linux_dsm_epyc7002/arch
Sean Christopherson f958bd2314 KVM: x86: Fix potential put_fpu() w/o load_fpu() on MPX platform
Unlike most state managed by XSAVE, MPX is initialized to zero on INIT.
Because INITs are usually recognized in the context of a VCPU_RUN call,
kvm_vcpu_reset() puts the guest's FPU so that the FPU state is resident
in memory, zeros the MPX state, and reloads FPU state to hardware.  But,
in the unlikely event that an INIT is recognized during
kvm_arch_vcpu_ioctl_get_mpstate() via kvm_apic_accept_events(),
kvm_vcpu_reset() will call kvm_put_guest_fpu() without a preceding
kvm_load_guest_fpu() and corrupt the guest's FPU state (and possibly
userspace's FPU state as well).

Given that MPX is being removed from the kernel[*], fix the bug with the
simple-but-ugly approach of loading the guest's FPU during
KVM_GET_MP_STATE.

[*] See commit f240652b60 ("x86/mpx: Remove MPX APIs").

Fixes: f775b13eed ("x86,kvm: move qemu/guest FPU switching out to vcpu_run")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:01 +01:00
..
alpha alpha: use pgtable-nopud instead of 4level-fixup 2019-12-04 19:44:14 -08:00
arc treewide: Use sizeof_field() macro 2019-12-09 10:36:44 -08:00
arm KVM/arm fixes for .5.5, take #1 2019-12-18 17:47:38 +01:00
arm64 mm/memory_hotplug: shrink zones when offlining memory 2020-01-04 13:55:08 -08:00
c6x c6x: use pgtable-nopud instead of 4level-fixup 2019-12-04 19:44:15 -08:00
csky dma-mapping updates for 5.5-rc1 2019-11-28 11:16:43 -08:00
h8300
hexagon hexagon: define ioremap_uc 2020-01-04 13:55:09 -08:00
ia64 mm/memory_hotplug: shrink zones when offlining memory 2020-01-04 13:55:08 -08:00
m68k Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2019-12-05 12:20:42 -08:00
microblaze microblaze: use pgtable-nopmd instead of 4level-fixup 2019-12-04 19:44:15 -08:00
mips A collection of MIPS fixes: 2020-01-04 14:16:57 -08:00
nds32 nds32: use pgtable-nopmd instead of 4level-fixup 2019-12-04 19:44:15 -08:00
nios2 nios2: Fix ioremap 2019-12-12 16:34:33 +08:00
openrisc OpenRISC updates for 5.5 2019-12-02 17:18:43 -08:00
parisc parisc: Fix compiler warnings in debug_core.c 2019-12-20 21:01:42 +01:00
powerpc mm/memory_hotplug: shrink zones when offlining memory 2020-01-04 13:55:08 -08:00
riscv riscv: prefix IRQ_ macro names with an RV_ namespace 2020-01-04 21:48:59 -08:00
s390 mm/memory_hotplug: shrink zones when offlining memory 2020-01-04 13:55:08 -08:00
sh mm/memory_hotplug: shrink zones when offlining memory 2020-01-04 13:55:08 -08:00
sparc treewide: Use sizeof_field() macro 2019-12-09 10:36:44 -08:00
um um: add support for folded p4d page tables 2019-12-04 19:44:15 -08:00
unicore32 generic ioremap support 2019-11-28 10:57:12 -08:00
x86 KVM: x86: Fix potential put_fpu() w/o load_fpu() on MPX platform 2020-01-08 18:16:01 +01:00
xtensa arch: sembuf.h: make uapi asm/sembuf.h self-contained 2019-12-04 19:44:14 -08:00
.gitignore
Kconfig arch/Kconfig: fix indentation 2019-12-04 19:44:12 -08:00