Re: BUG? atleast >=2.6.19-rc5, x86 chroot on x86_64

[Chuck Ebbert <76306.1226@compuserve.com>]

In-Reply-To: <4701.1165328393@redhat.com>

On Tue, 05 Dec 2006 14:19:53 +0000, David Howells wrote:
> > Here is a patch to reverse that.  Kasper, can you test it?
> > (Your filesystem is on a FAT/VFAT volume, I assume.)
> 
> Please don't revert that patch.  If you do, you'll break CONFIG_BLOCK=n.
> 
> Can you compile and run the attached program as both 32-bit and 64-bit?

I only have 32-bit userspace.  When I run your program against
a directory on a JFS filesystem (msdos ioctls not supported)
I get this on vanilla 2.6.19:

$ ./vfat_ioctl32.ex .
268 : 82187201, 82187202
268 : 82187201, 82187202
Calling VFAT_IOCTL_READDIR_BOTH32
ioctl: Invalid argument
Calling VFAT_IOCTL_READDIR_BOTH
ioctl: Invalid argument

After reverting the msdos compat ioctls patch it changes to:

$ ./vfat_ioctl32.ex .
268 : 82187201, 82187202
268 : 82187201, 82187202
Calling VFAT_IOCTL_READDIR_BOTH32
ioctl: Inappropriate ioctl for device
Calling VFAT_IOCTL_READDIR_BOTH
ioctl: Inappropriate ioctl for device

> | i have only tested with >=rc5, thw folling, as an example, appears in
> | dmesg:
> | ioctl32(regedit.exe:11801): Unknown cmd fd(9) cmd(82187201){02}
> | arg(00221000) on /home/redeeman
> | ioctl32(regedit.exe:11801): Unknown cmd fd(9) cmd(82187201){02}
> | arg(00221000) on /home/redeeman/.wine/drive_c/windows/system32
> | ioctl32(regedit.exe:11801): Unknown cmd fd(9) cmd(82187201){02}
> | arg(00221000) on /home/redeeman/.wine/drive_c/windows/system
> 
> How do you get that? 

I get those messages when the ioctl call returns 'invalid argument.'

In fs/compat.s::compat_sys_ioctl() you can see it changing the
return value after it prints the message:

                static int count;

                if (++count <= 50)
                        compat_ioctl_error(filp, fd, cmd, arg);
                error = -EINVAL;

So apparently this is a feature?

-- 
Chuck
"Even supernovas have their duller moments."