Merge tag 'kvmarm-fixes-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for 6.12, take #1

- Fix pKVM error path on init, making sure we do not change critical
  system registers as we're about to fail

- Make sure that the host's vector length is at capped by a value
  common to all CPUs

- Fix kvm_has_feat*() handling of "negative" features, as the current
  code is pretty broken

- Promote Joey to the status of official reviewer, while James steps
  down -- hopefully only temporarly

1 files changed, 22 insertions, 4 deletions

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index d4e539d4e158..07a34d723505 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1165,8 +1165,8 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
 
 	VULNWL_INTEL(INTEL_CORE_YONAH,		NO_SSB),
 
-	VULNWL_INTEL(INTEL_ATOM_AIRMONT_MID,	NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
-	VULNWL_INTEL(INTEL_ATOM_AIRMONT_NP,	NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT),
+	VULNWL_INTEL(INTEL_ATOM_AIRMONT_MID,	NO_SSB | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT | MSBDS_ONLY),
+	VULNWL_INTEL(INTEL_ATOM_AIRMONT_NP,	NO_SSB | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT),
 
 	VULNWL_INTEL(INTEL_ATOM_GOLDMONT,	NO_MDS | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO),
 	VULNWL_INTEL(INTEL_ATOM_GOLDMONT_D,	NO_MDS | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO),
@@ -1510,6 +1510,11 @@ static void __init cpu_parse_early_param(void)
 	if (cmdline_find_option_bool(boot_command_line, "nousershstk"))
 		setup_clear_cpu_cap(X86_FEATURE_USER_SHSTK);
 
+	/* Minimize the gap between FRED is available and available but disabled. */
+	arglen = cmdline_find_option(boot_command_line, "fred", arg, sizeof(arg));
+	if (arglen != 2 || strncmp(arg, "on", 2))
+		setup_clear_cpu_cap(X86_FEATURE_FRED);
+
 	arglen = cmdline_find_option(boot_command_line, "clearcpuid", arg, sizeof(arg));
 	if (arglen <= 0)
 		return;
@@ -2171,7 +2176,7 @@ static inline void tss_setup_io_bitmap(struct tss_struct *tss)
  * Setup everything needed to handle exceptions from the IDT, including the IST
  * exceptions which use paranoid_entry().
  */
-void cpu_init_exception_handling(void)
+void cpu_init_exception_handling(bool boot_cpu)
 {
 	struct tss_struct *tss = this_cpu_ptr(&cpu_tss_rw);
 	int cpu = raw_smp_processor_id();
@@ -2190,10 +2195,23 @@ void cpu_init_exception_handling(void)
 	/* GHCB needs to be setup to handle #VC. */
 	setup_ghcb();
 
+	if (cpu_feature_enabled(X86_FEATURE_FRED)) {
+		/* The boot CPU has enabled FRED during early boot */
+		if (!boot_cpu)
+			cpu_init_fred_exceptions();
+
+		cpu_init_fred_rsps();
+	} else {
+		load_current_idt();
+	}
+}
+
+void __init cpu_init_replace_early_idt(void)
+{
 	if (cpu_feature_enabled(X86_FEATURE_FRED))
 		cpu_init_fred_exceptions();
 	else
-		load_current_idt();
+		idt_setup_early_pf();
 }
 
 /*