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Tsirkin" To: Jakub Kicinski Cc: linux-kernel@vger.kernel.org, Christian Brauner , Stefano Garzarella , Luigi Leonardi , Jason Wang , Xuan Zhuo , Eugenio =?iso-8859-1?Q?P=E9rez?= , Stefan Hajnoczi , "David S. Miller" , Eric Dumazet , Paolo Abeni , Marco Pinna , virtualization@lists.linux.dev, kvm@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH] vsock/virtio: use GFP_ATOMIC under RCU read lock Message-ID: <20241007114637-mutt-send-email-mst@kernel.org> References: <3fbfb6e871f625f89eb578c7228e127437b1975a.1727876449.git.mst@redhat.com> <20241007083920.185578a7@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241007083920.185578a7@kernel.org> On Mon, Oct 07, 2024 at 08:39:20AM -0700, Jakub Kicinski wrote: > On Wed, 2 Oct 2024 09:41:42 -0400 Michael S. Tsirkin wrote: > > virtio_transport_send_pkt in now called on transport fast path, > > under RCU read lock. In that case, we have a bug: virtio_add_sgs > > is called with GFP_KERNEL, and might sleep. > > > > Pass the gfp flags as an argument, and use GFP_ATOMIC on > > the fast path. > > Hi Michael! The To: linux-kernel@vger.kernel.org doesn't give much info > on who you expect to apply this ;) Please let us know if you plan to > take it via your own tree, otherwise we'll ship it to Linus on Thu. Hi! It's in my tree, was in the process of sending a pull request actually.