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Date: Fri, 23 Jan 2026 09:20:03 +0100
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Subject: Re: [PATCH v3 5/9] selftests/mm: check that FORCE_READ() succeeded
To: Usama Anjum <usama.anjum@foss.arm.com>, linux-mm@kvack.org,
 linux-kselftest@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>,
 David Hildenbrand <david@kernel.org>, Dev Jain <dev.jain@arm.com>,
 Lorenzo Stoakes <lorenzo.stoakes@oracle.com>, Mark Brown
 <broonie@kernel.org>, Ryan Roberts <ryan.roberts@arm.com>,
 Shuah Khan <shuah@kernel.org>
References: <20260122170224.4056513-1-kevin.brodsky@arm.com>
 <20260122170224.4056513-6-kevin.brodsky@arm.com>
 <ab021f50-60c9-4d5c-99a0-255ead6e2288@foss.arm.com>
From: Kevin Brodsky <kevin.brodsky@arm.com>
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On 22/01/2026 18:36, Usama Anjum wrote:
>> +static bool populate_page_checked(char *addr)
>> +{
>> +    bool ret;
>> +
>> +    FORCE_READ(*addr);
>> +    ret = pagemap_is_populated(pagemap_fd, addr);
> Very useful. Maybe extending FORCE_READ can help the entire suite?

I considered it but one needs to have a pagemap fd around, so we'd have
to open it for every test that uses the helper. Maybe such check is not
so essential either (see David's reply).

- Kevin