From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751674AbcB2OQ1 (ORCPT ); Mon, 29 Feb 2016 09:16:27 -0500 Received: from mail-wm0-f65.google.com ([74.125.82.65]:35539 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750772AbcB2OQZ (ORCPT ); Mon, 29 Feb 2016 09:16:25 -0500 Date: Mon, 29 Feb 2016 15:16:22 +0100 From: Michal Hocko To: "Kirill A. Shutemov" Cc: LKML , Andrew Morton , linux-mm@kvack.org, Alex Deucher , Alex Thorlton , Andrea Arcangeli , Andy Lutomirski , Benjamin LaHaise , Christian =?iso-8859-1?Q?K=F6nig?= , Daniel Vetter , Dave Hansen , David Airlie , Davidlohr Bueso , David Rientjes , "H . Peter Anvin" , Hugh Dickins , Ingo Molnar , Johannes Weiner , "Kirill A . Shutemov" , Konstantin Khlebnikov , linux-arch@vger.kernel.org, Mel Gorman , Oleg Nesterov , Peter Zijlstra , Petr Cermak , Thomas Gleixner Subject: Re: [PATCH 0/18] change mmap_sem taken for write killable Message-ID: <20160229141622.GC16930@dhcp22.suse.cz> References: <1456752417-9626-1-git-send-email-mhocko@kernel.org> <20160229140416.GA12506@node.shutemov.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160229140416.GA12506@node.shutemov.name> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 29-02-16 17:04:16, Kirill A. Shutemov wrote: [...] > > Most of the patches are really trivial because the lock is help from a > > shallow syscall paths where we can return EINTR trivially. Others seem > > to be easy as well as the callers are already handling fatal errors and > > bail and return to userspace which should be sufficient to handle the > > failure gracefully. I am not familiar with all those code paths so a > > deeper review is really appreciated. > > What about effect on userspace? IIUC, we would have now EINTR returned > from bunch of syscall, which haven't had this errno on the table before. > Should we care? Those function will return EINTR only when the current was _killed_ when we do not return to the userspace. So there shouldn't be any visible effect. -- Michal Hocko SUSE Labs From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Hocko Subject: Re: [PATCH 0/18] change mmap_sem taken for write killable Date: Mon, 29 Feb 2016 15:16:22 +0100 Message-ID: <20160229141622.GC16930@dhcp22.suse.cz> References: <1456752417-9626-1-git-send-email-mhocko@kernel.org> <20160229140416.GA12506@node.shutemov.name> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-wm0-f65.google.com ([74.125.82.65]:35539 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750772AbcB2OQZ (ORCPT ); Mon, 29 Feb 2016 09:16:25 -0500 Content-Disposition: inline In-Reply-To: <20160229140416.GA12506@node.shutemov.name> Sender: linux-arch-owner@vger.kernel.org List-ID: To: "Kirill A. Shutemov" Cc: LKML , Andrew Morton , linux-mm@kvack.org, Alex Deucher , Alex Thorlton , Andrea Arcangeli , Andy Lutomirski , Benjamin LaHaise , Christian =?iso-8859-1?Q?K=F6nig?= , Daniel Vetter , Dave Hansen , David Airlie , Davidlohr Bueso , David Rientjes , "H . Peter Anvin" , Hugh Dickins , Ingo Molnar , Johannes Weiner , "Kirill A . Shutemov" , Konstantin Khlebnikov , linux-arch@vger.kernel.org, Mel Gorman , Oleg Nesterov Pe On Mon 29-02-16 17:04:16, Kirill A. Shutemov wrote: [...] > > Most of the patches are really trivial because the lock is help from a > > shallow syscall paths where we can return EINTR trivially. Others seem > > to be easy as well as the callers are already handling fatal errors and > > bail and return to userspace which should be sufficient to handle the > > failure gracefully. I am not familiar with all those code paths so a > > deeper review is really appreciated. > > What about effect on userspace? IIUC, we would have now EINTR returned > from bunch of syscall, which haven't had this errno on the table before. > Should we care? Those function will return EINTR only when the current was _killed_ when we do not return to the userspace. So there shouldn't be any visible effect. -- Michal Hocko SUSE Labs From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f44.google.com (mail-wm0-f44.google.com [74.125.82.44]) by kanga.kvack.org (Postfix) with ESMTP id B3B8B828E1 for ; Mon, 29 Feb 2016 09:16:25 -0500 (EST) Received: by mail-wm0-f44.google.com with SMTP id n186so51391225wmn.1 for ; Mon, 29 Feb 2016 06:16:25 -0800 (PST) Date: Mon, 29 Feb 2016 15:16:22 +0100 From: Michal Hocko Subject: Re: [PATCH 0/18] change mmap_sem taken for write killable Message-ID: <20160229141622.GC16930@dhcp22.suse.cz> References: <1456752417-9626-1-git-send-email-mhocko@kernel.org> <20160229140416.GA12506@node.shutemov.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160229140416.GA12506@node.shutemov.name> Sender: owner-linux-mm@kvack.org List-ID: To: "Kirill A. Shutemov" Cc: LKML , Andrew Morton , linux-mm@kvack.org, Alex Deucher , Alex Thorlton , Andrea Arcangeli , Andy Lutomirski , Benjamin LaHaise , Christian =?iso-8859-1?Q?K=F6nig?= , Daniel Vetter , Dave Hansen , David Airlie , Davidlohr Bueso , David Rientjes , "H . Peter Anvin" , Hugh Dickins , Ingo Molnar , Johannes Weiner , "Kirill A . Shutemov" , Konstantin Khlebnikov , linux-arch@vger.kernel.org, Mel Gorman , Oleg Nesterov , Peter Zijlstra , Petr Cermak , Thomas Gleixner On Mon 29-02-16 17:04:16, Kirill A. Shutemov wrote: [...] > > Most of the patches are really trivial because the lock is help from a > > shallow syscall paths where we can return EINTR trivially. Others seem > > to be easy as well as the callers are already handling fatal errors and > > bail and return to userspace which should be sufficient to handle the > > failure gracefully. I am not familiar with all those code paths so a > > deeper review is really appreciated. > > What about effect on userspace? IIUC, we would have now EINTR returned > from bunch of syscall, which haven't had this errno on the table before. > Should we care? Those function will return EINTR only when the current was _killed_ when we do not return to the userspace. So there shouldn't be any visible effect. -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org