Messages in this thread | | | Date | Thu, 9 Oct 2008 14:23:19 +0200 | From | Pavel Machek <> | Subject | Re: [RESEND] [PATCH] VFS: make file->f_pos access atomic on 32bit arch |
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On Tue 2008-10-07 20:52:09, Matthew Wilcox wrote: > On Wed, Oct 08, 2008 at 01:35:44PM +1100, Nick Piggin wrote: > > Right you are. That's the fundamental question. The actual details of > > the fix and how likely the race is don't really matter until we > > answer the first question (except to say that the "fix" is never going > > to be free). > > > > We've lasted this long with the current semantics. So the natural > > reaction to anything that strengthens the semantics now is "why?". If > > we do that then we can basically never return to the weaker semantics. > > So there had better be a really good reason. > > And it's worth saying that letter-of-the-standard arguments aren't > necessarily enough. Linux does not honour the POSIX guarantee that > writes are atomic (if they cross page boundaries, it's not certain). > This seems like even more of a corner case to me.
We have append-only files, and normal users should not be able to work around that restriction. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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