linux/arch/x86
Wanpeng Li f244deed7a KVM: VMX: Fix invalid guest state detection after task-switch emulation
This can be reproduced by EPT=1, unrestricted_guest=N, emulate_invalid_state=Y
or EPT=0, the trace of kvm-unit-tests/taskswitch2.flat is like below, it tries
to emulate invalid guest state task-switch:

kvm_exit: reason TASK_SWITCH rip 0x0 info 40000058 0
kvm_emulate_insn: 42000:0:0f 0b (0x2)
kvm_emulate_insn: 42000:0:0f 0b (0x2) failed
kvm_inj_exception: #UD (0x0)
kvm_entry: vcpu 0
kvm_exit: reason TASK_SWITCH rip 0x0 info 40000058 0
kvm_emulate_insn: 42000:0:0f 0b (0x2)
kvm_emulate_insn: 42000:0:0f 0b (0x2) failed
kvm_inj_exception: #UD (0x0)
......................

It appears that the task-switch emulation updates rflags (and vm86
flag) only after the segments are loaded, causing vmx->emulation_required
to be set, when in fact invalid guest state emulation is not needed.

This patch fixes it by updating vmx->emulation_required after the
rflags (and vm86 flag) is updated in task-switch emulation.

Thanks Radim for moving the update to vmx__set_flags and adding Paolo's
suggestion for the check.

Suggested-by: Nadav Amit <nadav.amit@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-07-20 17:00:00 +02:00
..
boot include/linux/string.h: add the option of fortified string.h functions 2017-07-12 16:26:03 -07:00
configs Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-05-01 20:51:12 -07:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-07-14 22:49:50 -07:00
entry Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm 2017-07-08 12:17:25 -07:00
events Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 18:08:06 -07:00
hyperv char/misc patches for 4.12-rc1 2017-05-04 19:15:35 -07:00
ia32 sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h> 2017-03-02 08:42:36 +01:00
include Merge branch 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-07-15 11:17:52 -07:00
kernel Second batch of KVM updates for v4.13 2017-07-15 10:18:16 -07:00
kvm KVM: VMX: Fix invalid guest state detection after task-switch emulation 2017-07-20 17:00:00 +02:00
lguest Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-05-01 20:51:12 -07:00
lib include/linux/string.h: add the option of fortified string.h functions 2017-07-12 16:26:03 -07:00
math-emu x86/ldt: Rename ldt_struct::size to ::nr_entries 2017-06-08 09:28:21 +02:00
mm x86/mmap: properly account for stack randomization in mmap_base 2017-07-12 16:26:03 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-07-05 12:31:59 -07:00
oprofile x86/oprofile/nmi: Convert to hotplug state machine 2016-11-22 23:34:43 +01:00
pci pci-v4.13-changes 2017-07-08 15:51:57 -07:00
platform x86/platform/uv/BAU: Minor cleanup, make some local functions static 2017-07-04 15:52:37 +02:00
power x86/boot/e820: Introduce the bootloader provided e820_table_firmware[] table 2017-07-05 10:09:02 +02:00
purgatory kasan: do not sanitize kexec purgatory 2017-03-31 17:13:30 -07:00
ras x86/mce: Merge mce_amd_inj into mce-inject 2017-06-14 07:32:07 +02:00
realmode x86/boot/64: Rename init_level4_pgt and early_level4_pgt 2017-06-13 08:56:55 +02:00
tools x86/tools: Fix gcc-7 warning in relocs.c 2016-12-19 11:50:24 +01:00
um Merge branch 'for-linus-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2017-07-15 10:49:33 -07:00
video
xen kexec: move vmcoreinfo out of the kernel's .bss section 2017-07-12 16:25:59 -07:00
.gitignore
Kbuild Drivers: hv vmbus: Move Hypercall page setup out of common code 2017-01-19 11:42:07 +01:00
Kconfig include/linux/string.h: add the option of fortified string.h functions 2017-07-12 16:26:03 -07:00
Kconfig.cpu
Kconfig.debug usb/early: Add driver for xhci debug capability 2017-03-21 12:30:05 +01:00
Makefile Kbuild updates for v4.13 2017-07-07 14:09:24 -07:00
Makefile_32.cpu kbuild: remove cc-option-align 2017-06-25 12:43:00 +09:00
Makefile.um