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s=arc-20220608; d=hostedemail.com; t=1655272330; a=rsa-sha256; cv=none; b=qANHBrIwfNERN5+hjPCZ407OMIdhych35sON1bw4XMb2q/c2BWbwZPhwd9GGnrspKJNcQI 4pBHNvOcQ+oxHTaNtX+RYlIVH0sFTZ28DYaxxedU3qNJOvimSqJMc6afi6Kf5gHPencBKw Z7syxPO+as+RQdD0MbFmceZSIJSqgyI= X-Rspamd-Queue-Id: C3DF814008B X-Rspam-User: X-Stat-Signature: qs4jfbhs6mg1b4itnibbqoo4gfyi99hh Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=tTf8FArW; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=eA+EsViO; dmarc=pass (policy=none) header.from=suse.de; spf=pass (imf09.hostedemail.com: domain of osalvador@suse.de designates 195.135.220.29 as permitted sender) smtp.mailfrom=osalvador@suse.de X-Rspamd-Server: rspam04 X-HE-Tag: 1655272329-756201 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000004, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Jun 15, 2022 at 01:18:23PM +0800, zhenwei pi wrote: > Hi, > > Because memory_failure() may be called by hardware error randomly, > hw_memory_failure should be protected by mf_mutex to avoid this case: > int unpoison_memory(unsigned long pfn) > { > ... > if (hw_memory_failure) { > } > ... --> memory_failure() happens, and mark hw_memory_failure as true > mutex_lock(&mf_mutex); Yeah, I am aware of that. But once memory_failure() sets hw_memory_failure to true, it does not really matter whether unpoison_memory() checks that while holding or not the lock, does it? Note that it does not really matter in the end, but I am just curious whether there is any strong impediment to that. -- Oscar Salvador SUSE Labs