linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: John Garry <john.garry@huawei.com>
To: Niklas Schnelle <schnelle@linux.ibm.com>,
	Arnd Bergmann <arnd@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	linux-arch <linux-arch@vger.kernel.org>,
	linux-pci <linux-pci@vger.kernel.org>,
	"Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>
Subject: Re: [GIT PULL 1/2] asm-generic: rework PCI I/O space access
Date: Fri, 17 Dec 2021 14:27:33 +0000	[thread overview]
Message-ID: <53746e42-23a2-049d-9b38-dcfbaaae728f@huawei.com> (raw)
In-Reply-To: <849d70bddde1cfcb3ab1163970a148ff447ee94b.camel@linux.ibm.com>

On 17/12/2021 13:52, Niklas Schnelle wrote:

Thanks for looking at this again.

>>> I have tested this on s390 with HAS_IOPORT=n and allyesconfig as well
>>> as running it with defconfig. I've also been using it on my Ryzen 3990X
>>> workstation with LEGACY_PCI=n for a few days. I do get about 60 MiB
>>> fewer modules compared with a similar config of v5.15.8. Hard to say
>>> which other systems might miss things of course.
>>>
>>> I have not yet worked on the discussed IOPORT_NATIVE flag. Mostly I'm
>>> wondering two things. For one it feels like that could be a separate
>>> change on top since HAS_IOPORT + LEGACY_PCI is already quite big.
>>> Secondly I'm wondering about good ways of identifying such drivers and
>>> how much this overlaps with the ISA config flag.

I was interesting in the IOPORT_NATIVE flag (or whatever we call it) as 
it solves the problem of drivers which "unconditionally do inb()/outb() 
without checking the validity of the address using firmware or other 
methods first" being built for (and loaded on and crashing) unsuitable 
systems. Such a problem is in [0]

So if we want to support that later, then it seems that someone would 
need to go back and re-edit many same driver Kconfigs – like hwon, for 
example. I think it's better to avoid that and do it now.

Arnd, any opinion on that?

I'm happy to help with that effort.

[0] 
https://lore.kernel.org/lkml/1610729929-188490-1-git-send-email-john.garry@huawei.com/

Thanks,
John

  parent reply	other threads:[~2021-12-17 14:28 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-02 13:47 [GIT PULL 1/2] asm-generic: rework PCI I/O space access Arnd Bergmann
2021-07-02 13:49 ` [GIT PULL 2/2] asm-generic: Unify asm/unaligned.h around struct helper Arnd Bergmann
2021-07-02 20:13   ` pr-tracker-bot
2021-07-02 19:42 ` [GIT PULL 1/2] asm-generic: rework PCI I/O space access Linus Torvalds
2021-07-03 12:12   ` Arnd Bergmann
2021-07-05 10:06     ` Arnd Bergmann
2021-08-03  9:46       ` John Garry
2021-08-03 10:06         ` Arnd Bergmann
2021-08-03 11:23           ` John Garry
2021-08-03 12:15             ` Arnd Bergmann
2021-08-04  7:55               ` John Garry
2021-08-04  8:52                 ` Arnd Bergmann
2021-08-10  9:19                   ` John Garry
2021-08-10 11:33                     ` Arnd Bergmann
2021-09-03  8:31                       ` Niklas Schnelle
2021-12-17 13:19                       ` Niklas Schnelle
2021-12-17 13:32                         ` Arnd Bergmann
2021-12-17 13:52                           ` Niklas Schnelle
2021-12-17 14:05                             ` Arnd Bergmann
2021-12-17 14:27                             ` John Garry [this message]
2021-12-17 14:32                               ` Arnd Bergmann
2021-12-17 15:27                                 ` John Garry
2021-12-17 15:55                                   ` Arnd Bergmann
2021-12-17 16:30                                     ` John Garry
2021-12-20  9:27                                       ` Niklas Schnelle
2021-12-21 16:48                                         ` John Garry
2021-12-21 16:57                                           ` Niklas Schnelle
2021-12-19 14:23                               ` David Laight
2021-12-21 16:21                                 ` John Garry
2021-07-05 12:40     ` Niklas Schnelle

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=53746e42-23a2-049d-9b38-dcfbaaae728f@huawei.com \
    --to=john.garry@huawei.com \
    --cc=arnd@kernel.org \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=schnelle@linux.ibm.com \
    --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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).