From owner-freebsd-net@FreeBSD.ORG  Fri Sep 19 18:51:39 2008
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Date: Fri, 19 Sep 2008 11:31:57 -0700
From: Renaud Lienhart <renaud@vmware.com>
To: freebsd-net@freebsd.org
Message-ID: <20080919113157.2ac9fe9e@renaud-dev1.eng.vmware.com>
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Cc: stolarchuk@vmware.com
Subject: Unnecessary check in mb_zinit_pack()?
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It seems there is a redundant check in mb_zinit_pack():

	if (uma_zalloc_arg(zone_clust, m, how) == NULL ||
	    m->m_ext.ext_buf == NULL)
		return (ENOMEM);

If uma_zalloc_arg() successfully allocates a cluster then shouldn't
m->m_ext.ext_buf be guaranteed not to be NULL?

I can't find any rationale for the second check; I removed it from my
private tree, moved it into a KASSERT() and didn't run into any problem
so far.

Am I missing something?

Thanks,

	Renaud Lienhart