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, 56 insertions, 0 deletions

diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
new file mode 100644
index 000000000..45ad17062
--- /dev/null
+++ b/drivers/reset/Makefile
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-y += core.o
+obj-y += amlogic/
+obj-y += hisilicon/
+obj-y += spacemit/
+obj-y += starfive/
+obj-y += sti/
+obj-y += tegra/
+obj-$(CONFIG_RESET_A10SR) += reset-a10sr.o
+obj-$(CONFIG_RESET_ASPEED) += reset-aspeed.o
+obj-$(CONFIG_RESET_ATH79) += reset-ath79.o
+obj-$(CONFIG_RESET_AXS10X) += reset-axs10x.o
+obj-$(CONFIG_RESET_BCM6345) += reset-bcm6345.o
+obj-$(CONFIG_RESET_BERLIN) += reset-berlin.o
+obj-$(CONFIG_RESET_BRCMSTB) += reset-brcmstb.o
+obj-$(CONFIG_RESET_BRCMSTB_RESCAL) += reset-brcmstb-rescal.o
+obj-$(CONFIG_RESET_EIC7700) += reset-eic7700.o
+obj-$(CONFIG_RESET_EIC7700_HSP) += reset-eic7700-hsp.o
+obj-$(CONFIG_RESET_EYEQ) += reset-eyeq.o
+obj-$(CONFIG_RESET_GPIO) += reset-gpio.o
+obj-$(CONFIG_RESET_HSDK) += reset-hsdk.o
+obj-$(CONFIG_RESET_IMX_SCU) += reset-imx-scu.o
+obj-$(CONFIG_RESET_IMX7) += reset-imx7.o
+obj-$(CONFIG_RESET_IMX8MP_AUDIOMIX) += reset-imx8mp-audiomix.o
+obj-$(CONFIG_RESET_INTEL_GW) += reset-intel-gw.o
+obj-$(CONFIG_RESET_K210) += reset-k210.o
+obj-$(CONFIG_RESET_K230) += reset-k230.o
+obj-$(CONFIG_RESET_LANTIQ) += reset-lantiq.o
+obj-$(CONFIG_RESET_LPC18XX) += reset-lpc18xx.o
+obj-$(CONFIG_RESET_MCHP_SPARX5) += reset-microchip-sparx5.o
+obj-$(CONFIG_RESET_NPCM) += reset-npcm.o
+obj-$(CONFIG_RESET_NUVOTON_MA35D1) += reset-ma35d1.o
+obj-$(CONFIG_RESET_PISTACHIO) += reset-pistachio.o
+obj-$(CONFIG_RESET_POLARFIRE_SOC) += reset-mpfs.o
+obj-$(CONFIG_RESET_QCOM_AOSS) += reset-qcom-aoss.o
+obj-$(CONFIG_RESET_QCOM_PDC) += reset-qcom-pdc.o
+obj-$(CONFIG_RESET_RASPBERRYPI) += reset-raspberrypi.o
+obj-$(CONFIG_RESET_RZG2L_USBPHY_CTRL) += reset-rzg2l-usbphy-ctrl.o
+obj-$(CONFIG_RESET_RZV2H_USB2PHY) += reset-rzv2h-usb2phy.o
+obj-$(CONFIG_RESET_SCMI) += reset-scmi.o
+obj-$(CONFIG_RESET_SIMPLE) += reset-simple.o
+obj-$(CONFIG_RESET_SKY1) += reset-sky1.o
+obj-$(CONFIG_RESET_SKY1_AUDSS) += reset-sky1-audss.o
+obj-$(CONFIG_RESET_SOCFPGA) += reset-socfpga.o
+obj-$(CONFIG_RESET_SUNPLUS) += reset-sunplus.o
+obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o
+obj-$(CONFIG_RESET_TENSTORRENT_ATLANTIS) += reset-tenstorrent-atlantis.o
+obj-$(CONFIG_RESET_TH1520) += reset-th1520.o
+obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o
+obj-$(CONFIG_RESET_TI_SYSCON) += reset-ti-syscon.o
+obj-$(CONFIG_RESET_TI_TPS380X) += reset-tps380x.o
+obj-$(CONFIG_RESET_TN48M_CPLD) += reset-tn48m.o
+obj-$(CONFIG_RESET_UNIPHIER) += reset-uniphier.o
+obj-$(CONFIG_RESET_UNIPHIER_GLUE) += reset-uniphier-glue.o
+obj-$(CONFIG_RESET_ZYNQ) += reset-zynq.o
+obj-$(CONFIG_RESET_ZYNQMP) += reset-zynqmp.o