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Message-ID: <44B36910.3010801@lsrfire.ath.cx>
Date: Tue, 11 Jul 2006 11:02:08 +0200
From: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
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To: Andrew Morton <akpm@osdl.org>
CC: linux-kernel@vger.kernel.org, devel@openvz.org, kuznet@ms2.inr.ac.ru,
       Linus Torvalds <torvalds@osdl.org>
Subject: Re: [PATCH] fdset's leakage
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[strange loop snipped]

> That's going to take a long time to compute if nr > NR_OPEN.  I just fixed
> a similar infinite loop in this function.

That other fix looks buggy btw.  Here it is:

-	nfds = 8 * L1_CACHE_BYTES;
-  	/* Expand to the max in easy steps */
-  	while (nfds <= nr) {
-		nfds = nfds * 2;
-		if (nfds > NR_OPEN)
-			nfds = NR_OPEN;
-	}
+	nfds = max_t(int, 8 * L1_CACHE_BYTES, roundup_pow_of_two(nfds));
+	if (nfds > NR_OPEN)
+		nfds = NR_OPEN;

Surely you meant to say "roundup_pow_of_two(nr + 1)"?

René