From: "Raymond B. Jennings III" <raymondj@watson.ibm.com>
To: linux-mm@kvack.org
Subject: Hole in kernel virtual address space.
Date: Mon, 07 Jan 2002 13:37:05 -0500 [thread overview]
Message-ID: <3C39EAD1.20CDF9CE@watson.ibm.com> (raw)
I've asked this question in the past but have yet to get any insight to
it.
Basically there appears to be a hole when HIGHMEM is turned on in the
kernel.
With HIGHMEM turned off:
VMALLOC_END = FIXADDR_START - 2*PAGE_SIZE
VMALLOC_END = (FFFFE000h - 4*PAGE_SIZE) - 2*PAGE_SIZE
(Pretty close to the 4GB boundary)
With HIGHMEM turned on:
VMALLOC_END = PKMAP_BASE - 2*PAGE_SIZE
I realize you need room for the pkmap_count array but the array only
allows for 1024 pages. If PKMAP_BASE = FE000000h then this fills the
address space upto
FE400000. What is being used in the remaining section of the address
space? Thanks.
--
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/
reply other threads:[~2002-01-07 18:33 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=3C39EAD1.20CDF9CE@watson.ibm.com \
--to=raymondj@watson.ibm.com \
--cc=linux-mm@kvack.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