[PATCH v3 56/62] arm/acpi: Deny MMIO access of UART
shannon.zhao at linaro.org
shannon.zhao at linaro.org
Tue Nov 17 01:40:55 PST 2015
From: Shannon Zhao <shannon.zhao at linaro.org>
Firstly it permits full MMIO capabilities for Dom0. Then deny MMIO
access of UART device.
Signed-off-by: Shannon Zhao <shannon.zhao at linaro.org>
---
xen/arch/arm/domain_build.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 6945f89..9532807 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -1360,6 +1360,32 @@ static int prepare_dtb(struct domain *d, struct kernel_info *kinfo)
#define XEN_HYPERVISOR_ID 0x000058656E564D4D /* "XenVMM" */
#define ACPI_DOM0_FDT_MIN_SIZE 4096
+static int acpi_iomem_deny_access(struct domain *d)
+{
+ acpi_status status;
+ struct acpi_table_spcr *spcr=NULL;
+ unsigned long gfn;
+ int rc;
+
+ /* Firstly permit full MMIO capabilities. */
+ rc = iomem_permit_access(d, 0UL, ~0UL);
+ if (rc)
+ return rc;
+
+ status = acpi_get_table(ACPI_SIG_SPCR, 0,
+ (struct acpi_table_header **)&spcr);
+
+ if ( ACPI_FAILURE(status) )
+ {
+ printk("Failed to get SPCR table\n");
+ return -EINVAL;
+ }
+
+ gfn = spcr->serial_port.address >> PAGE_SHIFT;
+ /* Deny MMIO access for UART */
+ return iomem_deny_access(d, gfn, gfn + 1);
+}
+
static int acpi_route_spi(struct domain *d)
{
int i, res;
@@ -1930,6 +1956,10 @@ static int prepare_acpi(struct domain *d, struct kernel_info *kinfo)
if ( rc != 0 )
return rc;
+ rc = acpi_iomem_deny_access(d);
+ if ( rc != 0 )
+ return rc;
+
return 0;
}
#else
--
2.1.0
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