git: f9857ea43a38 - stable/14 - bhyve: fix CPUID L3 Cache Size reporting for AMD/SVM

The branch stable/14 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=f9857ea43a38b74e34ce7f6576ad4e6415413454

commit f9857ea43a38b74e34ce7f6576ad4e6415413454
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2024-12-17 21:09:33 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2025-03-12 00:25:02 +0000

    bhyve: fix CPUID L3 Cache Size reporting for AMD/SVM
    
    PR:     279901
    
    (cherry picked from commit 0698ce429f78f548f7eb3e54476fb312109ddd8b)
---
 sys/amd64/vmm/x86.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/sys/amd64/vmm/x86.c b/sys/amd64/vmm/x86.c
index 7d11346ac842..744e2bfd57db 100644
--- a/sys/amd64/vmm/x86.c
+++ b/sys/amd64/vmm/x86.c
@@ -152,8 +152,6 @@ x86_emulate_cpuid(struct vcpu *vcpu, uint64_t *rax, uint64_t *rbx,
 				 * pkg_id_shift and other OSes may rely on it.
 				 */
 				width = MIN(0xF, log2(threads * cores));
-				if (width < 0x4)
-					width = 0;
 				logical_cpus = MIN(0xFF, threads * cores - 1);
 				regs[2] = (width << AMDID_COREID_SIZE_SHIFT) | logical_cpus;
 			}
@@ -258,7 +256,7 @@ x86_emulate_cpuid(struct vcpu *vcpu, uint64_t *rax, uint64_t *rbx,
 				func = 3;	/* unified cache */
 				break;
 			default:
-				logical_cpus = 0;
+				logical_cpus = sockets * threads * cores;
 				level = 0;
 				func = 0;
 				break;
@@ -268,7 +266,14 @@ x86_emulate_cpuid(struct vcpu *vcpu, uint64_t *rax, uint64_t *rbx,
 			regs[0] = (logical_cpus << 14) | (1 << 8) |
 			    (level << 5) | func;
 			regs[1] = (func > 0) ? (CACHE_LINE_SIZE - 1) : 0;
+
+			/*
+			 * ecx: Number of cache ways for non-fully
+			 * associative cache, minus 1.  Reported value
+			 * of zero means there is one way.
+			 */
 			regs[2] = 0;
+
 			regs[3] = 0;
 			break;