From: Will Deacon Date: Mon, 18 May 2026 15:31:26 +0000 (+0100) Subject: KVM: arm64: Don't populate TPIDR_EL2 in finalise_el2() X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=4cceeb8da363ac5127b147ee7345104743f53e9d;p=thirdparty%2Flinux.git KVM: arm64: Don't populate TPIDR_EL2 in finalise_el2() Currently, it is not necessary for __finalise_el2() to configure TPIDR_EL2: * The hyp stub code does not consume the value of TPIDR_EL2. * On the boot cpu, TPIDR_EL1 is used for the percpu offset until the ARM64_HAS_VIRT_HOST_EXTN cpucap is detected and boot alternatives are patched. Before boot alternatives are patched, cpu_copy_el2regs() will copy TPIDR_EL1 into TPIDR_EL2. It is not necessary for __finalise_el2() to initialise TPIDR_EL2 before this. * Secondary CPUs are brought up after boot alternatives have been patched, and __secondary_switched() will initialize TPIDR_EL2 in 'init_cpu_task', after finalise_el2() calls __finalise_el2() * KVM hyp code which may consume TPIDR_EL2 is brought up after all secondaries have been booted, once TPIDR_El2 has been configured on all CPUs. Remove the redundant initialisation from __finalise_el2(). Cc: Oliver Upton Cc: Marc Zyngier Cc: Catalin Marinas Reviewed-by: Mark Rutland Signed-off-by: Will Deacon Reviewed-by: Marc Zyngier Link: https://patch.msgid.link/20260518153127.6078-1-will@kernel.org Signed-off-by: Marc Zyngier --- diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S index 634ddc9042444..37c6976e44a4c 100644 --- a/arch/arm64/kernel/hyp-stub.S +++ b/arch/arm64/kernel/hyp-stub.S @@ -104,11 +104,9 @@ SYM_CODE_START_LOCAL(__finalise_el2) mov_q x0, HCR_HOST_VHE_FLAGS msr_hcr_el2 x0 - // 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