From: Gary Guo <gary@garyguo.net>
To: Andreas Hindborg <a.hindborg@kernel.org>
Cc: FUJITA Tomonori <fujita.tomonori@gmail.com>,
aliceryhl@google.com, lyude@redhat.com, boqun.feng@gmail.com,
will@kernel.org, peterz@infradead.org,
richard.henderson@linaro.org, mattst88@gmail.com,
linmag7@gmail.com, catalin.marinas@arm.com, ojeda@kernel.org,
bjorn3_gh@protonmail.com, lossin@kernel.org, tmgross@umich.edu,
dakr@kernel.org, mark.rutland@arm.com, frederic@kernel.org,
tglx@linutronix.de, anna-maria@linutronix.de, jstultz@google.com,
sboyd@kernel.org, viro@zeniv.linux.org.uk, brauner@kernel.org,
jack@suse.cz, linux-kernel@vger.kernel.org,
linux-alpha@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
rust-for-linux@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 4/5] rust: hrtimer: use READ_ONCE instead of read_volatile
Date: Tue, 6 Jan 2026 15:23:00 +0000 [thread overview]
Message-ID: <20260106152300.7fec3847.gary@garyguo.net> (raw)
In-Reply-To: <87ikdej4s1.fsf@t14s.mail-host-address-is-not-set>
On Tue, 06 Jan 2026 13:37:34 +0100
Andreas Hindborg <a.hindborg@kernel.org> wrote:
> "FUJITA Tomonori" <fujita.tomonori@gmail.com> writes:
> >
> > Sorry, of course this should be:
> >
> > +__rust_helper ktime_t rust_helper_hrtimer_get_expires(const struct hrtimer *timer)
> > +{
> > + return hrtimer_get_expires(timer);
> > +}
> >
>
> This is a potentially racy read. As far as I recall, we determined that
> using read_once is the proper way to handle the situation.
>
> I do not think it makes a difference that the read is done by C code.
If that's the case I think the C code should be fixed by inserting the
READ_ONCE?
Best,
Gary
next prev parent reply other threads:[~2026-01-06 15:23 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-12-31 12:22 [PATCH 0/5] Add READ_ONCE and WRITE_ONCE to Rust Alice Ryhl
2025-12-31 12:22 ` [PATCH 1/5] arch: add CONFIG_ARCH_USE_CUSTOM_READ_ONCE for arm64/alpha Alice Ryhl
2025-12-31 12:22 ` [PATCH 2/5] rust: sync: add READ_ONCE and WRITE_ONCE Alice Ryhl
2026-01-06 12:29 ` Andreas Hindborg
2026-01-06 12:53 ` Boqun Feng
2025-12-31 12:22 ` [PATCH 3/5] rust: sync: support using bool with READ_ONCE Alice Ryhl
2025-12-31 15:25 ` Gary Guo
2026-01-06 12:43 ` Peter Zijlstra
2026-01-06 12:51 ` Alice Ryhl
2026-01-06 18:12 ` Gary Guo
2026-01-07 8:33 ` Peter Zijlstra
2026-01-07 18:12 ` Gary Guo
2025-12-31 12:22 ` [PATCH 4/5] rust: hrtimer: use READ_ONCE instead of read_volatile Alice Ryhl
2026-01-01 2:11 ` FUJITA Tomonori
2026-01-01 4:00 ` FUJITA Tomonori
2026-01-06 12:37 ` Andreas Hindborg
2026-01-06 13:28 ` FUJITA Tomonori
2026-01-07 10:11 ` Andreas Hindborg
2026-01-07 11:22 ` FUJITA Tomonori
2026-01-07 18:21 ` Andreas Hindborg
2026-01-09 2:10 ` FUJITA Tomonori
2026-01-09 10:42 ` Andreas Hindborg
2026-01-07 11:51 ` Boqun Feng
2026-01-07 12:48 ` Andreas Hindborg
2026-01-06 15:23 ` Gary Guo [this message]
2026-01-06 18:43 ` Alice Ryhl
2026-01-07 0:47 ` John Hubbard
2026-01-07 1:08 ` Boqun Feng
2026-01-07 2:59 ` John Hubbard
2026-01-07 1:18 ` Boqun Feng
2025-12-31 12:22 ` [PATCH 5/5] rust: fs: " Alice Ryhl
2026-01-21 0:47 ` Boqun Feng
2025-12-31 15:12 ` [PATCH 0/5] Add READ_ONCE and WRITE_ONCE to Rust Gary Guo
2026-01-01 0:53 ` Alice Ryhl
2026-01-01 1:13 ` Boqun Feng
2026-01-06 12:41 ` Andreas Hindborg
2026-01-06 13:09 ` Boqun Feng
2026-01-06 14:56 ` Peter Zijlstra
2026-01-06 18:18 ` Paul E. McKenney
2026-01-06 19:28 ` Marco Elver
2026-01-09 2:09 ` Paul E. McKenney
2026-01-09 12:00 ` Marco Elver
2026-01-07 8:43 ` Peter Zijlstra
2026-01-07 19:17 ` Paul E. McKenney
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