From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 003.mia.mailroute.net (003.mia.mailroute.net [199.89.3.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9A5F431B822; Wed, 19 Nov 2025 23:09:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=199.89.3.6 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763593760; cv=none; b=jcAnARb/T4BB7WaNtRTSEThJKycu1mKpOFBHCwz+5ghhzkTRz7/+7tmD5zef054EB9QuRyPzsqjXkv/+aUogt+lwAT8xZRiujjUup9lLDjlhDqrTtOAAB8lhfTDe4Dxyx5iM+BD/cZOMk/wGq+PFwDf3vhnRd58aAp/gCCr+yWA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763593760; c=relaxed/simple; bh=48U3P296JngEYZDwTM1DjxIEBD3kVyCsdLXj322BcB8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=PRPWoBQWzEBi10a5h7Qp7iWbHh0CATYvZnlroLHy0kwKZI7T89Mhm48dsCoGIZpTnZslOk60P+Y6ynqkQNkD4f0WOTm62Bmzc0c1exJ/V7Zs9OWqLn5N37IGvwO9j6I32jV1GowY5/tQsy89txkKDENhEPQwei7wvRKxFTUhqXA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org; spf=pass smtp.mailfrom=acm.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b=3d1LRML4; arc=none smtp.client-ip=199.89.3.6 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=acm.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b="3d1LRML4" Received: from localhost (localhost [127.0.0.1]) by 003.mia.mailroute.net (Postfix) with ESMTP id 4dBccQ2mDfzlvBxP; Wed, 19 Nov 2025 23:09:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=acm.org; h= content-transfer-encoding:content-type:content-type:in-reply-to :from:from:content-language:references:subject:subject :user-agent:mime-version:date:date:message-id:received:received; s=mr01; t=1763593749; x=1766185750; bh=koVPuGOvUsw69MMbphSKyma6 aYRpMsCzH/YNtIFlZx8=; b=3d1LRML4gWV4OZjTJS9ug+nYzEi/2AnhGMQ5bSV2 vHHQFDX4ssxLpNNkNEi/C13GRfpY5NAnRovfbFq9QCwlo2Hc5VUWWlHtBlDodHdD Tf6x0DpVM2wrzkRfXBPKLHZWHjZ87Xs1M9Z5YIlCKGAVb1QKzmNfD8SIBFPmt9cY WRHnwmUxQvCVmgimTITgmaphh2S31omjj6e85iWhTrb/fPXAb5YxVnd5HNbAnb8Q mVXN4PyJg3dXVZstt5YtBtRIRC9PkR8idP1LL0K4FWVZHxh7PK1xnbDClw5o0OXh 4cRlVVX5lGU+XFuXAoNJqKldgz+IGmAaDIzLe2qGFCro4w== X-Virus-Scanned: by MailRoute Received: from 003.mia.mailroute.net ([127.0.0.1]) by localhost (003.mia [127.0.0.1]) (mroute_mailscanner, port 10029) with LMTP id oATAiD0aMpiL; Wed, 19 Nov 2025 23:09:09 +0000 (UTC) Received: from [100.119.48.131] (unknown [104.135.180.219]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bvanassche@acm.org) by 003.mia.mailroute.net (Postfix) with ESMTPSA id 4dBccJ02BpzlvDRD; Wed, 19 Nov 2025 23:09:03 +0000 (UTC) Message-ID: <2a8c62e1-6e29-4ac6-b661-7b5ec1763288@acm.org> Date: Wed, 19 Nov 2025 15:09:02 -0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 26/44] drivers/scsi: use min() instead of min_t() To: david.laight.linux@gmail.com, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org Cc: "James E.J. Bottomley" , "Martin K. Petersen" References: <20251119224140.8616-1-david.laight.linux@gmail.com> <20251119224140.8616-27-david.laight.linux@gmail.com> Content-Language: en-US From: Bart Van Assche In-Reply-To: <20251119224140.8616-27-david.laight.linux@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 11/19/25 2:41 PM, david.laight.linux@gmail.com wrote: > From: David Laight > > min_t(unsigned int, a, b) casts an 'unsigned long' to 'unsigned int'. > Use min(a, b) instead as it promotes any 'unsigned int' to 'unsigned long' > and so cannot discard significant bits. > > In this case the 'unsigned long' value is small enough that the result > is ok. > > Detected by an extra check added to min_t(). > > Signed-off-by: David Laight > --- > drivers/scsi/hosts.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c > index 17173239301e..b15896560cf6 100644 > --- a/drivers/scsi/hosts.c > +++ b/drivers/scsi/hosts.c > @@ -247,7 +247,7 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev, > shost->dma_dev = dma_dev; > > if (dma_dev->dma_mask) { > - shost->max_sectors = min_t(unsigned int, shost->max_sectors, > + shost->max_sectors = min(shost->max_sectors, > dma_max_mapping_size(dma_dev) >> SECTOR_SHIFT); > } So instead of the type cast performed by min_t() potentially discarding bits, the assignment potentially discards bits. I'm not sure this is an improvement. Thanks, Bart.