From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 52717CD4851 for ; Tue, 12 May 2026 12:21:40 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 904006B0088; Tue, 12 May 2026 08:21:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8B4FC6B008A; Tue, 12 May 2026 08:21:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7CB8D6B008C; Tue, 12 May 2026 08:21:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 6D2D26B0088 for ; Tue, 12 May 2026 08:21:39 -0400 (EDT) Received: from smtpin15.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 0EA2F4042E for ; Tue, 12 May 2026 12:21:39 +0000 (UTC) X-FDA: 84758678718.15.8CFDA5D Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf29.hostedemail.com (Postfix) with ESMTP id 6257B12000B for ; Tue, 12 May 2026 12:21:37 +0000 (UTC) Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=j83PBPm9; spf=pass (imf29.hostedemail.com: domain of rppt@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1778588497; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=/rOFx8fP/g0553IE8eeAsVhGXObHgM23EMozFGNOA+A=; b=4sWWb7uD055kurTnPw8bpGReUma84EiPIeAJwOR/G3oXSl8wNRWAsYrmHRN5fla6UTcufy xjU+tfqxWF4MLeVprUx7lGE8dWr0rGOlj/Snq/HPLyDaKwVmWdAAA4L0SskAwSUQyKnbaX nTvsK/Ib6zYhJwKdVNocQfJdPWTnQAM= ARC-Authentication-Results: i=1; imf29.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=j83PBPm9; spf=pass (imf29.hostedemail.com: domain of rppt@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1778588497; a=rsa-sha256; cv=none; b=ucIcIpu/ax/sYZ4cL8IMbSRLk0LDqAZTuqvVKE2TxV1nJHbPxgO6IFErz7K3JX31H+wgkg oul8D/AKeBEkGBIzlUWNqmFdA1wFjysHnZjpItA10StIPHu7kZoiGQcx0Tz7yO/cKJ/slq Dt3Mm8s7ccnEZWDuA6fkVf4/A778SKU= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id BEA29600CB; Tue, 12 May 2026 12:21:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 65147C2BCB0; Tue, 12 May 2026 12:21:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778588496; bh=wqAIUXGNRFLlciEzYLfd74vbbJTuTmippmPLs7dX3ss=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=j83PBPm90V70Z5DzvXF/3ALqo6TXArDPPwEh49VBE2prM9PIC8+QiZm8wPP1vX0ES fEqsbz26nHNAhiXOyR/MEJHOLhUDrAYgycH4Ep0mcOx3E9YfLFeMqUYxC2FNw7ed7T /TLDLKuSf9FZPO7ncyuDSSmzbXMdJlN3DtvRM7ZbFxkvWOkMS4NEiczktj0VWg9WZf LG+kjWyYJhnmfZ2EXeJ8ynXUMi+f/tPRQ3poYQ0ez2jSAZj24dxEtXnGE5yP6ChUZd yUxcB/Z91qGqxb3a46U6SDuzlEU5e7yTVJmX5lozqtxmRqXmpvtTx3ERcZH5Ap4a6d HfZkFvN4Hg3EQ== Date: Tue, 12 May 2026 15:21:28 +0300 From: Mike Rapoport To: Hongfu Li Cc: jgg@ziepe.ca, leon@kernel.org, akpm@linux-foundation.org, david@kernel.org, ljs@kernel.org, vbabka@kernel.org, surenb@google.com, mhocko@suse.com, shuah@kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] selftests/mm: Fix mmap() return value check in run_migration_benchmark Message-ID: References: <20260512101305.139509-1-lihongfu@kylinos.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260512101305.139509-1-lihongfu@kylinos.cn> X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 6257B12000B X-Stat-Signature: 3jzdtsapz7k41ktugzbynsizeg9tezez X-HE-Tag: 1778588497-687247 X-HE-Meta: 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 YZzoBMqa k28cDoAwchpyx0lHImAkCYhC43FI0lKg38QUzgXzml907kHWIVreoZubSe8hyUQIYCc2KKSzHNMCbjbcw+3TFQy3+ohckWZlzUs+EQBY27IYzXKTpiCU72GmDOnkbyK+ijzinDgGnBZcEZ316tcrIWhk4T1qvLNatfdzZYBU5AjMQviCWGB4hOA4AydTN3IiN6Erq03PzTxc9S2Nzq4cu+BL5WGPZA2wL13im+j7sIGHZiKkD+0/44hQeasLWRVKeUgDlcV7YRupSGI9Lk3o4aPd1QtJP9OIXLcVNriqO2PlBKUY/a+cE6Ci/JQa+DM9xXiFuMulee8tXnK0= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, May 12, 2026 at 06:13:05PM +0800, Hongfu Li wrote: > mmap() returns MAP_FAILED on error, not NULL. The current check uses > !buffer->ptr, which evaluates to false when mmap() fails (since > MAP_FAILED is (void *)-1, not 0), so the error path is never taken. > > Signed-off-by: Hongfu Li Acked-by: Mike Rapoport (Microsoft) > --- > tools/testing/selftests/mm/hmm-tests.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/mm/hmm-tests.c b/tools/testing/selftests/mm/hmm-tests.c > index 788689497e92..d72adba5c74e 100644 > --- a/tools/testing/selftests/mm/hmm-tests.c > +++ b/tools/testing/selftests/mm/hmm-tests.c > @@ -2688,7 +2688,7 @@ static inline int run_migration_benchmark(int fd, int use_thp, size_t buffer_siz > buffer->ptr = mmap(NULL, buffer_size, PROT_READ | PROT_WRITE, > MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); > > - if (!buffer->ptr) > + if (buffer->ptr == MAP_FAILED) > return -1; > > /* Apply THP hint if requested */ > -- > 2.25.1 > -- Sincerely yours, Mike.