From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Vitaly Kuznetsov <vkuznets@redhat.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Subject: [PATCH 5.4 74/78] x86/kvm: Disable all PV features on crash
Date: Tue, 8 Jun 2021 20:27:43 +0200 [thread overview]
Message-ID: <20210608175937.760953542@linuxfoundation.org> (raw)
In-Reply-To: <20210608175935.254388043@linuxfoundation.org>
From: Vitaly Kuznetsov <vkuznets@redhat.com>
commit 3d6b84132d2a57b5a74100f6923a8feb679ac2ce upstream.
Crash shutdown handler only disables kvmclock and steal time, other PV
features remain active so we risk corrupting memory or getting some
side-effects in kdump kernel. Move crash handler to kvm.c and unify
with CPU offline.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210414123544.1060604-5-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/include/asm/kvm_para.h | 6 -----
arch/x86/kernel/kvm.c | 44 +++++++++++++++++++++++++++++-----------
arch/x86/kernel/kvmclock.c | 21 -------------------
3 files changed, 32 insertions(+), 39 deletions(-)
--- a/arch/x86/include/asm/kvm_para.h
+++ b/arch/x86/include/asm/kvm_para.h
@@ -91,7 +91,6 @@ unsigned int kvm_arch_para_hints(void);
void kvm_async_pf_task_wait(u32 token, int interrupt_kernel);
void kvm_async_pf_task_wake(u32 token);
u32 kvm_read_and_reset_pf_reason(void);
-extern void kvm_disable_steal_time(void);
void do_async_page_fault(struct pt_regs *regs, unsigned long error_code, unsigned long address);
#ifdef CONFIG_PARAVIRT_SPINLOCKS
@@ -125,11 +124,6 @@ static inline u32 kvm_read_and_reset_pf_
{
return 0;
}
-
-static inline void kvm_disable_steal_time(void)
-{
- return;
-}
#endif
#endif /* _ASM_X86_KVM_PARA_H */
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -34,6 +34,7 @@
#include <asm/apicdef.h>
#include <asm/hypervisor.h>
#include <asm/tlb.h>
+#include <asm/reboot.h>
static int kvmapf = 1;
@@ -352,6 +353,14 @@ static void kvm_pv_disable_apf(void)
smp_processor_id());
}
+static void kvm_disable_steal_time(void)
+{
+ if (!has_steal_clock)
+ return;
+
+ wrmsr(MSR_KVM_STEAL_TIME, 0, 0);
+}
+
static void kvm_pv_guest_cpu_reboot(void *unused)
{
/*
@@ -394,14 +403,6 @@ static u64 kvm_steal_clock(int cpu)
return steal;
}
-void kvm_disable_steal_time(void)
-{
- if (!has_steal_clock)
- return;
-
- wrmsr(MSR_KVM_STEAL_TIME, 0, 0);
-}
-
static inline void __set_percpu_decrypted(void *ptr, unsigned long size)
{
early_set_memory_decrypted((unsigned long) ptr, size);
@@ -429,13 +430,14 @@ static void __init sev_map_percpu_data(v
}
}
-static void kvm_guest_cpu_offline(void)
+static void kvm_guest_cpu_offline(bool shutdown)
{
kvm_disable_steal_time();
if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
wrmsrl(MSR_KVM_PV_EOI_EN, 0);
kvm_pv_disable_apf();
- apf_task_wake_all();
+ if (!shutdown)
+ apf_task_wake_all();
kvmclock_disable();
}
@@ -573,7 +575,7 @@ static int kvm_cpu_down_prepare(unsigned
unsigned long flags;
local_irq_save(flags);
- kvm_guest_cpu_offline();
+ kvm_guest_cpu_offline(false);
local_irq_restore(flags);
return 0;
}
@@ -582,7 +584,7 @@ static int kvm_cpu_down_prepare(unsigned
static int kvm_suspend(void)
{
- kvm_guest_cpu_offline();
+ kvm_guest_cpu_offline(false);
return 0;
}
@@ -597,6 +599,20 @@ static struct syscore_ops kvm_syscore_op
.resume = kvm_resume,
};
+/*
+ * After a PV feature is registered, the host will keep writing to the
+ * registered memory location. If the guest happens to shutdown, this memory
+ * won't be valid. In cases like kexec, in which you install a new kernel, this
+ * means a random memory location will be kept being written.
