[PATCH 16/16] arm64: Register earlycon fixmap with the MMIO guard
From: Marc Zyngier <maz@kernel.org>
Date: 2021-07-15 16:54:04
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 | 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
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel