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Date: Wed, 26 Feb 2025 16:56:19 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Uecker <uecker@tugraz.at>, Ralf Jung <post@ralfj.de>, "Paul E.
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 ksummit@lists.linux.dev, linux-kernel@vger.kernel.org,
 miguel.ojeda.sandonis@gmail.com, rust-for-linux@vger.kernel.org
Subject: Re: C aggregate passing (Rust kernel policy)
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On Wed, 26 Feb 2025 13:42:29 -0800
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Wed, 26 Feb 2025 at 13:26, Steven Rostedt <rostedt@goodmis.org> wrote:
> >
> > As a bystander here, I just want to ask, do you mean basically to treat all
> > reads as READ_ONCE() and all writes as WRITE_ONCE()?  
> 
> Absolutely not.
> 
> I thought I made that clear:

Sorry, I didn't make myself clear. I shouldn't have said "all reads". What
I meant was the the "initial read".

Basically:

	r = READ_ONCE(*p);

and use what 'r' is from then on.

Where the compiler reads the source once and works with what it got.

To keep it from changing:

	r = *p;
	if (r > 1000)
		goto out;
	x = r;

to:

	if (*p > 1000)
		goto out;
	x = *p;


-- Steve