diff options
| author | Remi Denis-Courmont <remi.denis.courmont@huawei.com> | 2019-01-26 08:52:10 +0200 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2019-02-01 15:23:51 +0000 |
| commit | f6768aa1b4c6a80448eabd22bb9b4123c709caea (patch) | |
| tree | 585951c8095ce4bd679387276a0739809cc28b7c /target | |
| parent | 87877543b14feebf1bc4fd336d41901b036acf98 (diff) | |
target/arm: fix AArch64 virtual address space size
Since QEMU does not support the ARMv8.2-LVA, Large Virtual Address,
extension (yet), the VA address space is 48-bits plus a sign bit. User
mode can only handle the positive half of the address space, so that
makes a limit of 48 bits.
(With LVA, it would be 53 and 52 bits respectively.)
The incorrectly large address space conflicts with PAuth instructions,
which use bits 48-54 and 56-63 for the pointer authentication code. This
also conflicts with (as yet unsupported by QEMU) data tagging and with
the ARMv8.5-MTE extension.
Signed-off-by: Remi Denis-Courmont <remi.denis.courmont@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'target')
| -rw-r--r-- | target/arm/cpu.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/target/arm/cpu.h b/target/arm/cpu.h index 63934a200a..a68bcc9fed 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -2512,7 +2512,7 @@ bool write_cpustate_to_list(ARMCPU *cpu); #if defined(TARGET_AARCH64) # define TARGET_PHYS_ADDR_SPACE_BITS 48 -# define TARGET_VIRT_ADDR_SPACE_BITS 64 +# define TARGET_VIRT_ADDR_SPACE_BITS 48 #else # define TARGET_PHYS_ADDR_SPACE_BITS 40 # define TARGET_VIRT_ADDR_SPACE_BITS 32 |