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From: Will Deacon <will@kernel.org>
To: kvmarm@lists.linux.dev
Cc: linux-arm-kernel@lists.infradead.org,
	Will Deacon <will@kernel.org>, Oliver Upton <oupton@kernel.org>,
	Marc Zyngier <maz@kernel.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Mark Rutland <mark.rutland@arm.com>
Subject: [PATCH] KVM: arm64: Don't populate TPIDR_EL2 in finalise_el2()
Date: Mon, 30 Mar 2026 16:29:26 +0100	[thread overview]
Message-ID: <20260330152927.26300-1-will@kernel.org> (raw)

When running with VHE, TPIDR_EL2 is only used for the percpu offset once
the ARM64_HAS_VIRT_HOST_EXTN capability has been detected, at which
point cpu_copy_el2regs() will populate its contents from TPIDR_EL1.

Remove the redundant initialisation of TPIDR_EL2 from finalise_el2().

Cc: Oliver Upton <oupton@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
---

I spotted this by inspection as part of an ill-fated (abandoned) attempt
at repurposing tpidr_elx for something else.

 arch/arm64/kernel/hyp-stub.S | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S
index 085bc9972f6b..8b8614c0b9a5 100644
--- a/arch/arm64/kernel/hyp-stub.S
+++ b/arch/arm64/kernel/hyp-stub.S
@@ -105,11 +105,9 @@ SYM_CODE_START_LOCAL(__finalise_el2)
 	msr_hcr_el2 x0
 	isb
 
-	// Use the EL1 allocated stack, per-cpu offset
+	// Use the EL1 allocated stack
 	mrs	x0, sp_el1
 	mov	sp, x0
-	mrs	x0, tpidr_el1
-	msr	tpidr_el2, x0
 
 	// FP configuration, vectors
 	mrs_s	x0, SYS_CPACR_EL12
-- 
2.53.0.1018.g2bb0e51243-goog


             reply	other threads:[~2026-03-30 15:29 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-30 15:29 Will Deacon [this message]
2026-03-31 10:18 ` [PATCH] KVM: arm64: Don't populate TPIDR_EL2 in finalise_el2() Mark Rutland

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