From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
Jiri Kosina <jkosina@suse.cz>,
Josh Poimboeuf <jpoimboe@redhat.com>
Subject: [PATCH 4.18 48/79] x86/l1tf: Handle EPT disabled state proper
Date: Tue, 14 Aug 2018 19:17:07 +0200 [thread overview]
Message-ID: <20180814171338.944469263@linuxfoundation.org> (raw)
In-Reply-To: <20180814171336.799314117@linuxfoundation.org>
4.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Thomas Gleixner <tglx@linutronix.de>
If Extended Page Tables (EPT) are disabled or not supported, no L1D
flushing is required. The setup function can just avoid setting up the L1D
flush for the EPT=n case.
Invoke it after the hardware setup has be done and enable_ept has the
correct state and expose the EPT disabled state in the mitigation status as
well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20180713142322.612160168@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/include/asm/vmx.h | 1
arch/x86/kernel/cpu/bugs.c | 9 ++--
arch/x86/kvm/vmx.c | 89 ++++++++++++++++++++++++---------------------
3 files changed, 54 insertions(+), 45 deletions(-)
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -581,6 +581,7 @@ enum vmx_l1d_flush_state {
VMENTER_L1D_FLUSH_NEVER,
VMENTER_L1D_FLUSH_COND,
VMENTER_L1D_FLUSH_ALWAYS,
+ VMENTER_L1D_FLUSH_EPT_DISABLED,
};
extern enum vmx_l1d_flush_state l1tf_vmx_mitigation;
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -676,10 +676,11 @@ static void __init l1tf_select_mitigatio
#if IS_ENABLED(CONFIG_KVM_INTEL)
static const char *l1tf_vmx_states[] = {
- [VMENTER_L1D_FLUSH_AUTO] = "auto",
- [VMENTER_L1D_FLUSH_NEVER] = "vulnerable",
- [VMENTER_L1D_FLUSH_COND] = "conditional cache flushes",
- [VMENTER_L1D_FLUSH_ALWAYS] = "cache flushes",
+ [VMENTER_L1D_FLUSH_AUTO] = "auto",
+ [VMENTER_L1D_FLUSH_NEVER] = "vulnerable",
+ [VMENTER_L1D_FLUSH_COND] = "conditional cache flushes",
+ [VMENTER_L1D_FLUSH_ALWAYS] = "cache flushes",
+ [VMENTER_L1D_FLUSH_EPT_DISABLED] = "EPT disabled",
};
static ssize_t l1tf_show_state(char *buf)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -13292,6 +13292,11 @@ static int __init vmx_setup_l1d_flush(vo
if (!boot_cpu_has_bug(X86_BUG_L1TF))
return 0;
+ if (!enable_ept) {
+ l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_EPT_DISABLED;
+ return 0;
+ }
+
l1tf_vmx_mitigation = vmentry_l1d_flush;
if (vmentry_l1d_flush == VMENTER_L1D_FLUSH_NEVER)
@@ -13318,6 +13323,41 @@ static void vmx_cleanup_l1d_flush(void)
l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_AUTO;
}
+static void vmx_exit(void)
+{
+#ifdef CONFIG_KEXEC_CORE
+ RCU_INIT_POINTER(crash_vmclear_loaded_vmcss, NULL);
+ synchronize_rcu();
+#endif
+
+ kvm_exit();
+
+#if IS_ENABLED(CONFIG_HYPERV)
+ if (static_branch_unlikely(&enable_evmcs)) {
+ int cpu;
+ struct hv_vp_assist_page *vp_ap;
+ /*
+ * Reset everything to support using non-enlightened VMCS
+ * access later (e.g. when we reload the module with
+ * enlightened_vmcs=0)
+ */
+ for_each_online_cpu(cpu) {
+ vp_ap = hv_get_vp_assist_page(cpu);
+
+ if (!vp_ap)
+ continue;
+
+ vp_ap->current_nested_vmcs = 0;
+ vp_ap->enlighten_vmentry = 0;
+ }
+
+ static_branch_disable(&enable_evmcs);
+ }
+#endif
+ vmx_cleanup_l1d_flush();
+}
+module_exit(vmx_exit);
+
static int __init vmx_init(void)
{
int r;
@@ -13351,14 +13391,17 @@ static int __init vmx_init(void)
}
#endif
- r = vmx_setup_l1d_flush();
+ r = kvm_init(&vmx_x86_ops, sizeof(struct vcpu_vmx),
+ __alignof__(struct vcpu_vmx), THIS_MODULE);
if (r)
return r;
- r = kvm_init(&vmx_x86_ops, sizeof(struct vcpu_vmx),
- __alignof__(struct vcpu_vmx), THIS_MODULE);
+ /*
+ * Must be called after kvm_init() so enable_ept is properly set up
+ */
+ r = vmx_setup_l1d_flush();
if (r) {
- vmx_cleanup_l1d_flush();
+ vmx_exit();
return r;
}
@@ -13370,40 +13413,4 @@ static int __init vmx_init(void)
return 0;
}
-
-static void __exit vmx_exit(void)
-{
-#ifdef CONFIG_KEXEC_CORE
- RCU_INIT_POINTER(crash_vmclear_loaded_vmcss, NULL);
- synchronize_rcu();
-#endif
-
- kvm_exit();
-
-#if IS_ENABLED(CONFIG_HYPERV)
- if (static_branch_unlikely(&enable_evmcs)) {
- int cpu;
- struct hv_vp_assist_page *vp_ap;
- /*
- * Reset everything to support using non-enlightened VMCS
- * access later (e.g. when we reload the module with
- * enlightened_vmcs=0)
- */
- for_each_online_cpu(cpu) {
- vp_ap = hv_get_vp_assist_page(cpu);
-
- if (!vp_ap)
- continue;
-
- vp_ap->current_nested_vmcs = 0;
- vp_ap->enlighten_vmentry = 0;
- }
-
- static_branch_disable(&enable_evmcs);
- }
-#endif
- vmx_cleanup_l1d_flush();
-}
-
-module_init(vmx_init)
-module_exit(vmx_exit)
+module_init(vmx_init);
next prev parent reply other threads:[~2018-08-14 17:26 UTC|newest]
