From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nick Piggin <npiggin@suse.de>
Subject: Re: [PATCH 00/22] HWPOISON: Intro (v5)
Date: Mon, 15 Jun 2009 10:14:53 +0200
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Cc: Balbir Singh <balbir@linux.vnet.ibm.com>,
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To: Wu Fengguang <fengguang.wu@intel.com>
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On Mon, Jun 15, 2009 at 08:44:47AM +0200, Nick Piggin wrote:
> Did we verify with filesystem maintainers (eg. btrfs) that the
> !ISREG test will be enough to prevent oopses?

BTW. this is quite a significant change I think and not
really documented well enough. Previously a filesystem
will know exactly when and why pagecache in a mapping
under its control will be truncated (as opposed to
invalidated).

They even have opportunity to hold locks such as i_mutex.

And depending on what they do, they could do interesting
things even with ISREG files.

So, I really think this needs review by filesystem
maintainers and it would be far safer to use invalidate
until it is known to be safe.