diff options
| author | Fuad Tabba <tabba@google.com> | 2024-06-03 14:28:47 +0200 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2024-06-04 16:06:33 +0200 |
| commit | 66d5b53e20a6e00b7ce3b652a3e2db967f7b33d0 (patch) | |
| tree | 18f77f59a02c28da6abe85df94d16d2dbde15c03 /arch/arm64/include/asm | |
| parent | KVM: arm64: Specialize handling of host fpsimd state on trap (diff) | |
| download | linux-66d5b53e20a6e00b7ce3b652a3e2db967f7b33d0.tar.xz linux-66d5b53e20a6e00b7ce3b652a3e2db967f7b33d0.zip | |
KVM: arm64: Allocate memory mapped at hyp for host sve state in pKVM
Protected mode needs to maintain (save/restore) the host's sve
state, rather than relying on the host kernel to do that. This is
to avoid leaking information to the host about guests and the
type of operations they are performing.
As a first step towards that, allocate memory mapped at hyp, per
cpu, for the host sve state. The following patch will use this
memory to save/restore the host state.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20240603122852.3923848-6-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'arch/arm64/include/asm')
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 17 | ||||
| -rw-r--r-- | arch/arm64/include/asm/kvm_hyp.h | 1 | ||||
| -rw-r--r-- | arch/arm64/include/asm/kvm_pkvm.h | 9 |
3 files changed, 27 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 8170c04fde91..90df7ccec5f4 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -76,6 +76,7 @@ static inline enum kvm_mode kvm_get_mode(void) { return KVM_MODE_NONE; }; DECLARE_STATIC_KEY_FALSE(userspace_irqchip_in_use); extern unsigned int __ro_after_init kvm_sve_max_vl; +extern unsigned int __ro_after_init kvm_host_sve_max_vl; int __init kvm_arm_init_sve(void); u32 __attribute_const__ kvm_target_cpu(void); @@ -521,6 +522,20 @@ struct kvm_cpu_context { u64 *vncr_array; }; +struct cpu_sve_state { + __u64 zcr_el1; + + /* + * Ordering is important since __sve_save_state/__sve_restore_state + * relies on it. + */ + __u32 fpsr; + __u32 fpcr; + + /* Must be SVE_VQ_BYTES (128 bit) aligned. */ + __u8 sve_regs[]; +}; + /* * This structure is instantiated on a per-CPU basis, and contains * data that is: @@ -534,7 +549,9 @@ struct kvm_cpu_context { */ struct kvm_host_data { struct kvm_cpu_context host_ctxt; + struct user_fpsimd_state *fpsimd_state; /* hyp VA */ + struct cpu_sve_state *sve_state; /* hyp VA */ /* Ownership of the FP regs */ enum { diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h index 686cce7e4e96..b05bceca3385 100644 --- a/arch/arm64/include/asm/kvm_hyp.h +++ b/arch/arm64/include/asm/kvm_hyp.h @@ -143,5 +143,6 @@ extern u64 kvm_nvhe_sym(id_aa64smfr0_el1_sys_val); extern unsigned long kvm_nvhe_sym(__icache_flags); extern unsigned int kvm_nvhe_sym(kvm_arm_vmid_bits); +extern unsigned int kvm_nvhe_sym(kvm_host_sve_max_vl); #endif /* __ARM64_KVM_HYP_H__ */ diff --git a/arch/arm64/include/asm/kvm_pkvm.h b/arch/arm64/include/asm/kvm_pkvm.h index ad9cfb5c1ff4..cd56acd9a842 100644 --- a/arch/arm64/include/asm/kvm_pkvm.h +++ b/arch/arm64/include/asm/kvm_pkvm.h @@ -128,4 +128,13 @@ static inline unsigned long hyp_ffa_proxy_pages(void) return (2 * KVM_FFA_MBOX_NR_PAGES) + DIV_ROUND_UP(desc_max, PAGE_SIZE); } +static inline size_t pkvm_host_sve_state_size(void) +{ + if (!system_supports_sve()) + return 0; + + return size_add(sizeof(struct cpu_sve_state), + SVE_SIG_REGS_SIZE(sve_vq_from_vl(kvm_host_sve_max_vl))); +} + #endif /* __ARM64_KVM_PKVM_H__ */ |