2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-25 05:34:00 +08:00
linux-next/arch/x86/include/uapi/asm
Vitaly Kuznetsov d176620277 x86/kvm/lapic: always disable MMIO interface in x2APIC mode
When VMX is used with flexpriority disabled (because of no support or
if disabled with module parameter) MMIO interface to lAPIC is still
available in x2APIC mode while it shouldn't be (kvm-unit-tests):

PASS: apic_disable: Local apic enabled in x2APIC mode
PASS: apic_disable: CPUID.1H:EDX.APIC[bit 9] is set
FAIL: apic_disable: *0xfee00030: 50014

The issue appears because we basically do nothing while switching to
x2APIC mode when APIC access page is not used. apic_mmio_{read,write}
only check if lAPIC is disabled before proceeding to actual write.

When APIC access is virtualized we correctly manipulate with VMX controls
in vmx_set_virtual_apic_mode() and we don't get vmexits from memory writes
in x2APIC mode so there's no issue.

Disabling MMIO interface seems to be easy. The question is: what do we
do with these reads and writes? If we add apic_x2apic_mode() check to
apic_mmio_in_range() and return -EOPNOTSUPP these reads and writes will
go to userspace. When lAPIC is in kernel, Qemu uses this interface to
inject MSIs only (see kvm_apic_mem_write() in hw/i386/kvm/apic.c). This
somehow works with disabled lAPIC but when we're in xAPIC mode we will
get a real injected MSI from every write to lAPIC. Not good.

The simplest solution seems to be to just ignore writes to the region
and return ~0 for all reads when we're in x2APIC mode. This is what this
patch does. However, this approach is inconsistent with what currently
happens when flexpriority is enabled: we allocate APIC access page and
create KVM memory region so in x2APIC modes all reads and writes go to
this pre-allocated page which is, btw, the same for all vCPUs.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20 00:26:43 +02:00
..
a.out.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
auxvec.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
bitsperlong.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
boot.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
bootparam.h x86/uapi: Fix asm/bootparam.h userspace compilation errors 2018-04-05 10:05:21 +02:00
byteorder.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debugreg.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
e820.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
errno.h
fcntl.h
hw_breakpoint.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
hwcap2.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ioctl.h
ioctls.h
ipcbuf.h
ist.h License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
Kbuild Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-01-30 17:58:07 -08:00
kvm_para.h KVM: X86: Implement PV IPIs in linux guest 2018-08-06 17:59:22 +02:00
kvm_perf.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
kvm.h x86/kvm/lapic: always disable MMIO interface in x2APIC mode 2018-09-20 00:26:43 +02:00
ldt.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
mce.h x86/MCE: Cleanup and complete struct mce fields definitions 2018-03-08 15:52:59 +01:00
mman.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
msgbuf.h x86/ipc: Fix x32 version of shmid64_ds and msqid64_ds 2018-04-27 17:06:29 +02:00
msr.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
mtrr.h License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
param.h
perf_regs.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
posix_types_32.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
posix_types_64.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
posix_types_x32.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
posix_types.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
prctl.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
processor-flags.h Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-12-29 17:02:49 -08:00
ptrace-abi.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
ptrace.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
resource.h
sembuf.h y2038: x86: Extend sysvipc data structures 2018-04-20 16:19:52 +02:00
setup.h create non-empty arch/x86/include/uapi/asm/ files 2012-12-17 17:15:11 -08:00
shmbuf.h x86/ipc: Fix x32 version of shmid64_ds and msqid64_ds 2018-04-27 17:06:29 +02:00
sigcontext32.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sigcontext.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
siginfo.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
signal.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
socket.h
sockios.h
stat.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
statfs.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
svm.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
swab.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
termbits.h
termios.h
types.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ucontext.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
unistd.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
vm86.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
vmx.h License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
vsyscall.h License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00