public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Andreas Schwab <schwab@suse.de>
To: "Török Edwin" <edwintorok@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Linux Kernel <linux-kernel@vger.kernel.org>,
	LLVM Developers Mailing List <llvmdev@cs.uiuc.edu>
Subject: Re: inline asm semantics: output constraint width smaller than input
Date: Sat, 24 Jan 2009 21:07:02 +0100	[thread overview]
Message-ID: <jebptw4gex.fsf@sykes.suse.de> (raw)
In-Reply-To: <497B408C.20802@gmail.com> ("Török Edwin"'s message of "Sat, 24 Jan 2009 18:23:40 +0200")

Török Edwin <edwintorok@gmail.com> writes:

> @@ -239,11 +239,13 @@ extern void __put_user_8(void);
>   */
>  #define put_user(x, ptr)                    \
>  ({                                \
> -    int __ret_pu;                        \
> +    __typeof__(*(ptr)) __ret_pu;                \
>      __typeof__(*(ptr)) __pu_val;                \
>      __chk_user_ptr(ptr);                    \
>      might_fault();                        \
>      __pu_val = x;                        \
> +       /* return value is 0 or -EFAULT, both fit in 1 byte, and \
> +    * are sign-extendable to int */                \

That does not work when *ptr is unsigned (char or short).

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
PGP key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

      parent reply	other threads:[~2009-01-24 20:07 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-01-23 17:57 inline asm semantics: output constraint width smaller than input Török Edwin
2009-01-23 18:17 ` Ingo Molnar
2009-01-23 18:21   ` H. Peter Anvin
2009-01-23 18:27   ` Török Edwin
2009-01-23 18:30     ` Ingo Molnar
2009-01-23 18:52       ` Török Edwin
2009-01-23 20:42         ` Török Edwin
2009-01-24 16:23     ` Török Edwin
2009-01-24 17:27       ` Ingo Molnar
2009-01-24 18:57         ` Török Edwin
2009-01-24 21:25           ` [LLVMdev] " Mike Stump
2009-01-24 19:23         ` Chris Lattner
2009-01-24 21:10           ` H. Peter Anvin
2009-01-27 19:42         ` Duncan Sands
2009-01-27 21:25           ` H. Peter Anvin
2009-01-28  1:45             ` Kyle Moffett
2009-01-28  1:56               ` H. Peter Anvin
2009-01-28 13:28                 ` Kyle Moffett
2009-01-28 17:29                   ` H. Peter Anvin
2009-01-28 19:27                     ` Kyle Moffett
2009-01-28 20:59                       ` H. Peter Anvin
2009-01-24 20:07       ` Andreas Schwab [this message]

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=jebptw4gex.fsf@sykes.suse.de \
    --to=schwab@suse.de \
    --cc=edwintorok@gmail.com \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=llvmdev@cs.uiuc.edu \
    --cc=mingo@elte.hu \
    --cc=tglx@linutronix.de \
    /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