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| author | Dave Martin <Dave.Martin@arm.com> | 2018-09-28 14:39:10 +0100 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2019-03-29 14:41:52 +0000 |
| commit | d06b76be8dad2e2fa62f68264887cc295d67a3ef (patch) | |
| tree | 38203fa633b3e90e6d6e0c95eb766520fb5b30f3 /arch/arm64/include/asm/fpsimd.h | |
| parent | 8b08e8401fb49fe1274a91bb5fa981c2f819589c (diff) | |
| download | blackbird-op-linux-d06b76be8dad2e2fa62f68264887cc295d67a3ef.tar.gz blackbird-op-linux-d06b76be8dad2e2fa62f68264887cc295d67a3ef.zip | |
arm64/sve: Check SVE virtualisability
Due to the way the effective SVE vector length is controlled and
trapped at different exception levels, certain mismatches in the
sets of vector lengths supported by different physical CPUs in the
system may prevent straightforward virtualisation of SVE at parity
with the host.
This patch analyses the extent to which SVE can be virtualised
safely without interfering with migration of vcpus between physical
CPUs, and rejects late secondary CPUs that would erode the
situation further.
It is left up to KVM to decide what to do with this information.
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'arch/arm64/include/asm/fpsimd.h')
| -rw-r--r-- | arch/arm64/include/asm/fpsimd.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index dd1ad3950ef5..964adc9f312d 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -87,6 +87,7 @@ extern void sve_kernel_enable(const struct arm64_cpu_capabilities *__unused); extern u64 read_zcr_features(void); extern int __ro_after_init sve_max_vl; +extern int __ro_after_init sve_max_virtualisable_vl; #ifdef CONFIG_ARM64_SVE |
