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Date: Sat, 13 Dec 2003 11:41:34 +0000
To: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Subject: Possible shared mapping bug in 2.4.23 (at least MIPS/Sparc)
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From: Peter Horton <pdh@colonel-panic.org>
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The current MIPS 2.4 kernel (from CVS) currently allows fixed shared
mappings to violate D-cache aliasing constraints.

The check for illegal fixed mappings is done in
arch_get_unmapped_area(), but these mappings are granted in
get_unmapped_area() and arch_get_unmapped_area() is never called.

A quick look at sparc and sparc64 seem to show the same problem.

P.