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Re: PG_locked flag and MAP_SHARED

On Tue, 2005-03-01 at 05:19 -0800, arvind k wrote:
> Hi All,
> 
> I understand that PG_locked flag is set in page->flags
> before initiating I/O on a page to avoid parallel
> I/Os. But I am wondering how we avoid other processes
> and threads from accessing the same page in userspace
> if it is mapped(MAP_SHARED) to the address space of
> multiple processes.

we don't... and that's ok
what will happen is that the writes those processes do get written out 
again later anyway, so there's no data loss involved...



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