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Message-ID: <1c2117f1-2d22-4d08-bd9f-8c821d4a1757@intel.com>
Date:   Fri, 13 Oct 2023 19:18:37 +0200
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Subject: Re: [PATCH v2] ACPI: NFIT: Fix local use of devm_*()
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To:     Dan Williams <dan.j.williams@intel.com>, <nvdimm@lists.linux.dev>,
        <linux-acpi@vger.kernel.org>
CC:     <rafael@kernel.org>, <vishal.l.verma@intel.com>, <lenb@kernel.org>,
        <dave.jiang@intel.com>, <ira.weiny@intel.com>,
        <linux-kernel@vger.kernel.org>,
        Andy Shevchenko <andy.shevchenko@gmail.com>
References: <20231013085722.3031537-1-michal.wilczynski@intel.com>
 <6529727e18964_f879294ea@dwillia2-mobl3.amr.corp.intel.com.notmuch>
 <f7441bb4-c2c9-4eee-9fed-ad8b28de4788@intel.com>
 <652978deafdf8_f8792944c@dwillia2-mobl3.amr.corp.intel.com.notmuch>
From:   "Wilczynski, Michal" <michal.wilczynski@intel.com>
In-Reply-To: <652978deafdf8_f8792944c@dwillia2-mobl3.amr.corp.intel.com.notmuch>
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On 10/13/2023 7:05 PM, Dan Williams wrote:
> Wilczynski, Michal wrote:
>> On 10/13/2023 6:38 PM, Dan Williams wrote:
>>> Michal Wilczynski wrote:
>>>> devm_*() family of functions purpose is managing memory attached to a
>>>> device. So in general it should only be used for allocations that should
>>>> last for the whole lifecycle of the device. 
>>> No, this assertion is not accurate, if it were strictly true then
>>> devm_kfree() should be deleted. This patch is only a cleanup to switch
>>> the automatic cleanup pattern from devm to the new cleanup.h helpers.
>> The memory in question is only used locally in a function, so there is no reason
>> to use devm_*() family of functions. I think devm_kfree() is more for special
>> cases where the memory is meant to be used for the whole lifecycle of device,
>> but some special case occurs and it's not and it needs to be freed.
>>
>> This is an incorrect API usage. Would you propose to change all memory
>> allocations currently being done to devm_*() family simply because devm_kfree()
>> exists ?
> Michal, please work with someone else to get these cleanups upstream, I
> am done with this thread.

I'm really sorry if I offended you, I didn't mean to.

Michał