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Wysocki" , Danilo Krummrich , "Andrew Morton" References: <20260428085219.1316047-1-songmuchun@bytedance.com> <20260428085219.1316047-4-songmuchun@bytedance.com> From: Miaohe Lin Message-ID: Date: Tue, 28 Apr 2026 19:37:21 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <20260428085219.1316047-4-songmuchun@bytedance.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.173.124.160] X-ClientProxiedBy: kwepems500002.china.huawei.com (7.221.188.17) To kwepemq500010.china.huawei.com (7.202.194.235) X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 055A2140005 X-Rspam-User: X-Stat-Signature: gc9xgs7etmbxcgsyyp75tozk4e8qysz4 X-HE-Tag: 1777376247-947370 X-HE-Meta: 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 e15hV818 7LnvmNKNXxNGiMM0Q2QkXSn5U5eiQLyJLNSlwvlqhBcQpj2SdFY2m4HuZweev6yml6h6bYqLskcup3FL/u7oOyonFaAPqLdkU/heo61fzRRk6Wlr5lvAp7lxJS0v2pzh/hHJVJC+NwhPLS63FbiPISf9gNWX0qEMtRiM7jEiz24Hch9LoM3zCkcIukxlDrOEw8I+ww9cKAzYPbm3/atNEJGaybFMffWMxdknY1hAZOo97sGlbwxVTLU7I79MIaXQpRsBso8WtFIHCxNL0APAhhoacRW2Poj7AZS6tfjbfU15az0VqPhr3YTTkzz8SUMhExlx1FMfV52B3GeqqG89X0AHZOvqHun6ILtfDjEPMvEuf9u4= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2026/4/28 16:52, Muchun Song wrote: > memblk_nr_poison_inc() and memblk_nr_poison_sub() call > find_memory_block_by_id(), which requires device_hotplug_lock to > serialize the xarray lookup against memory block removal. > > Take device_hotplug_lock around the lookup and nr_hwpoison update so > the memory block cannot disappear between xa_load() and get_device(). > > Fixes: 5033091de814 ("mm/hwpoison: introduce per-memory_block hwpoison counter") > Cc: stable@vger.kernel.org > Signed-off-by: Muchun Song Thanks for update. > --- > drivers/base/memory.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/base/memory.c b/drivers/base/memory.c > index 6981b55d582a..f76aee29e9a5 100644 > --- a/drivers/base/memory.c > +++ b/drivers/base/memory.c > @@ -1228,23 +1228,29 @@ int walk_dynamic_memory_groups(int nid, walk_memory_groups_func_t func, > void memblk_nr_poison_inc(unsigned long pfn) > { > const unsigned long block_id = pfn_to_block_id(pfn); > - struct memory_block *mem = find_memory_block_by_id(block_id); > + struct memory_block *mem; > > + lock_device_hotplug(); memblk_nr_poison_inc() and memblk_nr_poison_sub() are both called from memory_failure() context. I'm afraid if memory_failure() is triggered while lock_device_hotplug is held, it will lead to deadlock. Or am I miss something? Thanks. .