On initialising the MMIO guard infrastructure, register the
earlycon mapping if present.
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
arch/arm64/mm/ioremap.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/arch/arm64/mm/ioremap.c b/arch/arm64/mm/ioremap.c
index d82b63bcc554..a27b58e03c93 100644
--- a/arch/arm64/mm/ioremap.c
+++ b/arch/arm64/mm/ioremap.c
@@ -32,6 +32,18 @@ static int __init ioremap_guard_setup(char *str)
}
early_param("ioremap_guard", ioremap_guard_setup);
+static void fixup_fixmap(void)
+{
+ unsigned long addr = __fix_to_virt(FIX_EARLYCON_MEM_BASE);
+ pte_t *ptep = __get_fixmap_pte(FIX_EARLYCON_MEM_BASE);
+
+ if (!ptep)
+ return;
+
+ ioremap_page_range_hook(addr, addr + PAGE_SIZE, __pte_to_phys(*ptep),
+ __pgprot(pte_val(*ptep) & PTE_ATTRINDX_MASK));
+}
+
void kvm_init_ioremap_services(void)
{
struct arm_smccc_res res;
@@ -55,6 +67,7 @@ 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);
--
2.30.2
