diff options
| author | Seth Forshee <seth.forshee@canonical.com> | 2012-08-08 08:27:03 -0500 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2012-10-10 03:31:13 +0100 |
| commit | b4723adc0c336e153b6396f8c0e3f396cd9e9b5d (patch) | |
| tree | ed497c3fd8fd3545b49426d0b58ca22502c1895c | |
| parent | 3f00d57fffdf2708689bd75780cb0eeee26eedea (diff) | |
irq_remap: disable IRQ remapping if any IOAPIC lacks an IOMMU
commit 32ab31e01e2def6f48294d872d9bb42573aae00f upstream.
The ACPI tables in the Macbook Air 5,1 define a single IOAPIC with id 2,
but the only remapping unit described in the DMAR table matches id 0.
Interrupt remapping fails as a result, and the kernel panics with the
message "timer doesn't work through Interrupt-remapped IO-APIC."
To fix this, check each IOAPIC for a corresponding IOMMU. If an IOMMU is
not found, do not allow IRQ remapping to be enabled.
v2: Move check to parse_ioapics_under_ir(), raise log level to KERN_ERR,
and add FW_BUG to the log message
v3: Skip check if IOMMU doesn't support interrupt remapping and remove
existing check that the IOMMU count equals the IOAPIC count
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | drivers/iommu/intr_remapping.c | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/drivers/iommu/intr_remapping.c b/drivers/iommu/intr_remapping.c index 6777ca049471..73ca321f330a 100644 --- a/drivers/iommu/intr_remapping.c +++ b/drivers/iommu/intr_remapping.c @@ -752,6 +752,7 @@ int __init parse_ioapics_under_ir(void) { struct dmar_drhd_unit *drhd; int ir_supported = 0; + int ioapic_idx; for_each_drhd_unit(drhd) { struct intel_iommu *iommu = drhd->iommu; @@ -764,13 +765,20 @@ int __init parse_ioapics_under_ir(void) } } - if (ir_supported && ir_ioapic_num != nr_ioapics) { - printk(KERN_WARNING - "Not all IO-APIC's listed under remapping hardware\n"); - return -1; + if (!ir_supported) + return 0; + + for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++) { + int ioapic_id = mpc_ioapic_id(ioapic_idx); + if (!map_ioapic_to_ir(ioapic_id)) { + pr_err(FW_BUG "ioapic %d has no mapping iommu, " + "interrupt remapping will be disabled\n", + ioapic_id); + return -1; + } } - return ir_supported; + return 1; } int __init ir_dev_scope_init(void) |