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Date:   Fri, 8 Dec 2023 08:43:19 -0800
From:   Boqun Feng <boqun.feng@gmail.com>
To:     Benno Lossin <benno.lossin@proton.me>
Cc:     Alice Ryhl <aliceryhl@google.com>, Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Gary Guo <gary@garyguo.net>,
        =?iso-8859-1?Q?Bj=F6rn?= Roy Baron <bjorn3_gh@protonmail.com>,
        Andreas Hindborg <a.hindborg@samsung.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <brauner@kernel.org>,
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        Thomas Gleixner <tglx@linutronix.de>,
        Daniel Xu <dxu@dxuuu.xyz>, linux-kernel@vger.kernel.org,
        rust-for-linux@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v2 5/7] rust: file: add `Kuid` wrapper
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On Fri, Dec 08, 2023 at 04:40:09PM +0000, Benno Lossin wrote:
> On 12/6/23 12:59, Alice Ryhl wrote:
> > +    /// Returns the given task's pid in the current pid namespace.
> > +    pub fn pid_in_current_ns(&self) -> Pid {
> > +        // SAFETY: Calling `task_active_pid_ns` with the current task is always safe.
> > +        let namespace = unsafe { bindings::task_active_pid_ns(bindings::get_current()) };
> 
> Why not create a safe wrapper for `bindings::get_current()`?
> This patch series has three occurrences of `get_current`, so I think it
> should be ok to add a wrapper.
> I would also prefer to move the call to `bindings::get_current()` out of
> the `unsafe` block.

FWIW, we have a current!() macro, we should use it here.

Regards,
Boqun

> 
> > +        // SAFETY: We know that `self.0.get()` is valid by the type invariant.
> 
> What about `namespace`?
> 
> -- 
> Cheers,
> Benno
> 
> > +        unsafe { bindings::task_tgid_nr_ns(self.0.get(), namespace) }
> > +    }