From 8fbe6a541f50eeec5e3e49bd92db23ade9496673 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Wed, 15 Aug 2012 16:00:40 +0200 Subject: KVM guest: disable stealtime on reboot to avoid mem corruption else, host continues to update stealtime after reboot, which can corrupt e.g. initramfs area. found when tracking down initramfs unpack error on initial reboot (with qemu-kvm -smp 2, no problem with single-core). Signed-off-by: Florian Westphal Signed-off-by: Marcelo Tosatti --- arch/x86/kernel/kvm.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/kernel/kvm.c') diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index c1d61ee4b4f1..1596cc8fd793 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -354,6 +354,7 @@ static void kvm_pv_guest_cpu_reboot(void *unused) if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) wrmsrl(MSR_KVM_PV_EOI_EN, 0); kvm_pv_disable_apf(); + kvm_disable_steal_time(); } static int kvm_pv_reboot_notify(struct notifier_block *nb, -- cgit v1.2.3 From 90993cdd1800dc6ef9587431a0c625b978584e81 Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti Date: Thu, 16 Aug 2012 17:00:19 -0300 Subject: x86: KVM guest: merge CONFIG_KVM_CLOCK into CONFIG_KVM_GUEST The distinction between CONFIG_KVM_CLOCK and CONFIG_KVM_GUEST is not so clear anymore, as demonstrated by recent bugs caused by poor handling of on/off combinations of these options. Merge CONFIG_KVM_CLOCK into CONFIG_KVM_GUEST. Reported-By: OGAWA Hirofumi Signed-off-by: Marcelo Tosatti --- arch/x86/Kconfig | 21 ++++++++------------- arch/x86/include/asm/kvm_para.h | 4 ++-- arch/x86/kernel/Makefile | 3 +-- arch/x86/kernel/kvm.c | 2 -- arch/x86/kernel/setup.c | 2 +- 5 files changed, 12 insertions(+), 20 deletions(-) (limited to 'arch/x86/kernel/kvm.c') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 8ec3a1aa4abd..a42e2e99caae 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -573,23 +573,18 @@ config PARAVIRT_TIME_ACCOUNTING source "arch/x86/xen/Kconfig" -config KVM_CLOCK - bool "KVM paravirtualized clock" - select PARAVIRT - select PARAVIRT_CLOCK - ---help--- - Turning on this option will allow you to run a paravirtualized clock - when running over the KVM hypervisor. Instead of relying on a PIT - (or probably other) emulation by the underlying device model, the host - provides the guest with timing infrastructure such as time of day, and - system time - config KVM_GUEST - bool "KVM Guest support" + bool "KVM Guest support (including kvmclock)" + select PARAVIRT select PARAVIRT + select PARAVIRT_CLOCK + default y if PARAVIRT_GUEST ---help--- This option enables various optimizations for running under the KVM - hypervisor. + hypervisor. It includes a paravirtualized clock, so that instead + of relying on a PIT (or probably other) emulation by the + underlying device model, the host provides the guest with + timing infrastructure such as time of day, and system time source "arch/x86/lguest/Kconfig" diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index 20f5697888bd..eb3e9d85e1f1 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -102,14 +102,14 @@ struct kvm_vcpu_pv_apf_data { extern void kvmclock_init(void); extern int kvm_register_clock(char *txt); -#ifdef CONFIG_KVM_CLOCK +#ifdef CONFIG_KVM_GUEST bool kvm_check_and_clear_guest_paused(void); #else static inline bool kvm_check_and_clear_guest_paused(void) { return false; } -#endif /* CONFIG_KVMCLOCK */ +#endif /* CONFIG_KVM_GUEST */ /* This instruction is vmcall. On non-VT architectures, it will generate a * trap that we will then rewrite to the appropriate instruction. diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 8215e5652d97..7203298e0b83 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -81,8 +81,7 @@ obj-$(CONFIG_DEBUG_RODATA_TEST) += test_rodata.o obj-$(CONFIG_DEBUG_NX_TEST) += test_nx.o obj-$(CONFIG_DEBUG_NMI_SELFTEST) += nmi_selftest.o -obj-$(CONFIG_KVM_GUEST) += kvm.o -obj-$(CONFIG_KVM_CLOCK) += kvmclock.o +obj-$(CONFIG_KVM_GUEST) += kvm.o kvmclock.o obj-$(CONFIG_PARAVIRT) += paravirt.o paravirt_patch_$(BITS).o obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= paravirt-spinlocks.o obj-$(CONFIG_PARAVIRT_CLOCK) += pvclock.o diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 1596cc8fd793..b3e5e51bc907 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -397,9 +397,7 @@ void kvm_disable_steal_time(void) #ifdef CONFIG_SMP static void __init kvm_smp_prepare_boot_cpu(void) { -#ifdef CONFIG_KVM_CLOCK WARN_ON(kvm_register_clock("primary cpu clock")); -#endif kvm_guest_cpu_init(); native_smp_prepare_boot_cpu(); } diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index f4b9b80e1b95..b3386ae3438b 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -957,7 +957,7 @@ void __init setup_arch(char **cmdline_p) initmem_init(); memblock_find_dma_reserve(); -#ifdef CONFIG_KVM_CLOCK +#ifdef CONFIG_KVM_GUEST kvmclock_init(); #endif -- cgit v1.2.3