mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Andrew Morton <andrewm@uow.edu.au>
To: Mike Galbraith <mikeg@wen-online.de>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [testcase] madvise->semaphore deadlock 2.4.0
Date: Tue, 09 Jan 2001 23:15:48 +1100	[thread overview]
Message-ID: <3A5B00F4.55FB83FE@uow.edu.au> (raw)
In-Reply-To: <Pine.Linu.4.10.10101091113020.2510-100000@mikeg.weiden.de>

Mike Galbraith wrote:
> 
> Greetings,
> 
> While trying to configure ftpsearch, the process hangs while running
> it's madvise confidence test below.  It appears to be taking a fault
> in madvise_fixup_middle():atomic_add(2, &vma->vm_file->f_count) and
> immediately deadlocking forever on mm->mmap_sem per IKD.  (Virgin 2.4.0
> agrees)
>

This should fix it.

We're still in disagreement with the HPUX 11 manpage though.
HP say that MADV_DONTNEED requires an underlying file,
and thus implies that MADV_WILLNEED doesn't need an
underlying file.  We have it the other way round, which
seems more sensible.


--- linux-2.4.0/mm/filemap.c	Fri Jan  5 21:37:20 2001
+++ linux-akpm/mm/filemap.c	Tue Jan  9 23:05:00 2001
@@ -1835,7 +1835,8 @@
 	n->vm_end = end;
 	setup_read_behavior(n, behavior);
 	n->vm_raend = 0;
-	get_file(n->vm_file);
+	if (n->vm_file)
+		get_file(n->vm_file);
 	if (n->vm_ops && n->vm_ops->open)
 		n->vm_ops->open(n);
 	lock_vma_mappings(vma);
@@ -1861,7 +1862,8 @@
 	n->vm_pgoff += (n->vm_start - vma->vm_start) >> PAGE_SHIFT;
 	setup_read_behavior(n, behavior);
 	n->vm_raend = 0;
-	get_file(n->vm_file);
+	if (n->vm_file)
+		get_file(n->vm_file);
 	if (n->vm_ops && n->vm_ops->open)
 		n->vm_ops->open(n);
 	lock_vma_mappings(vma);
@@ -1893,7 +1895,8 @@
 	right->vm_pgoff += (right->vm_start - left->vm_start) >> PAGE_SHIFT;
 	left->vm_raend = 0;
 	right->vm_raend = 0;
-	atomic_add(2, &vma->vm_file->f_count);
+	if (vma->vm_file)
+		atomic_add(2, &vma->vm_file->f_count);
 
 	if (vma->vm_ops && vma->vm_ops->open) {
 		vma->vm_ops->open(left);
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/

  reply	other threads:[~2001-01-09 12:09 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-01-09 10:32 Mike Galbraith
2001-01-09 12:15 ` Andrew Morton [this message]
2001-01-09 13:29   ` Mike Galbraith

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=3A5B00F4.55FB83FE@uow.edu.au \
    --to=andrewm@uow.edu.au \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mikeg@wen-online.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®