Re: [PATCH] flush_cache_page while pte valid

David S. Miller
2002-11-12T06:48:27Z

From: Hugh Dickins <hugh@veritas.com>
Date: Tue, 12 Nov 2002 06:53:04 +0000 (GMT)

Thanks for shedding light on that; but I'm still wondering if there
might be data loss if userspace modifies the page in the tiny window
between correctly positioned flush_cache_page and pte invalidation?

The flush merely writes back the data, a copy-back operation, fully L2
cache coherent. All cpus will see correct data if an intermittant
store occurs.