Thread overview: 83+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-08-14 17:16 [PATCH 4.18 00/79] 4.18.1-stable review Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 01/79] x86/paravirt: Fix spectre-v2 mitigations for paravirt guests Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 02/79] x86/speculation: Protect against userspace-userspace spectreRSB Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 03/79] kprobes/x86: Fix %p uses in error messages Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 04/79] x86/irqflags: Provide a declaration for native_save_fl Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 05/79] x86/speculation/l1tf: Increase 32bit PAE __PHYSICAL_PAGE_SHIFT Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 06/79] x86/speculation/l1tf: Change order of offset/type in swap entry Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 07/79] x86/speculation/l1tf: Protect swap entries against L1TF Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 08/79] x86/speculation/l1tf: Protect PROT_NONE PTEs against speculation Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 09/79] x86/speculation/l1tf: Make sure the first page is always reserved Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 10/79] x86/speculation/l1tf: Add sysfs reporting for l1tf Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 11/79] x86/speculation/l1tf: Disallow non privileged high MMIO PROT_NONE mappings Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 12/79] x86/speculation/l1tf: Limit swap file size to MAX_PA/2 Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 13/79] x86/bugs: Move the l1tf function and define pr_fmt properly Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 14/79] sched/smt: Update sched_smt_present at runtime Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 15/79] x86/smp: Provide topology_is_primary_thread() Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 16/79] x86/topology: Provide topology_smt_supported() Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 17/79] cpu/hotplug: Make bringup/teardown of smp threads symmetric Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 18/79] cpu/hotplug: Split do_cpu_down() Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 19/79] cpu/hotplug: Provide knobs to control SMT Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 20/79] x86/cpu: Remove the pointless CPU printout Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 21/79] x86/cpu/AMD: Remove the pointless detect_ht() call Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 22/79] x86/cpu/common: Provide detect_ht_early() Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 23/79] x86/cpu/topology: Provide detect_extended_topology_early() Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 24/79] x86/cpu/intel: Evaluate smp_num_siblings early Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 25/79] x86/CPU/AMD: Do not check CPUID max ext level before parsing SMP info Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 26/79] x86/cpu/AMD: Evaluate smp_num_siblings early Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 28/79] x86/speculation/l1tf: Extend 64bit swap file size limit Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 29/79] x86/cpufeatures: Add detection of L1D cache flush support Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 30/79] x86/CPU/AMD: Move TOPOEXT reenablement before reading smp_num_siblings Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 31/79] x86/speculation/l1tf: Protect PAE swap entries against L1TF Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 32/79] x86/speculation/l1tf: Fix up pte->pfn conversion for PAE Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 33/79] Revert "x86/apic: Ignore secondary threads if nosmt=force" Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 34/79] cpu/hotplug: Boot HT siblings at least once Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 35/79] x86/KVM: Warn user if KVM is loaded SMT and L1TF CPU bug being present Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 36/79] x86/KVM/VMX: Add module argument for L1TF mitigation Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 37/79] x86/KVM/VMX: Add L1D flush algorithm Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 38/79] x86/KVM/VMX: Add L1D MSR based flush Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 39/79] x86/KVM/VMX: Add L1D flush logic Greg Kroah-Hartman
