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| author | Kristina Martsenko <kristina.martsenko@arm.com> | 2017-11-16 17:58:20 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-12-16 10:32:27 +0100 |
| commit | 140db397a1440a325a144af1defa458e8330680b (patch) | |
| tree | 6c48c6040efd0b218a8d73dac9975d841153e686 /arch | |
| parent | fc93b6293c4199c210fb5a102c3b61b351b86b24 (diff) | |
| download | linux-stable-140db397a1440a325a144af1defa458e8330680b.tar.gz linux-stable-140db397a1440a325a144af1defa458e8330680b.tar.bz2 linux-stable-140db397a1440a325a144af1defa458e8330680b.zip | |
arm64: KVM: fix VTTBR_BADDR_MASK BUG_ON off-by-one
commit 26aa7b3b1c0fb3f1a6176a0c1847204ef4355693 upstream.
VTTBR_BADDR_MASK is used to sanity check the size and alignment of the
VTTBR address. It seems to currently be off by one, thereby only
allowing up to 47-bit addresses (instead of 48-bit) and also
insufficiently checking the alignment. This patch fixes it.
As an example, with 4k pages, before this patch we have:
PHYS_MASK_SHIFT = 48
VTTBR_X = 37 - 24 = 13
VTTBR_BADDR_SHIFT = 13 - 1 = 12
VTTBR_BADDR_MASK = ((1 << 35) - 1) << 12 = 0x00007ffffffff000
Which is wrong, because the mask doesn't allow bit 47 of the VTTBR
address to be set, and only requires the address to be 12-bit (4k)
aligned, while it actually needs to be 13-bit (8k) aligned because we
concatenate two 4k tables.
With this patch, the mask becomes 0x0000ffffffffe000, which is what we
want.
Fixes: 0369f6a34b9f ("arm64: KVM: EL2 register definitions")
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/include/asm/kvm_arm.h | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index 8afb863f5a9e..333ddd45dd1f 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -160,8 +160,7 @@ #define VTTBR_X (37 - VTCR_EL2_T0SZ_40B) #endif -#define VTTBR_BADDR_SHIFT (VTTBR_X - 1) -#define VTTBR_BADDR_MASK (((UL(1) << (PHYS_MASK_SHIFT - VTTBR_X)) - 1) << VTTBR_BADDR_SHIFT) +#define VTTBR_BADDR_MASK (((UL(1) << (PHYS_MASK_SHIFT - VTTBR_X)) - 1) << VTTBR_X) #define VTTBR_VMID_SHIFT (UL(48)) #define VTTBR_VMID_MASK (UL(0xFF) << VTTBR_VMID_SHIFT) |