From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [BUG REPORT] [mm-hotplug, aio] aio ring_pages can't be offlined Date: Fri, 30 Nov 2012 00:00:43 -0800 Message-ID: <20121130000043.cf356676.akpm@linux-foundation.org> References: <1354172098-5691-1-git-send-email-linfeng@cn.fujitsu.com> <20121129153930.477e9709.akpm@linux-foundation.org> <50B82B0D.8010206@cn.fujitsu.com> <20121129215749.acfd872a.akpm@linux-foundation.org> <50B85C8C.2030702@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Lin Feng , viro@zeniv.linux.org.uk, bcrl@kvack.org, mhocko@suse.cz, hughd@google.com, cl@linux.com, mgorman@suse.de, minchan@kernel.org, isimatu.yasuaki@jp.fujitsu.com, laijs@cn.fujitsu.com, wency@cn.fujitsu.com, tangchen@cn.fujitsu.com, linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org To: Kamezawa Hiroyuki Return-path: In-Reply-To: <50B85C8C.2030702@jp.fujitsu.com> Sender: owner-linux-aio@kvack.org List-Id: linux-fsdevel.vger.kernel.org On Fri, 30 Nov 2012 16:13:16 +0900 Kamezawa Hiroyuki wrote: > > What about futexes? > > > > IIUC, futex's key is now a pair of (mm,address) or (inode, pgoff). > Then, get_user_page() in futex.c will release the page by put_page(). > 'struct page' is just touched by get_futex_key() to obtain page->mapping info. Ah yes, that page is unpinned before syscall return. grep -rl get_user_pages . Gad. These should be audited. The great majority will be simple and OK, but drivers/media, drivers/infiniband and net/rds could be problematic. -- To unsubscribe, send a message with 'unsubscribe linux-aio' in the body to majordomo@kvack.org. For more info on Linux AIO, see: http://www.kvack.org/aio/ Don't email: aart@kvack.org