[tip: x86/misc] x86/amd_nb: Restrict init function to AMD-based systems

[tip-bot2 for Yazen Ghannam]

The following commit has been merged into the x86/misc branch of tip:

Commit-ID:     bee9e840609cc67d0a7d82f22a2130fb7a0a766d
Gitweb:        https://git.kernel.org/tip/bee9e840609cc67d0a7d82f22a2130fb7a0a766d
Author:        Yazen Ghannam <yazen.ghannam@xxxxxxx>
AuthorDate:    Fri, 06 Dec 2024 16:11:55 
Committer:     Borislav Petkov (AMD) <bp@xxxxxxxxx>
CommitterDate: Wed, 08 Jan 2025 10:46:57 +01:00

x86/amd_nb: Restrict init function to AMD-based systems

The code implicitly operates on AMD-based systems by matching on PCI
IDs. However, the use of these IDs is going away.

Add an explicit CPU vendor check instead of relying on PCI IDs.

Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Link: https://lore.kernel.org/r/20241206161210.163701-3-yazen.ghannam@xxxxxxx
---
 arch/x86/kernel/amd_nb.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/x86/kernel/amd_nb.c b/arch/x86/kernel/amd_nb.c
index 9fe9972..37b8244 100644
--- a/arch/x86/kernel/amd_nb.c
+++ b/arch/x86/kernel/amd_nb.c
@@ -582,6 +582,10 @@ static __init void fix_erratum_688(void)
 
 static __init int init_amd_nbs(void)
 {
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
+	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
+		return 0;
+
 	amd_cache_northbridges();
 	amd_cache_gart();