lkml.org 
[lkml]   [2006]   [Oct]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: 2.6.19-rc1-mm1 - locks when using "dd bs=1M" from card reader
On Fri, 13 Oct 2006 15:11:11 +0200
Helge Hafting <helge.hafting@aitel.hist.no> wrote:

> Andrew Morton wrote:
> > On Thu, 12 Oct 2006 14:18:04 +0200
> > Helge Hafting <helge.hafting@aitel.hist.no> wrote:
> >
> >
> >> I found an easy way to hang the kernel when copying a SD-card:
> >>
> >> dd if=/dev/sdc of=file bs=1048576
> >>
> >> I.e. copy the entire 256MB card in 1MB chunks. I got about
> >> 160MB before the kernel hung. Not even sysrq+B worked, I needed
> >> the reset button. The pc has a total of 512MB memory if that matters.
> >>
> >> Using bs=4096 instead let me copy the entire card with no problems,
> >> but that seems to progress slower.
> >>
> >> The above 'dd' command hangs my office pc every time. So I can repeat
> >> it for debugging purposes.
> >>
> >>
> >
> > What device driver is providing /dev/sdc?
> >
> It is an usb card reader, so it is "usb mass storage"
> and "scsi disk".
> > Did any previous kernels work correctly? If so, which?
> >
>
> I just got that card reader, so I haven't tested any earlier kernels.
> I have another machine with a card reader, which I have used for
> a long time. But I only ever copy files with "cp" on that one.
>
> This time I used "dd" to get an image of the entire card, and got trouble
> when using 1M chunks.
>
> I can try with verbose scsi debug messages if that might help?
>

Maybe. The first step is to tell the developers. (adds cc).

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-10-13 18:33    [from the cache]
©2003-2011 Jasper Spaans