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

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

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