On Fri, 6 Dec 2002, Martin Maletinsky wrote:

After getting the corresponding page table entry, the function makes a
check, which I don't quite understand - if write access is requested to
the page, it not only checks the write permission in the page table
entry (with pte_write()), but also the dirty bit (with pte_dirty()). Why
does a page need to be dirty in the case write == 1 (see line 444 in the
code excerpt below?

If write == 1, then somebody wants to write to the page NOW.
In that case it's more efficient to just set the dirty bit
than to take a trap later on; remember that many CPUs can't
keep track of the dirty bit in hardware but trap to the OS.

Rik
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A: No.
Q: Should I include quotations after my reply?
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