From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A94D86FC3; Thu, 10 Jul 2025 08:44:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752137054; cv=none; b=h4fsQJaPIlFxzKHYCUHqQHUNbNjE8VEMIrDvWcJTCF7Y8TzqajPoEzwWXIDXbWNtXJYW9GmXUsDTC3EBIzShawDCgZUDNjbPSTJlsExkYjfY2eXQR/fW8N/Lql8ujqk70+kaZlZgUh7neabmd7VVlDz7r0GzEo4Eno+1KMq88zE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752137054; c=relaxed/simple; bh=YhSRhuxKLROI2NTRCx6TpQscIMdYxuJr5ktJPi+O3pI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=d1CxnZyj/ThflBtmhXdLq0PfPpqbLh3U7JvfmWJVCz3wYM8LTPwi/0V1U4wvxNHg3xYJstuV1rV/4slYRQud2Q46P9lmnYUBQ7TGcQ+YQilV5g1V+RPnONq+t30HwxayYV7h3BdDYv1pFP/9ekb+Qop7TRytKxTitd/66orFVDQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 A24511EA6; Thu, 10 Jul 2025 01:44:00 -0700 (PDT) Received: from [10.1.196.46] (e134344.arm.com [10.1.196.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2159A3F738; Thu, 10 Jul 2025 01:44:10 -0700 (PDT) Message-ID: Date: Thu, 10 Jul 2025 09:44:09 +0100 Precedence: bulk X-Mailing-List: linux-next@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: linux-next: build warning after merge of the bitmap tree To: Stephen Rothwell , Yury Norov Cc: Linux Kernel Mailing List , Linux Next Mailing List References: <20250710183449.20e255b4@canb.auug.org.au> Content-Language: en-US From: Ben Horgan In-Reply-To: <20250710183449.20e255b4@canb.auug.org.au> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi Stephen, On 7/10/25 09:34, Stephen Rothwell wrote: > Hi all, > > After merging the bitmap tree, today's linux-next build (arm64 defconfig) > produced this warning: > > arch/arm64/kvm/sys_regs.c: In function 'access_mdcr': > arch/arm64/kvm/sys_regs.c:2654:17: warning: ignoring return value of 'u64_replace_bits' declared with attribute 'warn_unused_result' [-Wunused-result] > 2654 | u64_replace_bits(val, hpmn, MDCR_EL2_HPMN); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Introduced by commit > > f66f9c3d09c1 ("bitfield: Ensure the return values of helper functions are checked") > Sorry to have broken your tree. However, this is a valid warning and this misuse of u64_replace_bits() was the motivation for the commit. The fix can be found here https://lore.kernel.org/kvmarm/20250709093808.920284-1-ben.horgan@arm.com/T/#mc9e47859302654d84b4f2b3d9032d2b595d5df49 Thanks, Ben