From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Perches <joe-6d6DIl74uiNBDgjK7y7TUQ@public.gmane.org>
Subject: Re: [PATCH v4 0/3] mm, treewide: Rename kzfree() to
 kfree_sensitive()
Date: Tue, 16 Jun 2020 11:53:50 -0700
Message-ID: <fe3b9a437be4aeab3bac68f04193cb6daaa5bee4.camel@perches.com>
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To: Waiman Long <longman-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, David Howells <dhowells-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Jarkko Sakkinen <jarkko.sakkinen-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>, James Morris <jmorris-gx6/JNMH7DfYtjvyW6yDsg@public.gmane.org>, "Serge E. Hallyn" <serge-A9i7LUbDfNHQT0dZR+AlfA@public.gmane.org>, Linus Torvalds <torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, Matthew Wilcox <willy-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, David Rientjes <rientjes-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
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List-Id: virtualization@lists.linuxfoundation.org

On Mon, 2020-06-15 at 21:57 -0400, Waiman Long wrote:
>  v4:
>   - Break out the memzero_explicit() change as suggested by Dan Carpenter
>     so that it can be backported to stable.
>   - Drop the "crypto: Remove unnecessary memzero_explicit()" patch for
>     now as there can be a bit more discussion on what is best. It will be
>     introduced as a separate patch later on after this one is merged.

To this larger audience and last week without reply:
https://lore.kernel.org/lkml/573b3fbd5927c643920e1364230c296b23e7584d.camel-6d6DIl74uiNBDgjK7y7TUQ@public.gmane.org/

Are there _any_ fastpath uses of kfree or vfree?

Many patches have been posted recently to fix mispairings
of specific types of alloc and free functions.

To eliminate these mispairings at a runtime cost of four
comparisons, should the kfree/vfree/kvfree/kfree_const
functions be consolidated into a single kfree?

Something like the below:

   void kfree(const void *addr)
   {
   	if (is_kernel_rodata((unsigned long)addr))
   		return;

   	if (is_vmalloc_addr(addr))
   		_vfree(addr);
   	else
   		_kfree(addr);
   }

   #define kvfree		kfree
   #define vfree		kfree
   #define kfree_const	kfree