From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 1/2] mm, Make __get_user_pages return -EHWPOISON for HWPOISON page optionally Date: Thu, 13 Jan 2011 12:43:03 +0200 Message-ID: <4D2ED737.6050802@redhat.com> References: <1294908168.4596.58.camel@yhuang-dev> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" , Andi Kleen , Tony Luck , Dean Nelson , Andrew Morton To: Huang Ying Return-path: In-Reply-To: <1294908168.4596.58.camel@yhuang-dev> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 01/13/2011 10:42 AM, Huang Ying wrote: > Make __get_user_pages return -EHWPOISON for HWPOISON page only if > FOLL_HWPOISON is specified. With this patch, the interested callers > can distinguish HWPOISON page from general FAULT page, while other > callers will still get -EFAULT for pages, so the user space interface > need not to be changed. > > get_user_pages_hwpoison is added as a variant of get_user_pages that > can return -EHWPOISON for HWPOISON page. > > This feature is needed by KVM, where UCR MCE should be relayed to > guest for HWPOISON page, while instruction emulation and MMIO will be > tried for general FAULT page. > > The idea comes from Andrew Morton. > > Signed-off-by: Huang Ying > Cc: Andrew Morton > > +#ifdef CONFIG_MEMORY_FAILURE > +int get_user_pages_hwpoison(struct task_struct *tsk, struct mm_struct *mm, > + unsigned long start, int nr_pages, int write, > + int force, struct page **pages, > + struct vm_area_struct **vmas); > +#else Since we'd also like to add get_user_pages_noio(), perhaps adding a flags field to get_user_pages() is better. -- error compiling committee.c: too many arguments to function