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Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <20230703063713.GA3012709@ik1-406-35019.vs.sakura.ne.jp> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.151.185] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 0F4FA10000B X-Stat-Signature: u3gwnowyy6mjw7wxoy9agon5a4748n13 X-HE-Tag: 1688383653-640799 X-HE-Meta: U2FsdGVkX191xLRkQE/1tZy0T83j/bAgyc0TLJNDYfXNqlk85pRA4kHG/BUTL4iGMuh853goG0Ta9YiR6uxLlxaJD4/+mCF8X2/xkn759IbN/qOJ/DaSbt8nZl4bjPa83exEV+4ZbPj1/f+v0ujf33GBotSjHN5NpYxVLOW3M46Pr/yJ/OLtw8TNErvGEoZ8J1DeJ+ws4HnqU37z4WOANlS3G7/OzcYc/5k86lmE7XVA+KbVq83u/+x7Mjzzmh9vgyqFNRDTeKPTNUiJTqg3/Nk+86wmzygpLXIPWoO1iEsGoCRHRLpGMy6d91IuDR+qQAk7Tt5F8k3bi+80b8+4kKteqAdQGcTC0yUUYClWo6iNjncpyrhGj1/SHmo3PnyrJpAo5UDBc0xoNglWDXaB5BDK4ynpoBG0I8cd5bCmEDgTcgjteVfayFuEsnM+3p/axDutOiJ+MueZzs7j/41/PpMrguAW0NUcVb9e4eFNbVK8gRPI0vijH3n2ZxR4AFMFel4sXyzBAURYi+pMvfughfc/GM92Ga5pXDtSDY+yhi6q4Oet8KKOmSe3sHPFmjndbaVm1VavH2m+GTr97VvB0OTN4rsQfw9izuW0bwgYuxFq2ZZ8AmzbFD4PeZPFzQLvTZ5nm2mZC3YMc1A0zplHmuR5Rn9AiB8THs8aDMWp/VlB6Ww3hSUwGy09TUee/PzTUDEzPV2AS512761U1+5S0BYKXGDIGE2rE24jdewBbcRIvABDUaTPuzAGspbIlQHmTCda5o5n91Btf3YsFbj4tPXErwdYKAhvhzjmfi9fHnAqtvHLfRH/tKstAiWCg9hcyJBnLi3nUBoWmkNoAY99r7HE3GVgeXvU2hVFZ1xBhvLY3/8s1OERMJz2ipUgJJQh6vIi3zDveOw+OqwGyFWRiABMe/Q5nYkoJCQzuPvmG5RfrK/siYLhOGL+LrlDvL/8Tgqj6UYrjLg01HICHey hSqChGBP yApLjZAzM34iZWaDN9xn14xMvw+tR/Z71viuHu3Y/QTHK5a7KoKOZerX665TyRQRTDKRSHaS3S/mdrG49wGUd6WUtrLEK05dqZVvPUr+E/gs5FMGEYXdvzP5dZFcHtQlTN7lzP8P/60H8gkq+HXNEw75qr8RgMSyp/6X8kwV3EpfMRqETba/pBjeXLqNFAxXW197AWXmBHfeSPW3Rcg/rJfNhbd0vAf82yWWG 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 2023/7/3 14:37, Naoya Horiguchi wrote: > On Sat, Jul 01, 2023 at 03:28:37PM +0800, Miaohe Lin wrote: >> put_ref_page() is not called to drop extra refcnt when comes from madvise >> in the case pfn is valid but pgmap is NULL leading to page refcnt leak. > > Is this test scenario realistic one? I don't think that we can call madvise() for > such a device memory page. If this is the case, this issue can be thought as > potentioal one (so no need to send to stable). This is a theoretical problem. If pagemap can ever be NULL after page refcnt is increased, this would occur. I think it's not needed to send to stable too. > >> >> Fixes: 1e8aaedb182d ("mm,memory_failure: always pin the page in madvise_inject_error") >> Signed-off-by: Miaohe Lin > > Anyway, the patch looks good to me. Thanks you. > > Acked-by: Naoya Horiguchi Thanks for your review and comment.