[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]
Re: kern/42573: DIRBLKSIZ in <ufs/ufs/dir.h> should not beDEV_BSIZE constant
The following reply was made to PR kern/42573; it has been noted by GNATS.
From: Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>
Cc: kern-bug-people%NetBSD.org@localhost, gnats-admin%NetBSD.org@localhost,
Subject: Re: kern/42573: DIRBLKSIZ in <ufs/ufs/dir.h> should not beDEV_BSIZE
Date: Mon, 4 Jan 2010 09:17:06 +0900
> > > But to make everything fit (eg i386 boot code) the byte alignments
> > > cannot change - the label has to remain in bytes 512-1203.
> > Does it? What about "LABELSECTOR" in <machine/disklabel.h>?
> LABELSECTOR needs to go.
Hmm, how can you fix sys/kern/subr_disk_mbr.c without it?
> > Shouldn't sys/arch/i386/stand/mbr/mbr.S be sector size aware?
> I think that code is safe - even though it will read rather more data
> than expected.
> What happens later on is a bigger problem.
The problem is that current bootloader code assume sector size is 512.
I wonder if we should keep such assumption even on !512byte/sector disks.
> > > (I have a USB memory stick with 2k sectors, the 0x55, 0xaa are in
> > > bytes 510 and 511 as usual.)
> > Magic should be at MBR_MAGIC_OFFSET defined in <sys/bootblock.h>
> > so it doesn't matter of sector size, does it?
> No - NetBSD doesn't have control over the mbr layout.
> We have to match what (probably) microsoft does.
Anyway, file a new PR about it. This PR is about DIRBLKSIZ,
just one of a bunch of !512byte/sector problems.
Main Index |
Thread Index |