2018-08-14 17:16 ` [PATCH 4.18 40/79] x86/KVM/VMX: Split the VMX MSR LOAD structures to have an host/guest numbers Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 41/79] x86/KVM/VMX: Add find_msr() helper function Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 42/79] x86/KVM/VMX: Separate the VMX AUTOLOAD guest/host number accounting Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 43/79] x86/KVM/VMX: Extend add_atomic_switch_msr() to allow VMENTER only MSRs Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 44/79] x86/KVM/VMX: Use MSR save list for IA32_FLUSH_CMD if required Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 45/79] cpu/hotplug: Online siblings when SMT control is turned on Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 46/79] x86/litf: Introduce vmx status variable Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 47/79] x86/kvm: Drop L1TF MSR list approach Greg Kroah-Hartman
2018-08-14 17:17 ` Greg Kroah-Hartman [this message]
2018-08-14 17:17 ` [PATCH 4.18 49/79] x86/kvm: Move l1tf setup function Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 50/79] x86/kvm: Add static key for flush always Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 51/79] x86/kvm: Serialize L1D flush parameter setter Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 52/79] x86/kvm: Allow runtime control of L1D flush Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 53/79] cpu/hotplug: Expose SMT control init function Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 54/79] cpu/hotplug: Set CPU_SMT_NOT_SUPPORTED early Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 55/79] x86/bugs, kvm: Introduce boot-time control of L1TF mitigations Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 56/79] Documentation: Add section about CPU vulnerabilities Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 57/79] x86/speculation/l1tf: Unbreak !__HAVE_ARCH_PFN_MODIFY_ALLOWED architectures Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 58/79] x86/KVM/VMX: Initialize the vmx_l1d_flush_pages content Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 59/79] Documentation/l1tf: Fix typos Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 60/79] cpu/hotplug: detect SMT disabled by BIOS Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 61/79] x86/KVM/VMX: Dont set l1tf_flush_l1d to true from vmx_l1d_flush() Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 62/79] x86/KVM/VMX: Replace vmx_l1d_flush_always with vmx_l1d_flush_cond Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 63/79] x86/KVM/VMX: Move the l1tf_flush_l1d test to vmx_l1d_flush() Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 64/79] x86/irq: Demote irq_cpustat_t::__softirq_pending to u16 Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 65/79] x86/KVM/VMX: Introduce per-host-cpu analogue of l1tf_flush_l1d Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 66/79] x86: Dont include linux/irq.h from asm/hardirq.h Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 67/79] x86/irq: Let interrupt handlers set kvm_cpu_l1tf_flush_l1d Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 68/79] x86/KVM/VMX: Dont set l1tf_flush_l1d from vmx_handle_external_intr() Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 69/79] Documentation/l1tf: Remove Yonah processors from not vulnerable list Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 70/79] x86/speculation: Simplify sysfs report of VMX L1TF vulnerability Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 71/79] x86/speculation: Use ARCH_CAPABILITIES to skip L1D flush on vmentry Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 72/79] KVM: VMX: Tell the nested hypervisor " Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 73/79] cpu/hotplug: Fix SMT supported evaluation Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 74/79] x86/speculation/l1tf: Invert all not present mappings Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 75/79] x86/speculation/l1tf: Make pmd/pud_mknotpresent() invert Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 76/79] x86/mm/pat: Make set_memory_np() L1TF safe Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 77/79] x86/mm/kmmio: Make the tracer robust against L1TF Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 78/79] tools headers: Synchronise x86 cpufeatures.h for L1TF additions Greg Kroah-Hartman
2018-08-14 17:17 ` [PATCH 4.18 79/79] x86/microcode: Allow late microcode loading with SMT disabled Greg Kroah-Hartman
2018-08-15 6:12 ` [PATCH 4.18 00/79] 4.18.1-stable review Greg Kroah-Hartman
2018-08-15 13:16 ` Guenter Roeck
2018-08-15 15:32 ` Greg Kroah-Hartman
2018-08-15 20:12 ` Dan Rue
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