git: 050f5a8405c6 - main - amd64: Reload CPU ext features after resume or cr4 changes

The branch main has been updated by dchagin:

URL: https://cgit.FreeBSD.org/src/commit/?id=050f5a8405c63dadaf522d27c3d4f2a2ae522bf6

commit 050f5a8405c63dadaf522d27c3d4f2a2ae522bf6
Author:     Dmitry Chagin <dchagin@FreeBSD.org>
AuthorDate: 2022-06-29 07:34:43 +0000
Commit:     Dmitry Chagin <dchagin@FreeBSD.org>
CommitDate: 2022-06-29 07:34:43 +0000

    amd64: Reload CPU ext features after resume or cr4 changes
    
    Reviewed by:            kib
    Differential revision:  https://reviews.freebsd.org/D35555
    MFC after:              2 weeks
---
 sys/amd64/amd64/initcpu.c |  3 +++
 sys/x86/include/x86_var.h |  1 +
 sys/x86/x86/identcpu.c    | 12 ++++++++++++
 3 files changed, 16 insertions(+)

diff --git a/sys/amd64/amd64/initcpu.c b/sys/amd64/amd64/initcpu.c
index 44a294da205a..1a251208cfd6 100644
--- a/sys/amd64/amd64/initcpu.c
+++ b/sys/amd64/amd64/initcpu.c
@@ -292,6 +292,9 @@ initializecpu(void)
 			cr4 |= CR4_SMAP;
 	}
 	load_cr4(cr4);
+	/* Reload cpu ext features to reflect cr4 changes */
+	if (IS_BSP())
+		identify_cpu_ext_features();
 	if (IS_BSP() && (amd_feature & AMDID_NX) != 0) {
 		msr = rdmsr(MSR_EFER) | EFER_NXE;
 		wrmsr(MSR_EFER, msr);
diff --git a/sys/x86/include/x86_var.h b/sys/x86/include/x86_var.h
index b4a27ca01eaa..3e8e643e1b9c 100644
--- a/sys/x86/include/x86_var.h
+++ b/sys/x86/include/x86_var.h
@@ -128,6 +128,7 @@ void	restore_wp(bool old_wp);
 void	finishidentcpu(void);
 void	identify_cpu1(void);
 void	identify_cpu2(void);
+void	identify_cpu_ext_features(void);
 void	identify_cpu_fixup_bsp(void);
 void	identify_hypervisor(void);
 void	initializecpu(void);
diff --git a/sys/x86/x86/identcpu.c b/sys/x86/x86/identcpu.c
index 4ccbd3da311f..7b2d32d9c7a3 100644
--- a/sys/x86/x86/identcpu.c
+++ b/sys/x86/x86/identcpu.c
@@ -1608,6 +1608,18 @@ identify_cpu2(void)
 	}
 }
 
+void
+identify_cpu_ext_features(void)
+{
+	u_int regs[4];
+
+	if (cpu_high >= 7) {
+		cpuid_count(7, 0, regs);
+		cpu_stdext_feature2 = regs[2];
+		cpu_stdext_feature3 = regs[3];
+	}
+}
+
 void
 identify_cpu_fixup_bsp(void)
 {