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Date: Mon, 8 Feb 2016 13:48:32 +1100
From: Paul Mackerras <paulus@ozlabs.org>
To: David Gibson <david@gibson.dropbear.id.au>
Cc: mpe@ellerman.id.au, benh@kernel.crashing.org,
 linuxppc-dev@lists.ozlabs.org, aik@ozlabs.ru, thuth@redhat.com,
 lvivier@redhat.com
Subject: Re: [RFCv2 2/9] arch/powerpc: Clean up error handling for
 htab_remove_mapping
Message-ID: <20160208024832.GB30807@oak.ozlabs.ibm.com>
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On Fri, Jan 29, 2016 at 04:23:56PM +1100, David Gibson wrote:
> Currently, the only error that htab_remove_mapping() can report is -EINVAL,
> if removal of bolted HPTEs isn't implemeted for this platform.  We make
> a few clean ups to the handling of this:
> 
>  * EINVAL isn't really the right code - there's nothing wrong with the
>    function's arguments - use ENODEV instead
>  * We were also printing a warning message, but that's a decision better
>    left up to the callers, so remove it
>  * One caller is vmemmap_remove_mapping(), which will just BUG_ON() on
>    error, making the warning message irrelevant, so no change is needed
>    there.
>  * The other caller is remove_section_mapping().  This is called in the
>    memory hot remove path at a point after vmemmap_remove_mapping() so
>    if hpte_removebolted isn't implemented, we'd expect to have already
>    BUG()ed anyway.  Put a WARN_ON() here, in lieu of a printk() since this
>    really shouldn't be happening.
> 
> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Reviewed-by: Paul Mackerras <paulus@samba.org>