x86/amd_node: Fix PCI device reference counting in amd_smn_init()grafted

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 <sashiko-bot@kernel.org>
Assisted-by: LLM
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Cc: <stable@kernel.org>
Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com

1 files changed, 57 insertions, 0 deletions

diff --git a/sound/hda/controllers/Kconfig b/sound/hda/controllers/Kconfig
new file mode 100644
index 000000000..26ca69b09
--- /dev/null
+++ b/sound/hda/controllers/Kconfig
@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config SND_HDA_INTEL
+	tristate "HD Audio PCI"
+	depends on PCI
+	select SND_HDA
+	select SND_INTEL_DSP_CONFIG
+	help
+	  Say Y here to include support for Intel "High Definition
+	  Audio" (Azalia) and its compatible devices.
+
+	  This option enables the HD-audio controller.  Don't forget
+	  to choose the appropriate HD-audio codec options.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-hda-intel.
+
+config SND_HDA_TEGRA
+	tristate "NVIDIA Tegra HD Audio"
+	depends on ARCH_TEGRA
+	select SND_HDA
+	select SND_HDA_ALIGNED_MMIO
+	help
+	  Say Y here to support the HDA controller present in NVIDIA
+	  Tegra SoCs
+
+	  This options enables support for the HD Audio controller
+	  present in some NVIDIA Tegra SoCs, used to communicate audio
+	  to the HDMI output.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-hda-tegra.
+
+config SND_HDA_CIX_IPBLOQ
+	tristate "CIX IPBLOQ HD Audio"
+	depends on ARCH_CIX || COMPILE_TEST
+	depends on ARCH_DMA_ADDR_T_64BIT
+	select SND_HDA
+	select SND_HDA_ALIGNED_MMIO
+	help
+	  Say Y here to support the HDA controller present in CIX SoCs
+
+	  This options enables support for the HD Audio controller
+	  present in some CIX SoCs.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-hda-cix-ipbloq.
+
+config SND_HDA_ACPI
+	tristate "HD Audio ACPI"
+	depends on ACPI
+	select SND_HDA
+	help
+	  Say Y here to include support for Azalia-compatible HDA controllers
+	  which are advertised via ACPI objects.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-hda-acpi.