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 for <linuxppc-dev@lists.ozlabs.org>; Mon,  8 Feb 2016 16:47:19 +1100 (AEDT)
Date: Mon, 8 Feb 2016 16:47:03 +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 4/9] arch/powerpc: Clean up memory hotplug failure paths
Message-ID: <20160208054703.GD30807@oak.ozlabs.ibm.com>
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On Fri, Jan 29, 2016 at 04:23:58PM +1100, David Gibson wrote:
> This makes a number of cleanups to handling of mapping failures during
> memory hotplug on Power:
> 
> For errors creating the linear mapping for the hot-added region:
>   * This is now reported with EFAULT which is more appropriate than the
>     previous EINVAL (the failure is unlikely to be related to the
>     function's parameters)
>   * An error in this path now prints a warning message, rather than just
>     silently failing to add the extra memory.
>   * Previously a failure here could result in the region being partially
>     mapped.  We now clean up any partial mapping before failing.
> 
> For errors creating the vmemmap for the hot-added region:
>    * This is now reported with EFAULT instead of causing a BUG() - this
>      could happen for external reason (e.g. full hash table) so it's better
>      to handle this non-fatally
>    * An error message is also printed, so the failure won't be silent
>    * As above a failure could cause a partially mapped region, we now
>      clean this up.
> 
> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

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