From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752328AbeCVFXt (ORCPT ); Thu, 22 Mar 2018 01:23:49 -0400 Received: from mail-pl0-f66.google.com ([209.85.160.66]:34761 "EHLO mail-pl0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752042AbeCVFXr (ORCPT ); Thu, 22 Mar 2018 01:23:47 -0400 X-Google-Smtp-Source: AG47ELsUgIPYt/PDcvTDx/od040rVUnL7QVmYEXSsBXdP8jylwjppZpkXfPhYrGedcXKxb9ak1gW1Q== From: Joel Stanley To: Jonathan Corbet , "Tobin C . Harding" Cc: Michael Ellerman , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] Documentation: Mention why %p prints ptrval Date: Thu, 22 Mar 2018 15:53:36 +1030 Message-Id: <20180322052336.1001-1-joel@jms.id.au> X-Mailer: git-send-email 2.15.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When debugging recent kernels, people will see '(ptrval)' but there isn't much information as to what that means. Briefly describe why it's there. Signed-off-by: Joel Stanley --- Documentation/core-api/printk-formats.rst | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/Documentation/core-api/printk-formats.rst b/Documentation/core-api/printk-formats.rst index 934559b3c130..eb30efdd2e78 100644 --- a/Documentation/core-api/printk-formats.rst +++ b/Documentation/core-api/printk-formats.rst @@ -60,8 +60,8 @@ Plain Pointers Pointers printed without a specifier extension (i.e unadorned %p) are hashed to prevent leaking information about the kernel memory layout. This has the added benefit of providing a unique identifier. On 64-bit machines -the first 32 bits are zeroed. If you *really* want the address see %px -below. +the first 32 bits are zeroed. The kernel will print ``(ptrval)`` until it +gathers enough entropy. If you *really* want the address see %px below. Symbols/Function Pointers ------------------------- -- 2.15.1