system hangs during unmounting

s_sitaraman_at_hotmail.com
Date: 10/24/05

  • Next message: s_sitaraman_at_hotmail.com: "Re: system hangs during unmounting" 
    Date: 23 Oct 2005 16:24:34 -0700

    I am implementing a tool in the kernel which taps a block write to a
    specific mounted partition (say, /dev/hda6, the source disk) and makes
    a copy of this block of data to an unmounted disk (say, /dev/hdb1 or a
    DVD, the archive disk). To do this in kernel space, I open the archive
    disk as a raw device file, and invoke the function
    fdesc->f_op->write(...). In order to successfully write to the archive
    disk, I have to set the FS register to kernel space, and set the uid
    and gid to 0(root). After the write is done, I reset these values to
    what they were originally.

    Concurrently, when I try to unmount the source disk partition,
    /dev/hda6, the whole system hangs. The unmount is successful when the
    setting and resetting of the FS register, uid, and gid are not done.
    But in that case the disk write to the archive disk is not successful.

    Any help is appreciated!

    Thanks!

  • Next message: s_sitaraman_at_hotmail.com: "Re: system hangs during unmounting"

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