Re: the >1Tb block issue

[Gleb Natapov <gleb@redhat.com>]

On Tue, May 18, 2010 at 08:51:55PM +0400, Michael Tokarev wrote:
> 18.05.2010 19:52, Michael Tokarev wrote:
> >I just re-verified it on current stable
> >qemu-kvm-0.12.4. The issue is still here,
> >trivial to trigger.
> >
> >kvm-img create test.raw 1500G
> >kvm ... \
> >-drive file=test.raw,if=virtio
> >
> >it fails right on the mkfs stage:
> >
> >mkfs.ext4 /dev/vdb
> >Writing inode tables: end_request: I/O error, dev vdb, sector 3145727872
> >Buffer I/O error on device vdb, logical block 393215984
> >lost page write due to I/O error on vdb
> >Buffer I/O error on device vdb, logical block 393215985
> >...
> >Buffer I/O error on device vdb, logical block 393215993
> >
> >After that it continues the mkfs process, but I doubt it will
> >produce a good filesystem.
> 
> A few more data point, for what it's worth.
> 
> I tried running it under strace, but in that case the issue does
> not occur: mkfs wents on without errors.  That puzzles me: timing
> problem?
> 
> It always fails at the same place: sector 3145727872. This
> is - apparently - somewhere at the end of my 1500Gb file.
> 
Hmmm. 3145727872*512 = 0xffff0000

--
			Gleb.