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Message-ID: <10f2de59-5ef3-9bc0-b359-e0e8474ab92b@oracle.com>
Date: Fri, 16 Feb 2024 14:03:49 -0800
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Subject: Re: [PATCH v2 1/6] mm/migrate: introduce migrate_pfn_to_folio()
Content-Language: en-US
To: Matthew Wilcox <willy@infradead.org>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        akpm@linux-foundation.org, apopple@nvidia.com
References: <20240216211320.222431-1-sidhartha.kumar@oracle.com>
 <Zc_YiSDsmdv-2Rcm@casper.infradead.org>
From: Sidhartha Kumar <sidhartha.kumar@oracle.com>
In-Reply-To: <Zc_YiSDsmdv-2Rcm@casper.infradead.org>
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On 2/16/24 1:50 PM, Matthew Wilcox wrote:
> On Fri, Feb 16, 2024 at 01:13:15PM -0800, Sidhartha Kumar wrote:
>> +static inline struct folio *migrate_pfn_to_folio(unsigned long mpfn)
>> +{
>> +	return page_folio(migrate_pfn_to_page(mpfn));
> 
> umm, no.
> 
> 	struct page *page = migrate_pfn_to_page(mpfn);
> 	if (page)
> 		return page_folio(page);
> 	return NULL;

Thanks, I overlooked checking for NULL before converting the page to a folio. 
I'll make this change for v3.