Infinite loop regression due to recent change in hostfs.c

Infinite loop regression due to recent change in hostfs.c

[Christian Franke]

Pavel Roskin wrote:
> ...
> Log message:
> 	2008-03-30  Pavel Roskin  <...>
> 	
> 		* disk/host.c: Include grub/misc.h to fix a warning.
> 		* util/hostfs.c: Use GRUB_MOD_INIT and GRUB_MOD_FINI to fix
> 		warnings about implicit declarations.
>
> CVSWeb URLs:
> http://cvs.savannah.gnu.org/viewcvs/grub2/ChangeLog?cvsroot=grub&r1=1.618&r2=1.619
> http://cvs.savannah.gnu.org/viewcvs/grub2/disk/host.c?cvsroot=grub&r1=1.2&r2=1.3
> http://cvs.savannah.gnu.org/viewcvs/grub2/util/hostfs.c?cvsroot=grub&r1=1.4&r2=1.5

The change in hostfs.c introduces an interesting regression: hostfs now appears in *_init.lst and grub_hostfs_init() is called twice in grub-emu and grub-fstest. This results in a infinite loop because the hostfs entry of grub_fs_list points to itself.

Demo version :-)

$ grub-fstest -d all /dev/sdX ls -l | grep Detecting | head -10000 | uniq -c

You should either undo this change or remove extra calls to grub_hostfs_init/fini from grub-emu.c and grub-fstest.c. The latter might not work if it is necessary to init hostfs first for some reason.

Christian

Re: Infinite loop regression due to recent change in hostfs.c

[Pavel Roskin]

Quoting Christian Franke <Christian.Franke@t-online.de>:

> The change in hostfs.c introduces an interesting regression: hostfs now
> appears in *_init.lst and grub_hostfs_init() is called twice in
> grub-emu and grub-fstest. This results in a infinite loop because the
> hostfs entry of grub_fs_list points to itself.

Thanks for noticing the problem and for the analysis!

> You should either undo this change or remove extra calls to
> grub_hostfs_init/fini from grub-emu.c and grub-fstest.c. The latter
> might not work if it is necessary to init hostfs first for some reason.

I've removed the extra calls.  I don't see any reasons why hostfs  
should be registered first.

-- 
Regards,
Pavel Roskin

Re: Infinite loop regression due to recent change in hostfs.c

[Christian Franke]

Pavel Roskin wrote:
> Quoting Christian Franke <...>:
>
>> You should either undo this change or remove extra calls to
>> grub_hostfs_init/fini from grub-emu.c and grub-fstest.c. The latter
>> might not work if it is necessary to init hostfs first for some reason.
>
> I've removed the extra calls.  I don't see any reasons why hostfs 
> should be registered first.
>

It now works as expected.

Christian

Re: Infinite loop regression due to recent change in hostfs.c

[Robert Millan]

On Sun, Apr 06, 2008 at 01:21:31PM -0400, Pavel Roskin wrote:
> Quoting Christian Franke <Christian.Franke@t-online.de>:
> 
> >The change in hostfs.c introduces an interesting regression: hostfs now
> >appears in *_init.lst and grub_hostfs_init() is called twice in
> >grub-emu and grub-fstest. This results in a infinite loop because the
> >hostfs entry of grub_fs_list points to itself.
> 
> Thanks for noticing the problem and for the analysis!
> 
> >You should either undo this change or remove extra calls to
> >grub_hostfs_init/fini from grub-emu.c and grub-fstest.c. The latter
> >might not work if it is necessary to init hostfs first for some reason.
> 
> I've removed the extra calls.  I don't see any reasons why hostfs  
> should be registered first.

I suspect it was a remnant from before we had grub_init_all().

-- 
Robert Millan

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