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Howlett" , Andrew Morton , Greg Kroah-Hartman , Arnd Bergmann , Christian Brauner , Jann Horn , Suren Baghdasaryan Cc: Alex Gaynor , Boqun Feng , Gary Guo , =?UTF-8?Q?Bj=C3=B6rn_Roy_Baron?= , Benno Lossin , linux-kernel@vger.kernel.org, linux-mm@kvack.org, rust-for-linux@vger.kernel.org, Andreas Hindborg Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 5113A180019 X-Stat-Signature: udt7n4r6y6u44n4hsxj1tkwd73hkf7eo X-Rspam-User: X-HE-Tag: 1732290813-798704 X-HE-Meta: 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 BobDFrO5 dmZzoB40soI6xlINA1tgaEbYIMpMpZsSfef/RY9q4WZV3SRm6KpFECwDSLewj6sZZjvXYnj7yj8lXZ2IG0utyGkGTUfoQLqeOmrQppG9VpbO8S9AkQe/eWKJjuVCclCchVRj0Yt2Npk+ubancL7iOZdXlIzjO+pmVOgxRxwRnuVgIgnU9CyiqWvEGzdUyojw0qLY2WanuEw+D7PCJRSaMLk4JLJLI3bjRyttE/ewWyVQGCUtYaJ96cby8ZZVPO8c7xSclc+iOhMAo3Z8iqSpjRMG2mHg/sv4FhhOSVdc2N1UwzNwsHAmVOLW+mg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000002, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Nov 22, 2024 at 4:41=E2=80=AFPM Alice Ryhl w= rote: > > Introduce a new type called `CurrentTask` that lets you perform various > operations that are only safe on the `current` task. Use the new type to > provide a way to access the current mm without incrementing its > refcount. > > With this change, you can write stuff such as > > let vma =3D current!().mm().lock_vma_under_rcu(addr); > > without incrementing any refcounts. > > Signed-off-by: Alice Ryhl Oh, that's awkward, I was testing this change using a config file that was missing CONFIG_RUST=3Dy, so it didn't compile the code at all. You need the following imports for this to work: diff --git a/rust/kernel/task.rs b/rust/kernel/task.rs index 103d235eb844..60659076997a 100644 --- a/rust/kernel/task.rs +++ b/rust/kernel/task.rs @@ -7,7 +7,8 @@ use crate::{ bindings, ffi::{c_int, c_long, c_uint}, - types::{NotThreadSafe, Opaque}, + mm::MmWithUser, + types::Opaque, }; use core::{ cmp::{Eq, PartialEq}, Otherwise the code should be correct. You can fetch the tree with this fixe= d at: https://github.com/Darksonn/linux/commits/b4/vma/ I'll fix it in the next version, but I will wait for review before I send t= hat. Alice