trying current svn, it looks like AIO support compiles on
> > > > Mac OS X finally. Unfortunately it is broken and as soon as I want
> > > > to run any image, it endless loops in block.c:1446 which is:
> > > >
> > > >   while (async_ret == NOT_DONE) {
> > > >       qemu_aio_wait();
> > > >   }
> > >
> > > Are you using cocoa?
> >
> > Yep. Nothing else works for x86_64 on Mac OS X ;-). Well - except  
> > for vnc.
> >
> > > I don't think the AIO code is broken here.  I think something else  
> > > is broken and disabling AIO hides the symptom.  Can you dig more  
> > > into this?
> >
> > Hum - sounds like an idea. I'm open for hints on how to dig in  
> > here. I can disable cocoa for starters of course.
>
> My guess would be that the completion signal isn't being delivered.   
> I'd start by disabling cocoa and then annotate things to see if the  
> completion signal every makes it to the aio system.

So disabling cocoa doesn't really help. I recompiled with cocoa=no and  
still have the same issue:

(gdb) thread apply all bt

Thread 1 (process 38766 thread 0x10b):
#0  0x91b846f2 in select$DARWIN_EXTSN ()
#1  0x00081526 in qemu_aio_wait () at aio.c:158
#2  0x00081055 in bdrv_read_em (bs=0x4, sector_num=0, buf=0x4 <Address  
0x4 out of bounds>, nb_sectors=4) at block.c:1447
#3  0x0007fb29 in bdrv_guess_geometry (bs=0x806a00, pcyls=0xbfffdfcc,  
pheads=0xbfffdfc8, psecs=0xbfffdfc4) at block.c:773
#4  0x0002a398 in ide_init2 (ide_state=<value temporarily unavailable,  
due to optimizations>, hd0=0x806a00, hd1=0x0, irq=0x402a18) at /Users/ 
alex/work/qemu-osx/qemu/hw/ide.c:2844
#5  0x0002b08d in pci_piix3_ide_init (bus=0x4, hd_table=0xbfffeaf0,  
devfn=4, pic=0x402930) at /Users/alex/work/qemu-osx/qemu/hw/ide.c:3435
#6  0x000442f9 in pc_init1 (ram_size=<value temporarily unavailable,  
due to optimizations>, vga_ram_size=8388608, boot_device=0x11da16  
"cad", kernel_filename=0x0, kernel_cmdline=0x11d40c "",  
initrd_filename=0x0, pci_enabled=1, cpu_model=0x0) at /Users/alex/work/ 
qemu-osx/qemu/hw/pc.c:1027
#7  0x000068d1 in main (argc=5, argv=0xbffff360, envp=0xbffff378) at / 
Users/alex/work/qemu-osx/qemu/vl.c:5520

It's actually hanging in its first select() call.

Alex

> Regards,
>
> Anthony Liguori
>
> > Alex
> >
> > > Regards,
> > >
> > > Anthony Liguori
> > >
> > > > So for the time being, let's simply disable aio for Mac OS X.
> > > >
> > > > Signed-off-by: Alexander Graf <address@hidden>
> > > > ---
> > > > configure |    1 +
> > > > 1 files changed, 1 insertions(+), 0 deletions(-)
> > > >
> > > > diff --git a/configure b/configure
> > > > index c3fbbbe..3e701b9 100755
> > > > --- a/configure
> > > > +++ b/configure
> > > > @@ -259,6 +259,7 @@ cocoa="yes"
> > > > audio_drv_list="coreaudio"
> > > > audio_possible_drivers="coreaudio sdl fmod"
> > > > OS_LDFLAGS="-framework CoreFoundation -framework IOKit"
> > > > +aio="no"
> > > > ;;
> > > > SunOS)
> > > >    solaris="yes"