On Fri, 13 Oct 2006, Andrew Morton wrote: > On Fri, 13 Oct 2006 15:11:11 +0200 > Helge Hafting <[EMAIL PROTECTED]> wrote: > > > Andrew Morton wrote: > > > On Thu, 12 Oct 2006 14:18:04 +0200 > > > Helge Hafting <[EMAIL PROTECTED]> 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?
Verbose usb-storage debugging messages would help more (CONFIG_USB_STORAGE_DEBUG and CONFIG_USB_DEBUG). If the kernel hangs very badly you might need to use a serial console to capture all the logging information. Alan Stern ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
