Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756499Ab0FATAG (ORCPT ); Tue, 1 Jun 2010 15:00:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51613 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751694Ab0FATAD (ORCPT ); Tue, 1 Jun 2010 15:00:03 -0400 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells Subject: [PATCH] NOMMU: Add '[stack]' label to /proc/pid/maps output To: torvalds@osdl.org, akpm@linux-foundation.org Cc: uclinux-dev@uclinux.org, linux-kernel@vger.kernel.org, uclinux-dist-devel@blackfin.uclinux.org, Mike Frysinger , David Howells Date: Tue, 01 Jun 2010 19:59:37 +0100 Message-ID: <20100601185937.5188.77506.stgit@warthog.procyon.org.uk> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2686 Lines: 85 From: Mike Frysinger Add support to the NOMMU /proc/pid/maps file to show which mapping is the stack of the original thread after execve. This is largely based on the MMU code. Subsidiary thread stacks are not indicated. For FDPIC, we now get: root:/> cat /proc/self/maps 02064000-02067ccc rw-p 0004d000 00:01 22 /bin/busybox 0206e000-0206f35c rw-p 00006000 00:01 295 /lib/ld-uClibc.so.0 025f0000-025f6f0c r-xs 00000000 00:01 295 /lib/ld-uClibc.so.0 02680000-026ba6b0 r-xs 00000000 00:01 297 /lib/libc.so.0 02700000-0274d384 r-xs 00000000 00:01 22 /bin/busybox 02816000-02817000 rw-p 00000000 00:00 0 02848000-0284c0d8 rw-p 00000000 00:00 0 02860000-02880000 rw-p 00000000 00:00 0 [stack] The semi-downside here is that for FLAT, we get: root:/> cat /proc/155/maps 029f0000-029f9000 rwxp 00000000 00:00 0 [stack] The reason being that FLAT combines a whole lot of stuff into one map (including the stack). But this isn't any worse than the current output (which is nothing), so screw it. Signed-off-by: Mike Frysinger Signed-off-by: David Howells --- fs/proc/task_nommu.c | 20 ++++++++++++++++---- 1 files changed, 16 insertions(+), 4 deletions(-) diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c index 46d4b5d..cb6306e 100644 --- a/fs/proc/task_nommu.c +++ b/fs/proc/task_nommu.c @@ -122,11 +122,20 @@ int task_statm(struct mm_struct *mm, int *shared, int *text, return size; } +static void pad_len_spaces(struct seq_file *m, int len) +{ + len = 25 + sizeof(void*) * 6 - len; + if (len < 1) + len = 1; + seq_printf(m, "%*c", len, ' '); +} + /* * display a single VMA to a sequenced file */ static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma) { + struct mm_struct *mm = vma->vm_mm; unsigned long ino = 0; struct file *file; dev_t dev = 0; @@ -155,11 +164,14 @@ static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma) MAJOR(dev), MINOR(dev), ino, &len); if (file) { - len = 25 + sizeof(void *) * 6 - len; - if (len < 1) - len = 1; - seq_printf(m, "%*c", len, ' '); + pad_len_spaces(m, len); seq_path(m, &file->f_path, ""); + } else if (mm) { + if (vma->vm_start <= mm->start_stack && + vma->vm_end >= mm->start_stack) { + pad_len_spaces(m, len); + seq_puts(m, "[stack]"); + } } seq_putc(m, '\n'); -- 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/