Re: [PATCH v2 01/10] PCI/LUO: Register with Liveupdate Orchestrator

Greg Kroah-Hartman
2025-09-30T15:30:48Z

On Tue, Sep 16, 2025 at 12:45:09AM -0700, Chris Li wrote:
> Register PCI subsystem with the Liveupdate Orchestrator
> and provide noop liveupdate callbacks.
>
> Signed-off-by: Chris Li <chrisl@kernel.org>
> ---
> MAINTAINERS | 2 ++
> drivers/pci/Makefile | 1 +
> drivers/pci/liveupdate.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 57 insertions(+)
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 91cec3288cc81aea199f730924eee1f5fda1fd72..85749a5da69f88544ccc749e9d723b1b54c0e3b7 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -14014,11 +14014,13 @@ F: tools/testing/selftests/livepatch/
>
> LIVE UPDATE
> M: Pasha Tatashin <pasha.tatashin@soleen.com>
> +M: Chris Li <chrisl@kernel.org>
> L: linux-kernel@vger.kernel.org
> S: Maintained
> F: Documentation/ABI/testing/sysfs-kernel-liveupdate
> F: Documentation/admin-guide/liveupdate.rst
> F: drivers/misc/liveupdate/
> +F: drivers/pci/liveupdate/
> F: include/linux/liveupdate.h
> F: include/uapi/linux/liveupdate.h
> F: tools/testing/selftests/liveupdate/
> diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
> index 67647f1880fb8fb0629d680398f5b88d69aac660..aa1bac7aed7d12c641a6b55e56176fb3cdde4c91 100644
> --- a/drivers/pci/Makefile
> +++ b/drivers/pci/Makefile
> @@ -37,6 +37,7 @@ obj-$(CONFIG_PCI_DOE) += doe.o
> obj-$(CONFIG_PCI_DYNAMIC_OF_NODES) += of_property.o
> obj-$(CONFIG_PCI_NPEM) += npem.o
> obj-$(CONFIG_PCIE_TPH) += tph.o
> +obj-$(CONFIG_LIVEUPDATE) += liveupdate.o
>
> # Endpoint library must be initialized before its users
> obj-$(CONFIG_PCI_ENDPOINT) += endpoint/
> diff --git a/drivers/pci/liveupdate.c b/drivers/pci/liveupdate.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..86b4f3a2fb44781c6e323ba029db510450556fa9
> --- /dev/null
> +++ b/drivers/pci/liveupdate.c
> @@ -0,0 +1,54 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +/*
> + * Copyright (c) 2025, Google LLC.
> + * Chris Li <chrisl@kernel.org>
> + */
> +
> +#define pr_fmt(fmt) "PCI liveupdate: " fmt
> +
> +#include <linux/liveupdate.h>
> +
> +#define PCI_SUBSYSTEM_NAME "pci"
> +
> +static int pci_liveupdate_prepare(void *arg, u64 *data)
> +{
> + pr_info("prepare data[%llx]\n", *data);

You do know that's a security bug, right?

Please don't do this, even in "debug" code, as it can escape into the
wild...

thanks,

greg k-h