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Date: Sat, 23 Dec 2000 18:15:41 +0530 (IST)
From: Sourav Sen <sourav@csa.iisc.ernet.in>
To: lkml <linux-kernel@vger.kernel.org>
Subject: why both kernel lock as well as semaphore
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In many parts of the kernel, I have seen both semaphore is taken
(eg. down(&current->mm->mmap_sem)) as well as kernel lock (lock_kernel())
is also taken, why both are required? Whats the purpose of each?

~sourav

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