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Mon, 22 Jan 2024 17:19:28 +0000 (UTC) X-FDA: 81707608416.20.C099CF2 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf12.hostedemail.com (Postfix) with ESMTP id 0034F4002C for ; Mon, 22 Jan 2024 17:19:25 +0000 (UTC) Authentication-Results: imf12.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf12.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1705943966; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=tGwlPw30/J76U61YiwWJyqAQpT1/rdPz0XhyZp/H8mY=; b=xowfhEspxDr/uoxAkFg+p9+eu/oiQ/jEw14HGY60VBlPXdOBCTWpmV7ukJdoB+GwUy15KO wehn8VdzMDl5zOvFvx96dogDzari53HPRgpPBAC7zhCRHPDuSiuHmb/6yosppHipOfxduZ ttwcR89sfb1/F0wNXs1cKMNVVG1MoGg= ARC-Authentication-Results: i=1; imf12.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf12.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1705943966; a=rsa-sha256; cv=none; b=l/ggKTkLPaVNwJvTB1UnbQc4bhYO91eWlnFJYyBIMh+rEAQFEuY82s8H2HjVCKhuE192et x8WaLFTfj0lM/S1op/FyS8usMicbTu93EVYdT+Obt9O4Mz0nj56aGAc6rbXSC5mrM8wBW/ xKO2CmvVpESHpDqNnLVZhRZdWmKKNZE= Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 290CD1FB; Mon, 22 Jan 2024 09:20:11 -0800 (PST) Received: from [10.1.33.151] (XHFQ2J9959.cambridge.arm.com [10.1.33.151]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DB2F93F5A1; Mon, 22 Jan 2024 09:19:23 -0800 (PST) Message-ID: <3069ea17-d470-4f02-a411-99638485c430@arm.com> Date: Mon, 22 Jan 2024 17:19:22 +0000 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 08/10] mm: Convert to should_zap_page() to should_zap_folio() Content-Language: en-GB To: Kefeng Wang , kernel test robot , "Matthew Wilcox (Oracle)" , Andrew Morton Cc: llvm@lists.linux.dev, oe-kbuild-all@lists.linux.dev, Linux Memory Management List , david@redhat.com, linux-s390@vger.kernel.org References: <20240111152429.3374566-9-willy@infradead.org> <202401121250.A221BL2D-lkp@intel.com> <962a7993-fce9-4de8-85cd-25e290f25736@huawei.com> From: Ryan Roberts In-Reply-To: <962a7993-fce9-4de8-85cd-25e290f25736@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 0034F4002C X-Stat-Signature: copj6gryoqbjeg1rfznp4b3j5mkqyqhz X-HE-Tag: 1705943965-384050 X-HE-Meta: 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 Wjq+kh3j 5JuLAJFToWpw9RejFO1y0XwPxkPy5oGtzSLujyyUb9LHGhwyNfac5wVgkOlSWBF31pxBfpCqOMo1gy+78X42FnAIiDG3W6ntzdRcyu2AdKljzb8q1Ng8kof1pRix50bhNes/b0TR7wjP+ydWMUMZtcaf48ba2ANsK5WMXwWN+3QgvGddoPjNtIi8YuWQrUn36lvtKztS8c8VVmcdnS2TJDAKzGwkgG2jiJoOcrhxHO2alvVY/n09KgE42FD9KWq97YHEQ+G0mOzKrf3VKYyUPYDMls2x70oMRCcuCiwDxfHFWFrQ12hLPEzCjKWvXcLDhjUY/Ye0x4tZQuMGl27P6NJh5PRSjswpnpvgpFPuGu1HmdC4Khj/3+TCC/pygrQOfAftQZFXKEWfPyeiDsgkqK8yyyQgQ2pc7W7+9 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 12/01/2024 10:14, Kefeng Wang wrote: > > > On 2024/1/12 13:03, kernel test robot wrote: >> Hi Matthew, >> >> kernel test robot noticed the following build warnings: >> >> [auto build test WARNING on akpm-mm/mm-everything] >> >> url:    >> https://github.com/intel-lab-lkp/linux/commits/Matthew-Wilcox-Oracle/mm-Add-pfn_swap_entry_folio/20240111-232757 >> base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything >> patch link:    >> https://lore.kernel.org/r/20240111152429.3374566-9-willy%40infradead.org >> patch subject: [PATCH v3 08/10] mm: Convert to should_zap_page() to >> should_zap_folio() >> config: arm-milbeaut_m10v_defconfig >> (https://download.01.org/0day-ci/archive/20240112/202401121250.A221BL2D-lkp@intel.com/config) >> compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git >> ae42196bc493ffe877a7e3dff8be32035dea4d07) >> reproduce (this is a W=1 build): >> (https://download.01.org/0day-ci/archive/20240112/202401121250.A221BL2D-lkp@intel.com/reproduce) >> >> If you fix the issue in a separate patch/commit (i.e. not just a new version of >> the same patch/commit), kindly add following tags >> | Reported-by: kernel test robot >> | Closes: >> https://lore.kernel.org/oe-kbuild-all/202401121250.A221BL2D-lkp@intel.com/ >> >> All warnings (new ones prefixed by >>): >> >>>> mm/memory.c:1451:8: warning: variable 'folio' is used uninitialized whenever >>>> 'if' condition is false [-Wsometimes-uninitialized] >>                             if (page) >>                                 ^~~~ >>     mm/memory.c:1454:44: note: uninitialized use occurs here >>                             if (unlikely(!should_zap_folio(details, folio))) >>                                                                     ^~~~~ >>     include/linux/compiler.h:77:42: note: expanded from macro 'unlikely' >>     # define unlikely(x)    __builtin_expect(!!(x), 0) >>                                                 ^ >>     mm/memory.c:1451:4: note: remove the 'if' if its condition is always true >>                             if (page) >>                             ^~~~~~~~~ >>     mm/memory.c:1438:22: note: initialize the variable 'folio' to silence this >> warning >>                     struct folio *folio; >>                                        ^ >>                                         = NULL > > Hi Andrew, please help to squash following change, thanks. I just independently found this issue during coincidental review of the code. It's still a problem in mm-unstable, so wondered if you missed the request, Andrew? > > diff --git a/mm/memory.c b/mm/memory.c > index 998237b5600f..5e88d5379127 100644 > --- a/mm/memory.c > +++ b/mm/memory.c > @@ -1435,7 +1435,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb, >         arch_enter_lazy_mmu_mode(); >         do { >                 pte_t ptent = ptep_get(pte); > -               struct folio *folio; > +               struct folio *folio = NULL; >                 struct page *page; > >                 if (pte_none(ptent)) > > >