[bug #32472] GRUB2 does not flush data correctly after installing

[КоренбергМарк]

URL:
  <http://savannah.gnu.org/bugs/?32472>

                 Summary: GRUB2 does not flush data correctly after installing
                 Project: GNU GRUB
            Submitted by: socketpair
            Submitted on: Пнд 14 Фев 2011 09:31:27
                Category: Installation
                Severity: Major
                Priority: 5 - Normal
              Item Group: Software Error
                  Status: None
                 Privacy: Public
             Assigned to: None
         Originator Name: Коренберг Марк
        Originator Email: address@hidden
             Open/Closed: Open
         Discussion Lock: Any
                 Release: 
                 Release: 1.98
         Reproducibility: Every Time
         Planned Release: None

    _______________________________________________________

Details:

It is safer to call fsync() on FD connected to device [flush kernel cache].
After which, ioctl(BLKFLSBUF) should follow [flush hardware cache]. This
sequence guaranteed data flushing.

Now, GRUB only call sync() which does nothing.

In Linux, sync() has influence only to data written to file on a filesystem.
Embedding GRUB into first sectors is not such case, so sync() will not work as
expected, redundant, and also have performance issues (this call will blocked
until all current and ongoing data on another drive will be written, so
installing GRUB on massively used server may take much time)




    _______________________________________________________

Reply to this item at:

  <http://savannah.gnu.org/bugs/?32472>

_______________________________________________
  Message sent via/by Savannah
  http://savannah.gnu.org/