All of lore.kernel.org
 help / color / mirror / Atom feed
From: Willy Tarreau <w@1wt.eu>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Denis Efremov <efremov@linux.com>, Jens Axboe <axboe@kernel.dk>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-block <linux-block@vger.kernel.org>
Subject: Re: [PATCH 01/10] floppy: cleanup: expand macro FDCS
Date: Tue, 25 Feb 2020 19:15:41 +0100	[thread overview]
Message-ID: <20200225181541.GA1138@1wt.eu> (raw)
In-Reply-To: <CAHk-=wggnfCR2JcC-U9LxfeBo2UMagd-neEs8PwDHsGVfLfS=Q@mail.gmail.com>

On Tue, Feb 25, 2020 at 10:08:51AM -0800, Linus Torvalds wrote:
> On Tue, Feb 25, 2020 at 7:22 AM Denis Efremov <efremov@linux.com> wrote:
> >
> > I think that for the first attempt changing will be enough:
> > -static int fdc;                        /* current fdc */
> > +static int current_fdc;                        /* current fdc */
> > and
> > -#define FD_IOPORT fdc_state[fdc].address
> > +#define FD_IOPORT fdc_state[current_fdc].address
> 
> Please don't do this blindly - ie without verifying that there are no
> cases of that "local fdc variable shadowing" issue.

That's exactly what I'm doing. In fact I first renamed the variable
and am manually checking all places which do not compile anymore.
Hence the surprizes.

> Of course, such a verification might be as easy as "generates exact
> same code" rather than looking at every use.

That's exactly what I'm doing.

> And btw, don't worry too much about this being in an UAPI file. I'm
> pretty sure that's because of specialty programs that use the magical
> ioctls to do special formatting. They want the special commands
> (FD_FORMAT etc), but I don't think they really use the port addresses.
> 
> So I think it's in a UAPI file entirely by mistake.

OK this will help me, thanks for the hint :-)

> We should at least try moving those bits to the floppy.c file and
> remove it from the header file.

Makes sense.

> For example, doing a Debian code search on "FDPATCHES" doesn't find
> any user space hits. Searching for "FD_STATUS" gets a lot of hits, but
> thos all seem to be because it's a symbol used by user space programs,
> ("file descriptor status"), not because those hits actually used the
> fdreg.h header file.
> 
> So we can remove at least the FD_IOPORT mess from the header file, I bet.
> 
> Worst case - if somebody finds some case that uses them, we can put it back.

I like that. And at least we'll know how they use it (likely without the
dependency on fdc).

Thanks,
Willy

  reply	other threads:[~2020-02-25 18:15 UTC|newest]

Thread overview: 45+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-24 21:23 [PATCH 00/10] floppy driver cleanups (deobfuscation) Willy Tarreau
2020-02-24 21:23 ` [PATCH 01/10] floppy: cleanup: expand macro FDCS Willy Tarreau
2020-02-24 21:53   ` Linus Torvalds
2020-02-24 23:13     ` Denis Efremov
2020-02-25  3:45       ` Willy Tarreau
2020-02-25  7:14         ` Denis Efremov
2020-02-25 14:02           ` Willy Tarreau
2020-02-25 15:22             ` Denis Efremov
2020-02-25 15:39               ` Denis Efremov
2020-02-25 16:12                 ` Willy Tarreau
2020-02-25 18:02               ` Willy Tarreau
2020-02-25 18:08                 ` Willy Tarreau
2020-02-25 18:08               ` Linus Torvalds
2020-02-25 18:15                 ` Willy Tarreau [this message]
2020-02-25 18:27                   ` Linus Torvalds
2020-02-26  8:18                 ` Willy Tarreau
2020-02-25 11:37   ` Denis Efremov
2020-02-24 21:23 ` [PATCH 02/10] floppy: cleanup: expand macro UFDCS Willy Tarreau
2020-02-24 21:23 ` [PATCH 03/10] floppy: cleanup: expand macro UDP Willy Tarreau
2020-02-24 21:23 ` [PATCH 04/10] floppy: cleanup: expand macro UDRS Willy Tarreau
2020-02-24 21:23 ` [PATCH 05/10] floppy: cleanup: expand macro UDRWE Willy Tarreau
2020-02-24 21:23 ` [PATCH 06/10] floppy: cleanup: expand macro DP Willy Tarreau
2020-02-24 21:23 ` [PATCH 07/10] floppy: cleanup: expand macro DRS Willy Tarreau
2020-02-24 21:23 ` [PATCH 08/10] floppy: cleanup: expand macro DRWE Willy Tarreau
2020-02-24 21:23 ` [PATCH 09/10] floppy: cleanup: expand the R/W / format command macros Willy Tarreau
2020-02-24 21:23 ` [PATCH 10/10] floppy: cleanup: expand the reply_buffer macros Willy Tarreau
2020-02-26  8:07 ` [PATCH 11/16] floppy: remove dead code for drives scanning on ARM Willy Tarreau
2020-02-26  8:07   ` [PATCH 12/16] floppy: remove incomplete support for second FDC from ARM code Willy Tarreau
2020-02-29 16:38     ` Denis Efremov
2020-02-26  8:07   ` [PATCH 13/16] floppy: prepare ARM code to simplify base address separation Willy Tarreau
2020-02-26  8:07   ` [PATCH 14/16] floppy: introduce new functions fdc_inb() and fdc_outb() Willy Tarreau
2020-02-26  8:07   ` [PATCH 15/16] floppy: separate the FDC's base address from its registers Willy Tarreau
2020-02-26 15:36     ` Denis Efremov
2020-02-26 15:46       ` Willy Tarreau
2020-02-26  8:07   ` [PATCH 16/16] floppy: rename the global "fdc" variable to "current_fdc" Willy Tarreau
2020-03-01  8:21   ` [PATCH 11/16] floppy: remove dead code for drives scanning on ARM Denis Efremov
2020-03-01  8:59     ` Willy Tarreau
2020-02-26 14:57 ` [PATCH 00/10] floppy driver cleanups (deobfuscation) Denis Efremov
2020-02-26 17:49   ` Linus Torvalds
2020-02-26 18:41     ` Willy Tarreau
2020-02-29 14:13     ` Willy Tarreau
2020-02-29 15:58       ` Linus Torvalds
2020-02-29 23:19         ` Ondrej Zary
2020-03-01  6:46           ` Willy Tarreau
2020-03-01 17:01             ` Ondrej Zary

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=20200225181541.GA1138@1wt.eu \
    --to=w@1wt.eu \
    --cc=axboe@kernel.dk \
    --cc=efremov@linux.com \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --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.