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, 31 insertions, 0 deletions

diff --git a/drivers/char/ipmi/Makefile b/drivers/char/ipmi/Makefile
new file mode 100644
index 000000000..4ea450a82
--- /dev/null
+++ b/drivers/char/ipmi/Makefile
@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the ipmi drivers.
+#
+
+ipmi_si-y := ipmi_si_intf.o ipmi_kcs_sm.o ipmi_smic_sm.o ipmi_bt_sm.o \
+	ipmi_si_hotmod.o ipmi_si_hardcode.o ipmi_si_platform.o \
+	ipmi_si_mem_io.o
+ipmi_si-$(CONFIG_HAS_IOPORT) += ipmi_si_port_io.o
+ipmi_si-$(CONFIG_PCI) += ipmi_si_pci.o
+ipmi_si-$(CONFIG_IPMI_LS2K) += ipmi_si_ls2k.o
+ipmi_si-$(CONFIG_PARISC) += ipmi_si_parisc.o
+
+obj-$(CONFIG_IPMI_HANDLER) += ipmi_msghandler.o
+obj-$(CONFIG_IPMI_DEVICE_INTERFACE) += ipmi_devintf.o
+obj-$(CONFIG_IPMI_SI) += ipmi_si.o
+obj-$(CONFIG_IPMI_DMI_DECODE) += ipmi_dmi.o
+obj-$(CONFIG_IPMI_PLAT_DATA) += ipmi_plat_data.o
+obj-$(CONFIG_IPMI_SSIF) += ipmi_ssif.o
+obj-$(CONFIG_IPMI_IPMB) += ipmi_ipmb.o
+obj-$(CONFIG_IPMI_POWERNV) += ipmi_powernv.o
+obj-$(CONFIG_IPMI_WATCHDOG) += ipmi_watchdog.o
+obj-$(CONFIG_IPMI_POWEROFF) += ipmi_poweroff.o
+obj-$(CONFIG_IPMI_KCS_BMC) += kcs_bmc.o
+obj-$(CONFIG_IPMI_KCS_BMC_SERIO) += kcs_bmc_serio.o
+obj-$(CONFIG_IPMI_KCS_BMC_CDEV_IPMI) += kcs_bmc_cdev_ipmi.o
+obj-$(CONFIG_ASPEED_BT_IPMI_BMC) += bt-bmc.o
+obj-$(CONFIG_ASPEED_KCS_IPMI_BMC) += kcs_bmc_aspeed.o
+obj-$(CONFIG_NPCM7XX_KCS_IPMI_BMC) += kcs_bmc_npcm7xx.o
+obj-$(CONFIG_IPMB_DEVICE_INTERFACE) += ipmb_dev_int.o
+obj-$(CONFIG_SSIF_IPMI_BMC) += ssif_bmc.o