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Subject: Re: [Jfs-discussion] [PATCH] jfs: Add missing NULL pointer check in
 __get_metapage
To:     Juerg Haefliger <juerg.haefliger@canonical.com>,
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From:   Dave Kleikamp <dave.kleikamp@oracle.com>
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Date:   Thu, 2 Nov 2017 09:44:03 -0500
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On 11/02/2017 08:43 AM, Juerg Haefliger wrote:

>>>> Furthermore, it looks like all the callers of __get_metapage() check for
>>>> a null return, so I'm not sure we need to handle the error at this
>>>> point. I might have to look a bit harder at that, since there are many
>>>> callers.
>>>
>>> I don't understand this either :-) Yes, the callers do check for a null
>>> pointer but things blow up (in __get_metapage) before that check without
>>> the above fix.
>>
>> Yeah, the fix to __get_metapage() is necessary. I'm not convinced the
>> first part of the patch, to alloc_metapage(), is necessary.
> 
> It's not. I just thought it'd be nice to get some sort of notification
> in the log when the alloc fails. But if the callers log it then that's fine.

Okay. I'll push just the __get_metapage part of your patch.

Thanks,
Shaggy

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