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Date:   Fri, 7 Jul 2023 09:42:17 -0400
From:   Peter Xu <peterx@redhat.com>
To:     Axel Rasmussen <axelrasmussen@google.com>
Cc:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
        Brian Geffon <bgeffon@google.com>,
        Christian Brauner <brauner@kernel.org>,
        David Hildenbrand <david@redhat.com>,
        Gaosheng Cui <cuigaosheng1@huawei.com>,
        Huang Ying <ying.huang@intel.com>,
        Hugh Dickins <hughd@google.com>,
        James Houghton <jthoughton@google.com>,
        "Jan Alexander Steffens (heftig)" <heftig@archlinux.org>,
        Jiaqi Yan <jiaqiyan@google.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Kefeng Wang <wangkefeng.wang@huawei.com>,
        "Liam R. Howlett" <Liam.Howlett@oracle.com>,
        Miaohe Lin <linmiaohe@huawei.com>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        "Mike Rapoport (IBM)" <rppt@kernel.org>,
        Muchun Song <muchun.song@linux.dev>,
        Nadav Amit <namit@vmware.com>,
        Naoya Horiguchi <naoya.horiguchi@nec.com>,
        Ryan Roberts <ryan.roberts@arm.com>,
        Shuah Khan <shuah@kernel.org>,
        Suleiman Souhlal <suleiman@google.com>,
        Suren Baghdasaryan <surenb@google.com>,
        "T.J. Alumbaugh" <talumbau@google.com>,
        Yu Zhao <yuzhao@google.com>,
        ZhangPeng <zhangpeng362@huawei.com>, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-mm@kvack.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH v3 7/8] selftests/mm: refactor uffd_poll_thread to allow
 custom fault handlers
Message-ID: <ZKgWOYuIdqa25Qcs@x1n>
References: <20230706225037.1164380-1-axelrasmussen@google.com>
 <20230706225037.1164380-8-axelrasmussen@google.com>
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On Thu, Jul 06, 2023 at 03:50:35PM -0700, Axel Rasmussen wrote:
> @@ -247,9 +245,13 @@ static int userfaultfd_stress(void)
>  {
>  	void *area;
>  	unsigned long nr;
> -	struct uffd_args args[nr_cpus];
> +	struct uffd_args *args;
>  	uint64_t mem_size = nr_pages * page_size;
>  
> +	args = calloc(nr_cpus, sizeof(struct uffd_args));
> +	if (!args)
> +		err("allocating args array failed");

This is trivial, but I think I requested a "free" (or keep it allocate on
stack) in previous version but it didn't get a response on why we cannot
and it kept going..  could you help explain?

-- 
Peter Xu