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 --- include/xen/hvm.h | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 include/xen/hvm.h (limited to 'include/xen/hvm.h') diff --git a/include/xen/hvm.h b/include/xen/hvm.h new file mode 100644 index 000000000..8da7a6747 --- /dev/null +++ b/include/xen/hvm.h @@ -0,0 +1,65 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Simple wrappers around HVM functions */ +#ifndef XEN_HVM_H__ +#define XEN_HVM_H__ + +#include +#include + +static const char *param_name(int op) +{ +#define PARAM(x) [HVM_PARAM_##x] = #x + static const char *const names[] = { + PARAM(CALLBACK_IRQ), + PARAM(STORE_PFN), + PARAM(STORE_EVTCHN), + PARAM(PAE_ENABLED), + PARAM(IOREQ_PFN), + PARAM(BUFIOREQ_PFN), + PARAM(TIMER_MODE), + PARAM(HPET_ENABLED), + PARAM(IDENT_PT), + PARAM(DM_DOMAIN), + PARAM(ACPI_S_STATE), + PARAM(VM86_TSS), + PARAM(VPT_ALIGN), + PARAM(CONSOLE_PFN), + PARAM(CONSOLE_EVTCHN), + }; +#undef PARAM + + if (op >= ARRAY_SIZE(names)) + return "unknown"; + + if (!names[op]) + return "reserved"; + + return names[op]; +} +static inline int hvm_get_parameter(int idx, uint64_t *value) +{ + struct xen_hvm_param xhv; + int r; + + xhv.domid = DOMID_SELF; + xhv.index = idx; + r = HYPERVISOR_hvm_op(HVMOP_get_param, &xhv); + if (r < 0) { + pr_err("Cannot get hvm parameter %s (%d): %d!\n", + param_name(idx), idx, r); + return r; + } + *value = xhv.value; + return r; +} + +#define HVM_CALLBACK_VIA_TYPE_VECTOR 0x2 +#define HVM_CALLBACK_VIA_TYPE_SHIFT 56 +#define HVM_CALLBACK_VECTOR(x) (((uint64_t)HVM_CALLBACK_VIA_TYPE_VECTOR)<<\ + HVM_CALLBACK_VIA_TYPE_SHIFT | (x)) + +void xen_setup_callback_vector(void); + +int xen_set_upcall_vector(unsigned int cpu); + +#endif /* XEN_HVM_H__ */ -- cgit v1.3.1