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 --- drivers/firmware/efi/riscv-runtime.c | 159 +++++++++++++++++++++++++++++++++++ 1 file changed, 159 insertions(+) create mode 100644 drivers/firmware/efi/riscv-runtime.c (limited to 'drivers/firmware/efi/riscv-runtime.c') diff --git a/drivers/firmware/efi/riscv-runtime.c b/drivers/firmware/efi/riscv-runtime.c new file mode 100644 index 000000000..60cdf7bf1 --- /dev/null +++ b/drivers/firmware/efi/riscv-runtime.c @@ -0,0 +1,159 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Extensible Firmware Interface + * + * Copyright (C) 2020 Western Digital Corporation or its affiliates. + * + * Based on Extensible Firmware Interface Specification version 2.4 + * Adapted from drivers/firmware/efi/arm-runtime.c + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +static bool __init efi_virtmap_init(void) +{ + efi_memory_desc_t *md; + + efi_mm.pgd = pgd_alloc(&efi_mm); + mm_init_cpumask(&efi_mm); + init_new_context(NULL, &efi_mm); + + for_each_efi_memory_desc(md) { + if (!(md->attribute & EFI_MEMORY_RUNTIME)) + continue; + if (md->virt_addr == U64_MAX) + return false; + + efi_create_mapping(&efi_mm, md); + } + + if (efi_memattr_apply_permissions(&efi_mm, efi_set_mapping_permissions)) + return false; + + return true; +} + +/* + * Enable the UEFI Runtime Services if all prerequisites are in place, i.e., + * non-early mapping of the UEFI system table and virtual mappings for all + * EFI_MEMORY_RUNTIME regions. + */ +static int __init riscv_enable_runtime_services(void) +{ + u64 mapsize; + + if (!efi_enabled(EFI_BOOT)) { + pr_info("EFI services will not be available.\n"); + return 0; + } + + efi_memmap_unmap(); + + mapsize = efi.memmap.desc_size * efi.memmap.nr_map; + + if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) { + pr_err("Failed to remap EFI memory map\n"); + return 0; + } + + if (efi_soft_reserve_enabled()) { + efi_memory_desc_t *md; + + for_each_efi_memory_desc(md) { + u64 md_size = md->num_pages << EFI_PAGE_SHIFT; + struct resource *res; + + if (!(md->attribute & EFI_MEMORY_SP)) + continue; + + res = kzalloc_obj(*res); + if (WARN_ON(!res)) + break; + + res->start = md->phys_addr; + res->end = md->phys_addr + md_size - 1; + res->name = "Soft Reserved"; + res->flags = IORESOURCE_MEM; + res->desc = IORES_DESC_SOFT_RESERVED; + + insert_resource(&iomem_resource, res); + } + } + + if (efi_runtime_disabled()) { + pr_info("EFI runtime services will be disabled.\n"); + return 0; + } + + if (efi_enabled(EFI_RUNTIME_SERVICES)) { + pr_info("EFI runtime services access via paravirt.\n"); + return 0; + } + + pr_info("Remapping and enabling EFI services.\n"); + + if (!efi_virtmap_init()) { + pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n"); + return -ENOMEM; + } + + /* Set up runtime services function pointers */ + efi_native_runtime_setup(); + set_bit(EFI_RUNTIME_SERVICES, &efi.flags); + + return 0; +} +early_initcall(riscv_enable_runtime_services); + +static void efi_virtmap_load(void) +{ + preempt_disable(); + switch_mm(current->active_mm, &efi_mm, NULL); +} + +static void efi_virtmap_unload(void) +{ + switch_mm(&efi_mm, current->active_mm, NULL); + preempt_enable(); +} + +void arch_efi_call_virt_setup(void) +{ + sync_kernel_mappings(efi_mm.pgd); + efi_virtmap_load(); +} + +void arch_efi_call_virt_teardown(void) +{ + efi_virtmap_unload(); +} + +static int __init riscv_dmi_init(void) +{ + /* + * On riscv, DMI depends on UEFI, and dmi_setup() needs to + * be called early because dmi_id_init(), which is an arch_initcall + * itself, depends on dmi_scan_machine() having been called already. + */ + dmi_setup(); + + return 0; +} +core_initcall(riscv_dmi_init); -- cgit v1.3.1