linux/arch
Maxim Levitsky c53bbe2145 KVM: x86: SVM: don't passthrough SMAP/SMEP/PKE bits in !NPT && !gCR0.PG case
When the guest doesn't enable paging, and NPT/EPT is disabled, we
use guest't paging CR3's as KVM's shadow paging pointer and
we are technically in direct mode as if we were to use NPT/EPT.

In direct mode we create SPTEs with user mode permissions
because usually in the direct mode the NPT/EPT doesn't
need to restrict access based on guest CPL
(there are MBE/GMET extenstions for that but KVM doesn't use them).

In this special "use guest paging as direct" mode however,
and if CR4.SMAP/CR4.SMEP are enabled, that will make the CPU
fault on each access and KVM will enter endless loop of page faults.

Since page protection doesn't have any meaning in !PG case,
just don't passthrough these bits.

The fix is the same as was done for VMX in commit:
commit 656ec4a492 ("KVM: VMX: fix SMEP and SMAP without EPT")

This fixes the boot of windows 10 without NPT for good.
(Without this patch, BSP boots, but APs were stuck in endless
loop of page faults, causing the VM boot with 1 CPU)

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Message-Id: <20220207155447.840194-2-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-02-08 13:30:47 -05:00
..
alpha bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
arc bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
arm lib/crypto: blake2s: avoid indirect calls to compression function for Clang CFI 2022-02-04 19:22:32 +01:00
arm64 KVM/arm64 fixes for 5.17, take #2 2022-02-05 00:58:25 -05:00
csky bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
h8300 bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
hexagon bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
ia64 ia64: make IA64_MCA_RECOVERY bool instead of tristate 2022-01-30 09:56:58 +02:00
m68k bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
microblaze Kbuild updates for v5.17 2022-01-19 11:15:19 +02:00
mips ARM: 2022-02-05 09:55:59 -08:00
nds32 Kbuild updates for v5.17 2022-01-19 11:15:19 +02:00
nios2 Kbuild updates for v5.17 2022-01-19 11:15:19 +02:00
openrisc bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
parisc bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
powerpc powerpc/64s/interrupt: Fix decrementer storm 2022-01-25 16:50:10 +11:00
riscv KVM/arm64 fixes for 5.17, take #2 2022-02-05 00:58:25 -05:00
s390 s390/hypfs: include z/VM guests with access control group set 2022-01-26 18:42:39 +01:00
sh bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
sparc bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
um virtio,vdpa,qemu_fw_cfg: features, cleanups, fixes 2022-01-18 10:05:48 +02:00
x86 KVM: x86: SVM: don't passthrough SMAP/SMEP/PKE bits in !NPT && !gCR0.PG case 2022-02-08 13:30:47 -05:00
xtensa bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
.gitignore
Kconfig Merge branch 'akpm' (patches from Andrew) 2022-01-20 10:41:01 +02:00