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From: Mikael Pettersson <mikpe@user.it.uu.se>
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Date: Tue, 11 Mar 2003 13:59:21 +0100
To: Linus Torvalds <torvalds@transmeta.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [BK-2.5] Move "used FPU status" into new non-atomic thread_info->status
 field.
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Linus Torvalds writes:
 > > Sorry for being dense, but can you clarify: will current 2.{2,4,5}
 > > kernels preserve or destroy the parent process' FPU control at fork()?
 > 
 > They're guaranteed to preserve the control state (it has to: you can't 
 > just change the exception mask over a function call). However, that was 
 > buggy at least in 2.5.x, and very possibly in 2.4.x too - haven't checked.

Thanks. Our use of unmasked FPU exceptions should be safe then, unless
2.4 also has the bug you fixed in 2.5.

/Mikael
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