From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- Documentation/admin-guide/sysctl/xen.rst | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 Documentation/admin-guide/sysctl/xen.rst (limited to 'Documentation/admin-guide/sysctl/xen.rst') diff --git a/Documentation/admin-guide/sysctl/xen.rst b/Documentation/admin-guide/sysctl/xen.rst new file mode 100644 index 000000000..6c5edc3e5 --- /dev/null +++ b/Documentation/admin-guide/sysctl/xen.rst @@ -0,0 +1,31 @@ +=============== +/proc/sys/xen/ +=============== + +Copyright (c) 2026, Shubham Chakraborty + +For general info and legal blurb, please look in +Documentation/admin-guide/sysctl/index.rst. + +------------------------------------------------------------------------------ + +These files show up in ``/proc/sys/xen/``, depending on the +kernel configuration: + +.. contents:: :local: + +balloon/hotplug_unpopulated +=========================== + +This flag controls whether unpopulated memory ranges are automatically +hotplugged as system RAM. + +- ``0``: Unpopulated ranges are not hotplugged (default). +- ``1``: Unpopulated ranges are automatically hotplugged. + +When enabled, the Xen balloon driver will add memory regions that are +marked as unpopulated in the Xen memory map to the system as usable RAM. +This allows for dynamic memory expansion in Xen guest domains. + +This option is only available when the kernel is built with +``CONFIG_XEN_BALLOON_MEMORY_HOTPLUG`` enabled. -- cgit v1.3.1