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AFNElJ8tuWEVq16ZlWgN8Fvb9ugyRSz+Hy3+xj/NGdt0MjPVyKeGIoq43upq815UatYa/C7ErpWjcD4pU9my@vger.kernel.org X-Gm-Message-State: AOJu0YzyEIzO4CO31fuAK2s+MKeGB7qEiwKgvJL7Qirwy0SkBHPgbXel Oe+fNPq2gbKjrDvPThqeoaGC0ECyMsUZIo4DBowd47BCQnlDFZIziGATr0u3LFYHjqpH7gQfBtW jhTXFw4KGRctZ2eqaXg== X-Received: from wrmd3.prod.google.com ([2002:adf:e883:0:b0:43d:7940:a11b]) (user=aliceryhl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6000:41c7:b0:43d:799c:b2cb with SMTP id ffacd0b85a97d-44636a393e7mr256856f8f.24.1777313249648; Mon, 27 Apr 2026 11:07:29 -0700 (PDT) Date: Mon, 27 Apr 2026 18:07:28 +0000 In-Reply-To: <289b424e243ba2c4139ea04009cf8b9c448a87ff.1777306795.git.chleroy@kernel.org> Precedence: bulk X-Mailing-List: linux-arch@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <289b424e243ba2c4139ea04009cf8b9c448a87ff.1777306795.git.chleroy@kernel.org> Message-ID: Subject: Re: [RFC PATCH v1 5/9] uaccess: Switch to copy_{to/from}_user_partial() when relevant From: Alice Ryhl To: "Christophe Leroy (CS GROUP)" Cc: Yury Norov , Andrew Morton , Linus Torvalds , David Laight , Thomas Gleixner , linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, dmaengine@vger.kernel.org, linux-efi@vger.kernel.org, linux-fsi@lists.ozlabs.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-wpan@vger.kernel.org, netdev@vger.kernel.org, linux-wireless@vger.kernel.org, linux-spi@vger.kernel.org, linux-media@vger.kernel.org, linux-staging@lists.linux.dev, linux-serial@vger.kernel.org, linux-usb@vger.kernel.org, xen-devel@lists.xenproject.org, linux-fsdevel@vger.kernel.org, ocfs2-devel@lists.linux.dev, bpf@vger.kernel.org, kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-x25@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-sound@vger.kernel.org, sound-open-firmware@alsa-project.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, loongarch@lists.linux.dev, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-parisc@vger.kernel.org, linux-sh@vger.kernel.org, linux-arch@vger.kernel.org Content-Type: text/plain; charset="utf-8" On Mon, Apr 27, 2026 at 07:13:46PM +0200, Christophe Leroy (CS GROUP) wrote: > diff --git a/rust/helpers/uaccess.c b/rust/helpers/uaccess.c > index 01de4fbbcc84..710e07cd60ae 100644 > --- a/rust/helpers/uaccess.c > +++ b/rust/helpers/uaccess.c > @@ -5,13 +5,13 @@ > __rust_helper unsigned long > rust_helper_copy_from_user(void *to, const void __user *from, unsigned long n) > { > - return copy_from_user(to, from, n); > + return copy_from_user_partial(to, from, n); > } > > __rust_helper unsigned long > rust_helper_copy_to_user(void __user *to, const void *from, unsigned long n) > { > - return copy_to_user(to, from, n); > + return copy_to_user_partial(to, from, n); > } No Rust code uses the return value for anything other than comparing it with zero, so you can keep these as copy_[from|to]_user() without issues. Thanks, Alice