From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f71.google.com (mail-wm0-f71.google.com [74.125.82.71]) by kanga.kvack.org (Postfix) with ESMTP id 8A7856B026B for ; Tue, 24 Jan 2017 17:22:20 -0500 (EST) Received: by mail-wm0-f71.google.com with SMTP id r126so31300799wmr.2 for ; Tue, 24 Jan 2017 14:22:20 -0800 (PST) Received: from mail-wm0-x244.google.com (mail-wm0-x244.google.com. [2a00:1450:400c:c09::244]) by mx.google.com with ESMTPS id p26si24359611wrp.311.2017.01.24.14.22.19 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 24 Jan 2017 14:22:19 -0800 (PST) Received: by mail-wm0-x244.google.com with SMTP id r144so38049135wme.0 for ; Tue, 24 Jan 2017 14:22:19 -0800 (PST) Date: Wed, 25 Jan 2017 01:22:17 +0300 From: "Kirill A. Shutemov" Subject: Re: [PATCH 01/12] uprobes: split THPs before trying replace them Message-ID: <20170124222217.GB19920@node.shutemov.name> References: <20170124162824.91275-1-kirill.shutemov@linux.intel.com> <20170124162824.91275-2-kirill.shutemov@linux.intel.com> <20170124132849.73135e8c6e9572be00dbbe79@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170124132849.73135e8c6e9572be00dbbe79@linux-foundation.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: "Kirill A. Shutemov" , Andrea Arcangeli , Hugh Dickins , Rik van Riel , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Oleg Nesterov , Peter Zijlstra On Tue, Jan 24, 2017 at 01:28:49PM -0800, Andrew Morton wrote: > On Tue, 24 Jan 2017 19:28:13 +0300 "Kirill A. Shutemov" wrote: > > > For THPs page_check_address() always fails. It's better to split them > > first before trying to replace. > > So what does this mean. uprobes simply fails to work when trying to > place a probe into a THP memory region? Looks like we can end up with endless retry loop in uprobe_write_opcode(). > How come nobody noticed (and reported) this when using the feature? I guess it's not often used for anon memory. -- Kirill A. Shutemov -- 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