Merge tag 'asoc-v6.5' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Updates for v6.5

A fairly quiet release from a core and framework point of view, but a
very big one from the point of view of new drivers:

 - More refectoring from Morimoto-san, this time mainly around DAI
   links and how we control the ordering of trigger() callbacks.
 - Convert a lot of drivers to use maple tree based caches.
 - Lots of work on the x86 driver stack.
 - Compressed audio support for Qualcomm.
 - Support for AMD SoundWire, Analog Devices SSM3515, Google Chameleon,
   Ingenic X1000, Intel systems with various CODECs, Longsoon platforms,
   Maxim MAX98388, Mediatek MT8188, Nuvoton NAU8825C, NXP platforms with
   NAU8822, Qualcomm WSA884x, StarFive JH7110, Texas Instruments TAS2781.

1 files changed, 17 insertions, 9 deletions

diff --git a/arch/arm64/kvm/fpsimd.c b/arch/arm64/kvm/fpsimd.c
index 1279949599b5..4c9dcd8fc939 100644
--- a/arch/arm64/kvm/fpsimd.c
+++ b/arch/arm64/kvm/fpsimd.c
@@ -81,26 +81,34 @@ void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu)
 
 	fpsimd_kvm_prepare();
 
+	/*
+	 * We will check TIF_FOREIGN_FPSTATE just before entering the
+	 * guest in kvm_arch_vcpu_ctxflush_fp() and override this to
+	 * FP_STATE_FREE if the flag set.
+	 */
 	vcpu->arch.fp_state = FP_STATE_HOST_OWNED;
 
 	vcpu_clear_flag(vcpu, HOST_SVE_ENABLED);
 	if (read_sysreg(cpacr_el1) & CPACR_EL1_ZEN_EL0EN)
 		vcpu_set_flag(vcpu, HOST_SVE_ENABLED);
 
-	/*
-	 * We don't currently support SME guests but if we leave
-	 * things in streaming mode then when the guest starts running
-	 * FPSIMD or SVE code it may generate SME traps so as a
-	 * special case if we are in streaming mode we force the host
-	 * state to be saved now and exit streaming mode so that we
-	 * don't have to handle any SME traps for valid guest
-	 * operations. Do this for ZA as well for now for simplicity.
-	 */
 	if (system_supports_sme()) {
 		vcpu_clear_flag(vcpu, HOST_SME_ENABLED);
 		if (read_sysreg(cpacr_el1) & CPACR_EL1_SMEN_EL0EN)
 			vcpu_set_flag(vcpu, HOST_SME_ENABLED);
 
+		/*
+		 * If PSTATE.SM is enabled then save any pending FP
+		 * state and disable PSTATE.SM. If we leave PSTATE.SM
+		 * enabled and the guest does not enable SME via
+		 * CPACR_EL1.SMEN then operations that should be valid
+		 * may generate SME traps from EL1 to EL1 which we
+		 * can't intercept and which would confuse the guest.
+		 *
+		 * Do the same for PSTATE.ZA in the case where there
+		 * is state in the registers which has not already
+		 * been saved, this is very unlikely to happen.
+		 */
 		if (read_sysreg_s(SYS_SVCR) & (SVCR_SM_MASK | SVCR_ZA_MASK)) {
 			vcpu->arch.fp_state = FP_STATE_FREE;
 			fpsimd_save_and_flush_cpu_state();