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Date: Wed, 26 Feb 2025 16:26:55 -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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Subject: Re: C aggregate passing (Rust kernel policy)
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On Wed, 26 Feb 2025 13:14:30 -0800
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> Similarly, if the source code has a single read, the compiler had
> better not turn that into two reads (because of some register pressure
> issue). That would *ALSO* be a bug, because of the whole TOCTOU issue
> (ie the source code may have had one single access, done sanity
> testing on the value before using it, and if the compiler turned it
> all into "read+sanity test" and "read+use", the compiler is
> introducing behavioral differences).

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()?

-- Steve