[PATCH v2 16/16] arm64: Register earlycon fixmap with the MMIO guard
From: Marc Zyngier <maz@kernel.org>
Date: 2021-10-04 17:57:15
Also in:
kvm, kvmarm, lkml
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
On initialising the MMIO guard infrastructure, register the earlycon mapping if present. Signed-off-by: Marc Zyngier <maz@kernel.org> --- 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 62b715ea31e5..0e10b788500c 100644
--- a/arch/arm64/mm/ioremap.c
+++ b/arch/arm64/mm/ioremap.c@@ -39,6 +39,17 @@ 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;
@@ -62,6 +73,7 @@ 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
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