From: Sasha Levin <sashal@kernel.org>
To: stable@vger.kernel.org
Cc: Mark Brown <broonie@kernel.org>, Sasha Levin <sashal@kernel.org>
Subject: Re: [PATCH 6.13 v2 3/8] KVM: arm64: Remove host FPSIMD saving for non-protected KVM
Date: Fri, 21 Mar 2025 13:30:23 -0400 [thread overview]
Message-ID: <20250321125130-4bb62e76b2846200@stable.kernel.org> (raw)
In-Reply-To: <20250321-stable-sve-6-13-v2-3-3150e3370c40@kernel.org>
[ 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: 8eca7f6d5100b6997df4f532090bc3f7e0203bef
WARNING: Author mismatch between patch and upstream commit:
Backport author: Mark Brown<broonie@kernel.org>
Commit author: Mark Rutland<mark.rutland@arm.com>
Note: The patch differs from the upstream commit:
---
1: 8eca7f6d5100b ! 1: 9bf55741b1ec4 KVM: arm64: Remove host FPSIMD saving for non-protected KVM
@@ Metadata
## Commit message ##
KVM: arm64: Remove host FPSIMD saving for non-protected KVM
+ [ Upstream commit 8eca7f6d5100b6997df4f532090bc3f7e0203bef ]
+
Now that the host eagerly saves its own FPSIMD/SVE/SME state,
non-protected KVM never needs to save the host FPSIMD/SVE/SME state,
and the code to do this is never used. Protected KVM still needs to
@@ Commit message
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20250210195226.1215254-3-mark.rutland@arm.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
+ [CPACR_EL1_ZEN -> CPACR_ELx_ZEN -- broonie]
+ Signed-off-by: Mark Brown <broonie@kernel.org>
## arch/arm64/include/asm/kvm_host.h ##
@@ arch/arm64/include/asm/kvm_host.h: struct kvm_host_data {
@@ arch/arm64/kvm/fpsimd.c: void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu)
- *host_data_ptr(fpsimd_state) = NULL;
- *host_data_ptr(fpmr_ptr) = NULL;
- 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/hyp/include/hyp/switch.h ##
@@ arch/arm64/kvm/hyp/include/hyp/switch.h: static inline void __hyp_sve_save_host(
+
+ /* Re-enable SVE traps if not supported for the guest vcpu. */
+ if (!vcpu_has_sve(vcpu))
-+ cpacr_clear_set(CPACR_EL1_ZEN, 0);
++ cpacr_clear_set(CPACR_ELx_ZEN, 0);
+
+ } else {
+ __fpsimd_save_state(host_data_ptr(host_ctxt.fp_regs));
@@ arch/arm64/kvm/hyp/nvhe/switch.c: static bool kvm_handle_pvm_sys64(struct kvm_vc
-
- /* Re-enable SVE traps if not supported for the guest vcpu. */
- if (!vcpu_has_sve(vcpu))
-- cpacr_clear_set(CPACR_EL1_ZEN, 0);
+- cpacr_clear_set(CPACR_ELx_ZEN, 0);
-
- } else {
- __fpsimd_save_state(*host_data_ptr(fpsimd_state));
---
Results of testing on various branches:
| Branch | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-5.4.y | Success | Success |
next prev parent reply other threads:[~2025-03-21 17:30 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-03-21 0:10 [PATCH 6.13 v2 0/8] KVM: arm64: Backport of SVE fixes to v6.13 Mark Brown
2025-03-21 0:10 ` [PATCH 6.13 v2 1/8] KVM: arm64: Calculate cptr_el2 traps on activating traps Mark Brown
2025-03-21 17:28 ` Sasha Levin
2025-03-21 0:10 ` [PATCH 6.13 v2 2/8] KVM: arm64: Unconditionally save+flush host FPSIMD/SVE/SME state Mark Brown
2025-03-21 17:30 ` Sasha Levin
2025-03-21 0:10 ` [PATCH 6.13 v2 3/8] KVM: arm64: Remove host FPSIMD saving for non-protected KVM Mark Brown
2025-03-21 17:30 ` Sasha Levin [this message]
2025-03-21 0:10 ` [PATCH 6.13 v2 4/8] KVM: arm64: Remove VHE host restore of CPACR_EL1.ZEN Mark Brown
2025-03-21 17:27 ` Sasha Levin
2025-03-21 0:10 ` [PATCH 6.13 v2 5/8] KVM: arm64: Remove VHE host restore of CPACR_EL1.SMEN Mark Brown
2025-03-21 17:25 ` Sasha Levin
2025-03-21 0:10 ` [PATCH 6.13 v2 6/8] KVM: arm64: Refactor exit handlers Mark Brown
2025-03-21 17:28 ` Sasha Levin
2025-03-21 0:10 ` [PATCH 6.13 v2 7/8] KVM: arm64: Mark some header functions as inline Mark Brown
2025-03-21 17:29 ` Sasha Levin
2025-03-21 0:10 ` [PATCH 6.13 v2 8/8] KVM: arm64: Eagerly switch ZCR_EL{1,2} Mark Brown
2025-03-21 17:26 ` Sasha Levin
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