From: Ingo Molnar <mingo@elte.hu>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>,
hans.rosenfeld@amd.com, linux-kernel@vger.kernel.org,
Thomas Gleixner <tglx@linutronix.de>,
"H. Peter Anvin" <hpa@zytor.com>
Subject: Re: bisected boot regression post 2.6.25-rc3.. please revert
Date: Sun, 9 Mar 2008 19:57:52 +0100 [thread overview]
Message-ID: <20080309185752.GA9548@elte.hu> (raw)
In-Reply-To: <alpine.LFD.1.00.0803091007560.5896@woody.linux-foundation.org>
* Linus Torvalds <torvalds@linux-foundation.org> wrote:
> So I would *very* strongly instead argue:
>
> - "unsigned long" is the native kernel type for all address manipulation,
> and thus "PAGE_SIZE" and "PAGE_MASK" should continue to have that type.
>
> - anything that uses any other type without explicitly making sure it's
> safe is mis-using those macros. IOW, PAGE_MASk was *never* a type that
> had anything what-so-ever to do with page table entry bits, and this is
> purely a page table entry issue!
>
> So my suggested patch would:
>
> - make the page table code use a specific mask that it builds up itself,
> and makes sure it's of the right type and has the rigth value in
> whatever type "struct pte_entry" is. The fact that "pte_val()" is
> larger than "unsigned long" on x86-32 is very clearly a PTE issue,
> *not* an issue for PAGE_SIZE or PAGE_MASK.
yeah, indeed my patch was sloppy, i didnt think it through - i fell for
the lure of the easy-looking 'PAGE_SIZE is small, sign-extend it' hack.
Will do it cleanly and will also clean up all the pte/address/pgprot
type mixing that currently goes on in this maze of macros.
Ingo
next prev parent reply other threads:[~2008-03-09 18:58 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-03-01 18:56 bisected boot regression post 2.6.25-rc3.. please revert Arjan van de Ven
2008-03-03 7:46 ` Ingo Molnar
2008-03-03 9:13 ` Ingo Molnar
2008-03-03 16:41 ` Arjan van de Ven
2008-03-03 17:40 ` Ingo Molnar
2008-03-03 17:51 ` Nish Aravamudan
2008-03-03 17:55 ` Ingo Molnar
2008-03-03 17:58 ` H. Peter Anvin
2008-03-03 18:36 ` Arjan van de Ven
2008-03-03 18:44 ` Linus Torvalds
2008-03-03 22:00 ` Arjan van de Ven
2008-03-04 1:05 ` Arjan van de Ven
2008-03-04 6:53 ` Ingo Molnar
2008-03-05 15:35 ` Arjan van de Ven
2008-03-09 11:56 ` Ingo Molnar
2008-03-09 17:27 ` Linus Torvalds
2008-03-09 18:57 ` Ingo Molnar [this message]
2008-03-10 2:45 ` Jeremy Fitzhardinge
2008-03-10 4:35 ` Paul Mackerras
2008-03-03 21:13 ` Segher Boessenkool
2008-03-03 21:22 ` Segher Boessenkool
2008-03-03 22:33 ` Segher Boessenkool
2008-03-03 22:55 ` H. Peter Anvin
2008-03-03 22:56 ` Jeremy Fitzhardinge
2008-03-03 23:04 ` H. Peter Anvin
2008-03-04 6:58 ` Ingo Molnar
2008-03-03 17:15 ` Nish Aravamudan
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=20080309185752.GA9548@elte.hu \
--to=mingo@elte.hu \
--cc=arjan@linux.intel.com \
--cc=hans.rosenfeld@amd.com \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.