[ Sasha's backport helper bot ]
Hi,
✅ All tests passed successfully. No issues detected. No action required from the submitter.
The upstream commit SHA1 provided is correct: fbc7e61195e23f744814e78524b73b59faa54ab4
WARNING: Author mismatch between patch and upstream commit: Backport author: Mark Brownbroonie@kernel.org Commit author: Mark Rutlandmark.rutland@arm.com
Status in newer kernel trees: 6.13.y | Present (different SHA1: 8361da508047) 6.12.y | Present (different SHA1: 6942e1f47a00)
Note: The patch differs from the upstream commit: --- 1: fbc7e61195e23 ! 1: 2d0c224eda446 KVM: arm64: Unconditionally save+flush host FPSIMD/SVE/SME state @@ Metadata ## Commit message ## KVM: arm64: Unconditionally save+flush host FPSIMD/SVE/SME state
+ [ Upstream commit fbc7e61195e23f744814e78524b73b59faa54ab4 ] + There are several problems with the way hyp code lazily saves the host's FPSIMD/SVE state, including:
@@ Commit message Reviewed-by: Oliver Upton oliver.upton@linux.dev Link: https://lore.kernel.org/r/20250210195226.1215254-2-mark.rutland@arm.com Signed-off-by: Marc Zyngier maz@kernel.org + [ Mark: Handle vcpu/host flag conflict ] + Signed-off-by: Mark Rutland mark.rutland@arm.com + Signed-off-by: Mark Brown broonie@kernel.org
## arch/arm64/kernel/fpsimd.c ## @@ arch/arm64/kernel/fpsimd.c: void fpsimd_signal_preserve_current_state(void) @@ arch/arm64/kvm/fpsimd.c: void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu) + * When the host may use SME, fpsimd_save_and_flush_cpu_state() ensures + * that PSTATE.{SM,ZA} == {0,0}. */ -- *host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED; -- *host_data_ptr(fpsimd_state) = kern_hyp_va(¤t->thread.uw.fpsimd_state); -- *host_data_ptr(fpmr_ptr) = kern_hyp_va(¤t->thread.uw.fpmr); +- vcpu->arch.fp_state = FP_STATE_HOST_OWNED; + fpsimd_save_and_flush_cpu_state(); -+ *host_data_ptr(fp_owner) = FP_STATE_FREE; -+ *host_data_ptr(fpsimd_state) = NULL; -+ *host_data_ptr(fpmr_ptr) = NULL; ++ vcpu->arch.fp_state = FP_STATE_FREE;
- host_data_clear_flag(HOST_SVE_ENABLED); + vcpu_clear_flag(vcpu, HOST_SVE_ENABLED); if (read_sysreg(cpacr_el1) & CPACR_EL1_ZEN_EL0EN) @@ arch/arm64/kvm/fpsimd.c: void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu) - host_data_clear_flag(HOST_SME_ENABLED); + vcpu_clear_flag(vcpu, HOST_SME_ENABLED); if (read_sysreg(cpacr_el1) & CPACR_EL1_SMEN_EL0EN) - host_data_set_flag(HOST_SME_ENABLED); + vcpu_set_flag(vcpu, HOST_SME_ENABLED); - - /* - * If PSTATE.SM is enabled then save any pending FP @@ arch/arm64/kvm/fpsimd.c: void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu) - * been saved, this is very unlikely to happen. - */ - if (read_sysreg_s(SYS_SVCR) & (SVCR_SM_MASK | SVCR_ZA_MASK)) { -- *host_data_ptr(fp_owner) = FP_STATE_FREE; +- vcpu->arch.fp_state = FP_STATE_FREE; - fpsimd_save_and_flush_cpu_state(); - } } + }
- /* ---
Results of testing on various branches:
| Branch | Patch Apply | Build Test | |---------------------------|-------------|------------| | stable/linux-6.12.y | Success | Success |