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Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <20230719234851.GA1583723@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: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected X-Rspamd-Queue-Id: 3F1C640019 X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: uj69t5k3r5qt5hxf5gpo9eik8diexkw4 X-HE-Tag: 1689842647-128744 X-HE-Meta: U2FsdGVkX18nxNLVznEgU0c85tIiodmuwWhZseBnwEtpZjNsn0NGLe0MpdZ32QlL4Ht5Xh4zoZ3ANLkLyZA0EDNVaVM23O4hNdPzlAD4roQtAMXMYY4lTfVb3+b0DMx9AFBxgqSS7Bf175cKVBwiyJW2NMhBxMUeOieWQM5MpggY4UQD75VRGW1VnVmKOj4U3qmDNZMTC0b44VFZv52FbQnCZcS/6WXx7duVN/27aeSb5cHyRGQorRQmV6shYpw+5NIlaCqs+TN736S/C8jOeooFlM3jNBCtcNRxz2itP4DjDv+byUCFSHyaOHK5CuR5HGOHSnsG/9MTHBcLy2SclBiQAqROCCoTgqnFblNXePp5O6RtrngpwSpwDoTcd3o1f8K3/GWf3qQ/bo/S+6pF7aKxT+cWJ4kgL5T2vUQLHjicnU912raTV/PNes8uoaNxl+lnzAwFT+SFeDROjArNuZLz8md1dJmDDk6HPSEUhMf25LeQv2lpfHO6gVFPTgWbd460rt/34GzM37T5OMWroC1hJJDMBEegipQVnb048A+LLUbWTCWZFN+exJXrp21HRfawHWFXQNz+7BI//tyCSyw4Y7YoH8bBaJJkjiFKIWKMB+JkKq27ndRckjz81pUnZDc/7ZUqDNHo+mCN7ix/WDjmAeAJ1eYBjoPCPprMXKfJL4yefDfJnjI3o7zEG14WYDxqjLYpf19+05KAJoDP5bZ1WMIhhIucGvMMzeeDDSr6u7m2dpZML/s6FxNWmzqABX6s96zE2CcJEO7LZQp45/amSnc/M9RpjUPHvFWckjPSqovEAAcNSN8I+e6lFrvJR+c5CKUG71kZRhrGXaGXAecVxIKIuYMmriqNGk1ggn6FMuhuSGfsLXsbcU+/jebGLcDOlcrbeGoaqUhGoZFL4/lPNMVCXfg2M+/MDkwCH3FCZPeF31Q1Dj6TZy3U94pfUxon2rFXVpAokIzpxrs bGZ9haPh mGd1fZ0LqRZNcmM8rVlA3K283OC0Ni4E6asFYIkHTqe55nWQgHGFEWk40xyoMqFIuIn+jbw3IszmK6qt7pAbXxrs7VyQI+ez8cNgqnDcSX916FgoSHDMo9EeZ4VrfyogW/aqUFCs9eUOvff2avVAQu4iU6cC1V96Sd+f1gq8TVkVIP5ykWjvbAsN84Hn4bB3N69qV 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 2023/7/20 7:48, Naoya Horiguchi wrote: > On Sat, Jul 15, 2023 at 11:17:27AM +0800, Miaohe Lin wrote: >> If unpoison_memory() fails to clear page hwpoisoned flag, return value >> ret is expected to be -EBUSY. But when get_hwpoison_page() returns 1 >> and fails to clear page hwpoisoned flag due to races, return value will >> be unexpected 1 leading to users being confused. > > Thank you for fixing this. > >> >> Fixes: bf181c582588 ("mm/hwpoison: fix unpoison_memory()") >> Signed-off-by: Miaohe Lin >> --- >> mm/memory-failure.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/mm/memory-failure.c b/mm/memory-failure.c >> index 9ab97016877e..ac074f82f5b3 100644 >> --- a/mm/memory-failure.c >> +++ b/mm/memory-failure.c >> @@ -2546,11 +2546,11 @@ int unpoison_memory(unsigned long pfn) >> unpoison_pr_info("Unpoison: failed to grab page %#lx\n", >> pfn, &unpoison_rs); >> } else { >> + ret = -EBUSY; > > It seems be a code smell to me that the variable "ret" is used not only to > save the return value of unpoison_memory(), but also to save the return > value from get_hwpoison_page(). So I think that it might be better to use > another auto-variable solely to save the return value of get_hwpoison_page. > Then ret has the initial value -EBUSY at this point and no need to > reinitialize it. > This should be a nice improvement. Will do it in v2. Thanks Naoya.