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dkim=pass header.d=Nvidia.com header.s=selector2 header.b=Q2AJuCns; dmarc=pass (policy=reject) header.from=nvidia.com; spf=none (imf08.hostedemail.com: domain of jgg@nvidia.com has no SPF policy when checking 40.107.93.55) smtp.mailfrom=jgg@nvidia.com X-Stat-Signature: rqrffjuwtneb868hahaejtzq84a5gbbk X-Rspamd-Server: rspam08 X-HE-Tag: 1643893300-521734 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: On Thu, Feb 03, 2022 at 12:38:33AM -0800, John Hubbard wrote: > On 2/2/22 22:27, Lukas Bulwahn wrote: > > Dear John, > > > > Your change "mm/gup: clean up follow_pfn_pte() slightly" (see Link), > > visible in linux-next as commit 05fef840b5c6 ("mm/gup: clean up > > follow_pfn_pte() slightly"), is somehow weird. > > Well. That sounds like something to be avoided. :) > > > > > In the new branch if (pages), you set page = ERR_PTR(-EFAULT) and goto > > out. However, at the label out, the value of page is not used, but the > > return uses the variables i and ret. > > Yes, I think that the complaint is accurate. The intent of this code is > to return either number of pages so far (i) or ret (which should be zero > in this case), because we are just stopping early, rather than calling > this an actual error. IIRC GUP shouldn't return 0, it should return an error code, not zero. Jason