linux

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Sean Christopherson 032fd28ed5 KVM: nVMX: Ensure 64-bit shift when checking VMFUNC bitmap

[ Upstream commit 0e75225dfa4c5d5d51291f54a3d2d5895bad38da ]

Use BIT_ULL() instead of an open-coded shift to check whether or not a
function is enabled in L1's VMFUNC bitmap.  This is a benign bug as KVM
supports only bit 0, and will fail VM-Enter if any other bits are set,
i.e. bits 63:32 are guaranteed to be zero.

Note, "function" is bounded by hardware as VMFUNC will #UD before taking
a VM-Exit if the function is greater than 63.

Before:
  if ((vmcs12->vm_function_control & (1 << function)) == 0)
   0x000000000001a916 <+118>:	mov    $0x1,%eax
   0x000000000001a91b <+123>:	shl    %cl,%eax
   0x000000000001a91d <+125>:	cltq
   0x000000000001a91f <+127>:	and    0x128(%rbx),%rax

After:
  if (!(vmcs12->vm_function_control & BIT_ULL(function & 63)))
   0x000000000001a955 <+117>:	mov    0x128(%rbx),%rdx
   0x000000000001a95c <+124>:	bt     %rax,%rdx

Fixes: 27c42a1bb867 ("KVM: nVMX: Enable VMFUNC for the L1 hypervisor")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210609234235.1244004-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

2021-07-14 16:53:23 +02:00

alpha

alpha: fix annotation of io{read,write}{16,32}be()

2020-08-26 10:40:58 +02:00

arc

ARCv2: save ABI registers across signal handling

2021-06-23 14:41:29 +02:00

arm

ARM: dts: at91: sama5d4: fix pinctrl muxing

2021-07-14 16:53:02 +02:00

arm64

arm64/mm: Fix ttbr0 values stored in struct thread_info for software-pan