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Date: Mon, 7 Oct 2024 08:39:20 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: linux-kernel@vger.kernel.org, Christian Brauner <brauner@kernel.org>,
 Stefano Garzarella <sgarzare@redhat.com>, Luigi Leonardi
 <luigi.leonardi@outlook.com>, Jason Wang <jasowang@redhat.com>, Xuan Zhuo
 <xuanzhuo@linux.alibaba.com>, Eugenio =?UTF-8?B?UMOpcmV6?=
 <eperezma@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>, "David S.
 Miller" <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>, Paolo
 Abeni <pabeni@redhat.com>, Marco Pinna <marco.pinn95@gmail.com>,
 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: <20241007083920.185578a7@kernel.org>
In-Reply-To: <3fbfb6e871f625f89eb578c7228e127437b1975a.1727876449.git.mst@redhat.com>
References: <3fbfb6e871f625f89eb578c7228e127437b1975a.1727876449.git.mst@redhat.com>
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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.