Re: [PATCH v2] core, x86: Add user return notifiers

From: Peter Zijlstra
Date: Tue Sep 22 2009 - 14:07:27 EST


On Tue, 2009-09-22 at 16:32 +0200, Ingo Molnar wrote:

> Would be nice to convert some existing open-coded return-to-user-space
> logic to this facility. One such candidate would be lockdep_sys_exit?

I don't really like lockdep_sys_exit() in such a call,
lockdep_sys_exit() is currently placed such that it will execute as the
last C code before returning to user-space.

Put it any earlier and you've got a window where people can leak a lock
to userspace undetected.

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