mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: "Adam J. Richter" <adam@yggdrasil.com>
To: linux-kernel@vger.kernel.org
Subject: Re: 2.4.3-pre6: agpart.o causes arch/i386/mm/ioremap.c hang
Date: Fri, 23 Mar 2001 01:52:07 -0800	[thread overview]
Message-ID: <200103230952.BAA06705@adam.yggdrasil.com> (raw)

I wrote:

>	Under linux-2.4.3-pre6 compiled for SMP, loading agpgart.o
>hangs the system in remap_area_pages (arch/i386/mm/ioremap.c) at
>the call to spin_lock(&init_mm.page_table_lock), which is not in 2.4.2.
[...]
>	agp_backend_initialize
>	agp_generic_create_gatt_table
>	io_remap_nocache
>	__ioremap
>	remap_area_pages
[...]


>	I'm rebuilding the kernel now with a modified spin_lock()
>routine that should tell me who acquired the lock previously [...]

	 In case anyone is interested, the conflicting lock of
init_mm.page_table_lock was acquired in line 1318 of mm/memory.c,
in pte_alloc.

	One way that this might be happening is that it looks like
no page_table_lock is every acquired by vmalloc, which results in
the following call graph:

	vmalloc
	__vmalloc
	vmalloc_area_pages
	alloc_area_pmd
	pte_alloc ...which assumes (here incorrectly) that
		mm->page_table_lock is held, and sometimes releases
		and reacquires mm->page_table_lock.

	I will attempt to analyze this further tomorrow if nobody
beats me to it.

Adam J. Richter     __     ______________   4880 Stevens Creek Blvd, Suite 104
adam@yggdrasil.com     \ /                  San Jose, California 95129-1034
+1 408 261-6630         | g g d r a s i l   United States of America
fax +1 408 261-6631      "Free Software For The Rest Of Us."

             reply	other threads:[~2001-03-23  9:53 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-03-23  9:52 Adam J. Richter [this message]
2001-03-23 12:44 ` [patch] " Andrew Morton
  -- strict thread matches above, loose matches on Subject: below --
2001-03-23  9:10 Adam J. Richter

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=200103230952.BAA06705@adam.yggdrasil.com \
    --to=adam@yggdrasil.com \
    --cc=linux-kernel@vger.kernel.org \
    /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®