From ef4a035f8aee9ae8c29200560dc74907d33a65af Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 1 Jul 2021 09:34:12 +0100 Subject: [PATCH] ANDROID: arm64: Register earlycon fixmap with the MMIO guard On initialising the MMIO guard infrastructure, register the earlycon mapping if present. Signed-off-by: Marc Zyngier Bug: 233587962 Change-Id: I379387253d08e2414fa386a3360a45391da7d90d Signed-off-by: Will Deacon Signed-off-by: Quentin Perret --- arch/arm64/mm/ioremap.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/arm64/mm/ioremap.c b/arch/arm64/mm/ioremap.c index 8d0f8d7dbe53..e91a79c5e3df 100644 --- a/arch/arm64/mm/ioremap.c +++ b/arch/arm64/mm/ioremap.c @@ -68,6 +68,17 @@ static int __init ioremap_guard_setup(char *str) } early_param("ioremap_guard", ioremap_guard_setup); +static void fixup_fixmap(void) +{ + pte_t *ptep = __get_fixmap_pte(FIX_EARLYCON_MEM_BASE); + + if (!ptep) + return; + + ioremap_phys_range_hook(__pte_to_phys(*ptep), PAGE_SIZE, + __pgprot(pte_val(*ptep) & PTE_ATTRINDX_MASK)); +} + void kvm_init_ioremap_services(void) { struct arm_smccc_res res; @@ -91,6 +102,7 @@ void kvm_init_ioremap_services(void) &res); if (res.a0 == SMCCC_RET_SUCCESS) { static_branch_enable(&ioremap_guard_key); + fixup_fixmap(); pr_info("Using KVM MMIO guard for ioremap\n"); } else { pr_warn("KVM MMIO guard registration failed (%ld)\n", res.a0);