+ */
+#ifdef CONFIG_KEXEC_CORE
+static void kvm_crash_shutdown(struct pt_regs *regs)
+{
+ kvm_guest_cpu_offline(true);
+ native_machine_crash_shutdown(regs);
+}
+#endif
+
static void __init kvm_apf_trap_init(void)
{
update_intr_gate(X86_TRAP_PF, async_page_fault);
@@ -673,6 +689,10 @@ static void __init kvm_guest_init(void)
kvm_guest_cpu_init();
#endif
+#ifdef CONFIG_KEXEC_CORE
+ machine_ops.crash_shutdown = kvm_crash_shutdown;
+#endif
+
register_syscore_ops(&kvm_syscore_ops);
/*
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -20,7 +20,6 @@
#include <asm/hypervisor.h>
#include <asm/mem_encrypt.h>
#include <asm/x86_init.h>
-#include <asm/reboot.h>
#include <asm/kvmclock.h>
static int kvmclock __initdata = 1;
@@ -197,23 +196,6 @@ static void kvm_setup_secondary_clock(vo
}
#endif
-/*
- * After the clock is registered, the host will keep writing to the
- * registered memory location. If the guest happens to shutdown, this memory
- * won't be valid. In cases like kexec, in which you install a new kernel, this
- * means a random memory location will be kept being written. So before any
- * kind of shutdown from our side, we unregister the clock by writing anything
- * that does not have the 'enable' bit set in the msr
- */
-#ifdef CONFIG_KEXEC_CORE
-static void kvm_crash_shutdown(struct pt_regs *regs)
-{
- native_write_msr(msr_kvm_system_time, 0, 0);
- kvm_disable_steal_time();
- native_machine_crash_shutdown(regs);
-}
-#endif
-
void kvmclock_disable(void)
{
native_write_msr(msr_kvm_system_time, 0, 0);
@@ -344,9 +326,6 @@ void __init kvmclock_init(void)
#endif
x86_platform.save_sched_clock_state = kvm_save_sched_clock_state;
x86_platform.restore_sched_clock_state = kvm_restore_sched_clock_state;
-#ifdef CONFIG_KEXEC_CORE
- machine_ops.crash_shutdown = kvm_crash_shutdown;
-#endif
kvm_get_preset_lpj();
/*
next prev parent reply other threads:[~2021-06-08 18:53 UTC|newest]
Thread overview: 87+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-08 18:26 [PATCH 5.4 00/78] 5.4.125-rc1 review Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 01/78] btrfs: tree-checker: do not error out if extent ref hash doesnt match Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 02/78] net: usb: cdc_ncm: dont spew notifications Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 03/78] ALSA: usb: update old-style static const declaration Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 04/78] nl80211: validate key indexes for cfg80211_registered_device Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 05/78] hwmon: (dell-smm-hwmon) Fix index values Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 06/78] netfilter: conntrack: unregister ipv4 sockopts on error unwind Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 07/78] efi: Allow EFI_MEMORY_XP and EFI_MEMORY_RO both to be cleared Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 08/78] efi: cper: fix snprintf() use in cper_dimm_err_location() Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 09/78] vfio/pci: Fix error return code in vfio_ecap_init() Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 10/78] vfio/pci: zap_vma_ptes() needs MMU Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 11/78] samples: vfio-mdev: fix error handing in mdpy_fb_probe() Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 12/78] vfio/platform: fix module_put call in error flow Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 13/78] ipvs: ignore IP_VS_SVC_F_HASHED flag when adding service Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 14/78] HID: pidff: fix error return code in hid_pidff_init() Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 15/78] HID: i2c-hid: fix format string mismatch Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 16/78] net/sched: act_ct: Fix ct template allocation for zone 0 Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 17/78] ACPICA: Clean up context mutex during object deletion Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 18/78] netfilter: nft_ct: skip expectations for confirmed conntrack Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 19/78] netfilter: nfnetlink_cthelper: hit EBUSY on updates if size mismatches Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 20/78] ieee802154: fix error return code in ieee802154_add_iface() Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 21/78] ieee802154: fix error return code in ieee802154_llsec_getparams() Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 22/78] ixgbevf: add correct exception tracing for XDP Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 23/78] ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 24/78] ice: write register with correct offset Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 25/78] ice: Fix VFR issues for AVF drivers that expect ATQLEN cleared Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 26/78] ice: Allow all LLDP packets from PF to Tx Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 27/78] i2c: qcom-geni: Add shutdown callback for i2c Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 28/78] i40e: optimize for XDP_REDIRECT in xsk path Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 29/78] i40e: add correct exception tracing for XDP Greg Kroah-Hartman
2021-06-08 18:26 ` [PATCH 5.4 30/78] arm64: dts: ls1028a: fix memory node Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 31/78] arm64: dts: zii-ultra: fix 12V_MAIN voltage Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 32/78] ARM: dts: imx7d-meerkat96: Fix the tuning-step property Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 33/78] ARM: dts: imx7d-pico: " Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 34/78] ARM: dts: imx: emcon-avari: Fix nxp,pca8574 #gpio-cells Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 35/78] bus: ti-sysc: Fix flakey idling of uarts and stop using swsup_sidle_act Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 36/78] tipc: add extack messages for bearer/media failure Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 37/78] tipc: fix unique bearer names sanity check Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 38/78] Bluetooth: fix the erroneous flush_work() order Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 39/78] Bluetooth: use correct lock to prevent UAF of hdev object Greg Kroah-Hartman
2021-06-14 14:15 ` Eric Dumazet
2021-06-16 15:01 ` Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 40/78] net: caif: added cfserl_release function Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 41/78] net: caif: add proper error handling Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 42/78] net: caif: fix memory leak in caif_device_notify Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 43/78] net: caif: fix memory leak in cfusbl_device_notify Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 44/78] HID: i2c-hid: Skip ELAN power-on command after reset Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 45/78] HID: magicmouse: fix NULL-deref on disconnect Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 46/78] HID: multitouch: require Finger field to mark Win8 reports as MT Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 47/78] ALSA: timer: Fix master timer notification Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 48/78] ALSA: hda: Fix for mute key LED for HP Pavilion 15-CK0xx Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 49/78] ARM: dts: imx6dl-yapp4: Fix RGMII connection to QCA8334 switch Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 50/78] ARM: dts: imx6q-dhcom: Add PU,VDD1P1,VDD2P5 regulators Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 51/78] ext4: fix bug on in ext4_es_cache_extent as ext4_split_extent_at failed Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 52/78] usb: dwc2: Fix build in periphal-only mode Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 53/78] pid: take a reference when initializing `cad_pid` Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 54/78] ocfs2: fix data corruption by fallocate Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 55/78] nfc: fix NULL ptr dereference in llcp_sock_getname() after failed connect Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 56/78] drm/amdgpu: Dont query CE and UE errors Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 57/78] drm/amdgpu: make sure we unpin the UVD BO Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 58/78] x86/apic: Mark _all_ legacy interrupts when IO/APIC is missing Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 59/78] btrfs: mark ordered extent and inode with error if we fail to finish Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 60/78] btrfs: fix error handling in btrfs_del_csums Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 61/78] btrfs: return errors from btrfs_del_csums in cleanup_ref_head Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 62/78] btrfs: fixup error handling in fixup_inode_link_counts Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 63/78] mm, hugetlb: fix simple resv_huge_pages underflow on UFFDIO_COPY Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 64/78] bnxt_en: Remove the setting of dev_port Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 65/78] mm: add thp_order Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 66/78] XArray: add xa_get_order Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 67/78] XArray: add xas_split Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 68/78] mm/filemap: fix storing to a THP shadow entry Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 69/78] btrfs: fix unmountable seed device after fstrim Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 70/78] KVM: SVM: Truncate GPR value for DR and CR accesses in !64-bit mode Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 71/78] KVM: arm64: Fix debug register indexing Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 72/78] x86/kvm: Teardown PV features on boot CPU as well Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 73/78] x86/kvm: Disable kvmclock on all CPUs on shutdown Greg Kroah-Hartman
2021-06-08 18:27 ` Greg Kroah-Hartman [this message]
2021-06-08 18:27 ` [PATCH 5.4 75/78] lib/lz4: explicitly support in-place decompression Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 76/78] xen-pciback: redo VF placement in the virtual topology Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 77/78] i2c: qcom-geni: Suspend and resume the bus during SYSTEM_SLEEP_PM ops Greg Kroah-Hartman
2021-06-08 18:27 ` [PATCH 5.4 78/78] neighbour: allow NUD_NOARP entries to be forced GCed Greg Kroah-Hartman
2021-06-09 2:55 ` [PATCH 5.4 00/78] 5.4.125-rc1 review Shuah Khan
2021-06-09 9:33 ` Jon Hunter
2021-06-09 10:15 ` Naresh Kamboju
2021-06-09 18:40 ` Florian Fainelli
2021-06-09 18:49 ` Guenter Roeck
2021-06-10 9:01 ` Sudip Mukherjee
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