Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753616Ab3JLUc4 (ORCPT ); Sat, 12 Oct 2013 16:32:56 -0400 Received: from mail-ee0-f50.google.com ([74.125.83.50]:54214 "EHLO mail-ee0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752744Ab3JLUcy (ORCPT ); Sat, 12 Oct 2013 16:32:54 -0400 Date: Sat, 12 Oct 2013 23:32:50 +0300 From: Alexey Dobriyan To: HATAYAMA Daisuke Cc: Michael Holzheu , "David S. Miller" , Vivek Goyal , Jan Willeke , Linux Kernel , kexec@lists.infradead.org Subject: Re: mmap for /proc/vmcore broken since 3.12-rc1 Message-ID: <20131012203250.GA3458@p183.telecom.by> References: <20131002140356.63706540@holzheu> <524D0ADF.2010507@jp.fujitsu.com> <52521FA5.3040101@jp.fujitsu.com> <52552C9F.2030404@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <52552C9F.2030404@jp.fujitsu.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2035 Lines: 53 On Wed, Oct 09, 2013 at 07:14:55PM +0900, HATAYAMA Daisuke wrote: > Hello, > > (2013/10/08 21:49), Alexey Dobriyan wrote: > > On Mon, Oct 7, 2013 at 5:42 AM, HATAYAMA Daisuke > > wrote: > > > >> +static unsigned long > >> +get_unmapped_area_vmcore(struct file *filp, unsigned long addr, > >> + unsigned long len, unsigned long pgoff, > >> + unsigned long flags) > >> +{ > >> +#ifdef CONFIG_MMU > >> + return current->mm->get_unmapped_area(filp, addr, len, pgoff, > >> flags); > >> +#else > >> + return -EIO; > >> +#endif > >> +} > >> + > >> static const struct file_operations proc_vmcore_operations = { > >> .read = read_vmcore, > >> .llseek = default_llseek, > >> .mmap = mmap_vmcore, > >> + .get_unmapped_area = get_unmapped_area_vmcore, > > > > I think current->mm->get_unmapped_area should be used by core proc code. > > What do you actually suggest here? You mean moving this code in proc code? > I don't think you suggest so. Please, try this patch, I don't have kexec setup handy. --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -291,7 +291,11 @@ static unsigned long proc_reg_get_unmapped_area(struct file *file, unsigned long int rv = -EIO; unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); if (use_pde(pde)) { - get_unmapped_area = pde->proc_fops->get_unmapped_area; + get_unmapped_area = current->mm->get_unmapped_area; +#ifdef CONFIG_MMU + if (pde->proc_fops->get_unmapped_area) + get_unmapped_area = pde->proc_fops->get_unmapped_area; +#endif if (get_unmapped_area) rv = get_unmapped_area(file, orig_addr, len, pgoff, flags); unuse_pde(pde); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/