[PATCH] forthstrap: avoid unaligned accesses

[Aurelien Jarno]

Trying to compile OpenBIOS for SPARC32 on a SPARC machine, I get a
SIGBUS within forthstrap, more precisely accessing reloc_table in
load_dictionary. This table is not aligned because the dictionnary
head as a size which is not a multiple of 4.

This is due to the file QEMU,tcx.bin which is being encoded, and which
has a size which is not a multiple of 4. Fix that by adding some padding
after the encoded data.
---
 kernel/bootstrap.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/bootstrap.c b/kernel/bootstrap.c
index 546ffee..7f4458e 100644
--- a/kernel/bootstrap.c
+++ b/kernel/bootstrap.c
@@ -1008,6 +1008,7 @@ encode_file( const char *name )
    PUSH( pointer2cell(dict + dicthead) );
    PUSH( size );
    dicthead += size;
+	paddict(sizeof(cell));
 }

[Mark Cave-Ayland]

On 08/12/13 10:53, Aurelien Jarno wrote:
> Trying to compile OpenBIOS for SPARC32 on a SPARC machine, I get a
> SIGBUS within forthstrap, more precisely accessing reloc_table in
> load_dictionary. This table is not aligned because the dictionnary
> head as a size which is not a multiple of 4.
>
> This is due to the file QEMU,tcx.bin which is being encoded, and which
> has a size which is not a multiple of 4. Fix that by adding some padding
> after the encoded data.
>
> kernel/bootstrap.c | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/kernel/bootstrap.c b/kernel/bootstrap.c
> index 546ffee..7f4458e 100644
> --- a/kernel/bootstrap.c
> +++ b/kernel/bootstrap.c
> @@ -1008,6 +1008,7 @@ encode_file( const char *name )
>    PUSH( pointer2cell(dict + dicthead) );
>    PUSH( size );
>    dicthead += size;
> paddict(sizeof(cell));
> }

Hi Aurelien,

This patch looks good to me - if you can resubmit with a SOB line then 
I'm happy to apply it.

ATB,

Mark.

[Aurelien Jarno]

On Sun, Dec 08, 2013 at 11:51:13AM +0000, Mark Cave-Ayland wrote:
> On 08/12/13 10:53, Aurelien Jarno wrote:
> > Trying to compile OpenBIOS for SPARC32 on a SPARC machine, I get a
> > SIGBUS within forthstrap, more precisely accessing reloc_table in
> > load_dictionary. This table is not aligned because the dictionnary
> > head as a size which is not a multiple of 4.
> >
> > This is due to the file QEMU,tcx.bin which is being encoded, and which
> > has a size which is not a multiple of 4. Fix that by adding some padding
> > after the encoded data.
> >
> > kernel/bootstrap.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/kernel/bootstrap.c b/kernel/bootstrap.c
> > index 546ffee..7f4458e 100644
> > --- a/kernel/bootstrap.c
> > +++ b/kernel/bootstrap.c
> > @@ -1008,6 +1008,7 @@ encode_file( const char *name )
> >    PUSH( pointer2cell(dict + dicthead) );
> >    PUSH( size );
> >    dicthead += size;
> > paddict(sizeof(cell));
> >
> > }
>
> Hi Aurelien,
>
> This patch looks good to me - if you can resubmit with a SOB line
> then I'm happy to apply it.

Thanks I have just send it.

Best regards,
Aurelien

[Mark Cave-Ayland]

On 08/12/13 12:26, Aurelien Jarno wrote:
> On Sun, Dec 08, 2013 at 11:51:13AM +0000, Mark Cave-Ayland wrote:
> > On 08/12/13 10:53, Aurelien Jarno wrote:
> > > Trying to compile OpenBIOS for SPARC32 on a SPARC machine, I get a
> > > SIGBUS within forthstrap, more precisely accessing reloc_table in
> > > load_dictionary. This table is not aligned because the dictionnary
> > > head as a size which is not a multiple of 4.
> > >
> > > This is due to the file QEMU,tcx.bin which is being encoded, and which
> > > has a size which is not a multiple of 4. Fix that by adding some padding
> > > after the encoded data.
> > >
> > > kernel/bootstrap.c | 1 +
> > >   1 file changed, 1 insertion(+)
> > >
> > > diff --git a/kernel/bootstrap.c b/kernel/bootstrap.c
> > > index 546ffee..7f4458e 100644
> > > --- a/kernel/bootstrap.c
> > > +++ b/kernel/bootstrap.c
> > > @@ -1008,6 +1008,7 @@ encode_file( const char *name )
> > >    PUSH( pointer2cell(dict + dicthead) );
> > >    PUSH( size );
> > >    dicthead += size;
> > > paddict(sizeof(cell));
> > > }
> >
> > Hi Aurelien,
> >
> > This patch looks good to me - if you can resubmit with a SOB line
> > then I'm happy to apply it.
>
> Thanks I have just send it.
>
> Best regards,
> Aurelien

Hi Aurelien,

Looks good to me - applied to SVN trunk. Thanks a lot!

ATB,

Mark.