KVM: arm64: Fix TRFCR_EL1/PMSCR_EL1 access in hVHE mode

When running in hVHE mode, EL1 accesses are performed with the EL12
accessor, as we run with HCR_EL2.E2H=1.

Unfortunately, both PMSCR_EL1 and TRFCR_EL1 are used with the
EL1 accessor, meaning that we actually affect the EL2 state. Duh.

Switch to using the {read,write}_sysreg_el1() helpers that will do
the right thing in all circumstances.

Note that the 'Fixes:' tag doesn't represent the point where the bug
was introduced (there is no such point), but the first practical point
where the hVHE feature is usable.

Cc: James Clark <james.clark@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Fixes: 38cba55008e5 ("KVM: arm64: Force HCR_E2H in guest context when ARM64_KVM_HVHE is set")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240229145417.3606279-1-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

diff --git a/arch/arm64/kvm/hyp/nvhe/debug-sr.c b/arch/arm64/kvm/hyp/nvhe/debug-sr.c
index 4558c02eb352d06be1c5861ea22a956c2c05954f..7746ea507b6f00ea0214310a5f52c840e3435b11 100644 (file)
--- a/arch/arm64/kvm/hyp/nvhe/debug-sr.c
+++ b/arch/arm64/kvm/hyp/nvhe/debug-sr.c
@@ -31,8 +31,8 @@ static void __debug_save_spe(u64 *pmscr_el1)
                return;
 
        /* Yes; save the control register and disable data generation */
-       *pmscr_el1 = read_sysreg_s(SYS_PMSCR_EL1);
-       write_sysreg_s(0, SYS_PMSCR_EL1);
+       *pmscr_el1 = read_sysreg_el1(SYS_PMSCR);
+       write_sysreg_el1(0, SYS_PMSCR);
        isb();
 
        /* Now drain all buffered data to memory */
@@ -48,7 +48,7 @@ static void __debug_restore_spe(u64 pmscr_el1)
        isb();
 
        /* Re-enable data generation */
-       write_sysreg_s(pmscr_el1, SYS_PMSCR_EL1);
+       write_sysreg_el1(pmscr_el1, SYS_PMSCR);
 }
 
 static void __debug_save_trace(u64 *trfcr_el1)
@@ -63,8 +63,8 @@ static void __debug_save_trace(u64 *trfcr_el1)
         * Since access to TRFCR_EL1 is trapped, the guest can't
         * modify the filtering set by the host.
         */
-       *trfcr_el1 = read_sysreg_s(SYS_TRFCR_EL1);
-       write_sysreg_s(0, SYS_TRFCR_EL1);
+       *trfcr_el1 = read_sysreg_el1(SYS_TRFCR);
+       write_sysreg_el1(0, SYS_TRFCR);
        isb();
        /* Drain the trace buffer to memory */
        tsb_csync();
@@ -76,7 +76,7 @@ static void __debug_restore_trace(u64 trfcr_el1)
                return;
 
        /* Restore trace filter controls */
-       write_sysreg_s(trfcr_el1, SYS_TRFCR_EL1);
+       write_sysreg_el1(trfcr_el1, SYS_TRFCR);
 }
 
 void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu)