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, 58 insertions, 0 deletions

diff --git a/drivers/dma/sh/Kconfig b/drivers/dma/sh/Kconfig
new file mode 100644
index 000000000..a16c7e83b
--- /dev/null
+++ b/drivers/dma/sh/Kconfig
@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# DMA engine configuration for sh
+#
+
+config RENESAS_DMA
+	bool
+	select DMA_ENGINE
+
+#
+# DMA Engine Helpers
+#
+
+config SH_DMAE_BASE
+	bool "Renesas SuperH DMA Engine support"
+	depends on SUPERH || COMPILE_TEST
+	depends on !SUPERH || SH_DMA
+	depends on !SH_DMA_API
+	default SUPERH || SH_DMA
+	select RENESAS_DMA
+	help
+	  Enable support for the Renesas SuperH DMA controllers.
+
+#
+# DMA Controllers
+#
+
+config SH_DMAE
+	tristate "Renesas SuperH DMAC support"
+	depends on SH_DMAE_BASE
+	help
+	  Enable support for the Renesas SuperH DMA controllers.
+
+config RCAR_DMAC
+	tristate "Renesas R-Car Gen{2,3} and RZ/G{1,2} DMA Controller"
+	depends on ARCH_RENESAS || COMPILE_TEST
+	select RENESAS_DMA
+	help
+	  This driver supports the general purpose DMA controller found in the
+	  Renesas R-Car Gen{2,3} and RZ/G{1,2} SoCs.
+
+config RENESAS_USB_DMAC
+	tristate "Renesas USB-DMA Controller"
+	depends on ARCH_RENESAS || COMPILE_TEST
+	select RENESAS_DMA
+	select DMA_VIRTUAL_CHANNELS
+	help
+	  This driver supports the USB-DMA controller found in the Renesas
+	  SoCs.
+
+config RZ_DMAC
+	tristate "Renesas RZ DMA Controller"
+	depends on ARCH_RENESAS || COMPILE_TEST
+	select RENESAS_DMA
+	select DMA_VIRTUAL_CHANNELS
+	help
+	  This driver supports the general purpose DMA controller typically
+	  found in the Renesas RZ SoC variants.