netdev - Re: [PATCH net-next 2/5] sfc: Use kmap_local_page() instead of kmap

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Message-ID: <164778f1-f2a6-1e82-8924-a4d7ba073e23@intel.com>
Date:   Fri, 18 Nov 2022 09:47:52 -0800
From:   Anirudh Venkataramanan <anirudh.venkataramanan@...el.com>
To:     "Fabio M. De Francesco" <fmdefrancesco@...il.com>,
        <netdev@...r.kernel.org>
CC:     Ira Weiny <ira.weiny@...el.com>,
        Edward Cree <ecree.xilinx@...il.com>,
        Martin Habets <habetsm.xilinx@...il.com>
Subject: Re: [PATCH net-next 2/5] sfc: Use kmap_local_page() instead of
 kmap_atomic()

On 11/18/2022 12:23 AM, Fabio M. De Francesco wrote:
> On giovedì 17 novembre 2022 23:25:54 CET Anirudh Venkataramanan wrote:
>> kmap_atomic() is being deprecated in favor of kmap_local_page().
>> Replace kmap_atomic() and kunmap_atomic() with kmap_local_page()
>> and kunmap_local() respectively.
>>
>> Note that kmap_atomic() disables preemption and page-fault processing, but
>> kmap_local_page() doesn't. Converting the former to the latter is safe only
>> if there isn't an implicit dependency on preemption and page-fault handling
>> being disabled, which does appear to be the case here.
> 
> NIT: It is always possible to disable explicitly along with the conversion.

Fair enough. I suppose "convert" is broader than "replace". How about this:

"Replacing the former with the latter is safe only if there isn't an 
implicit dependency on preemption and page-fault handling being 
disabled, which does appear to be the case here."

Ani