[patch 2/8] intr_remap: call dmar_dev_scope_init() explicitly

Suresh Siddha
2011-08-24T00:52:28Z

[-- Attachment #1: init_dev_scope_from_intr_remap.patch --]
[-- Type: text/plain, Size: 3346 bytes --]

Both DMA-remapping aswell as Interrupt-remapping depend on the dmar dev scope
to be initialized. When both DMA and IRQ-remapping are enabled, we depend
on DMA-remapping init code to call dmar_dev_scope_init(). This resulted
in not doing this init when DMA-remapping was turned off but
interrupt-remapping turned on in the kernel config.

This caused interrupt routing to break with CONFIG_INTR_REMAP=y
and CONFIG_DMAR=n.

This issue was introduced by this commit:

commit 9d5ce73a64be2be8112147a3e0b551ad9cd1247b
Author: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Date: Tue Nov 10 19:46:16 2009 +0900

x86: intel-iommu: Convert detect_intel_iommu to use iommu_init hook

Fix this by calling dmar_dev_scope_init() explicitly from the interrupt
remapping code too.

Reported-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
---
drivers/iommu/dmar.c | 15 ++++++++++++---
drivers/iommu/intel-iommu.c | 6 +-----
drivers/iommu/intr_remapping.c | 9 +++++++++
3 files changed, 22 insertions(+), 8 deletions(-)

Index: tree/drivers/iommu/dmar.c
===================================================================
--- tree.orig/drivers/iommu/dmar.c
+++ tree/drivers/iommu/dmar.c
@@ -557,13 +557,17 @@ dmar_find_matched_drhd_unit(struct pci_d

int __init dmar_dev_scope_init(void)
{
+ static int dmar_dev_scope_initialized;
struct dmar_drhd_unit *drhd, *drhd_n;
int ret = -ENODEV;

+ if (dmar_dev_scope_initialized)
+ return dmar_dev_scope_initialized;
+
list_for_each_entry_safe(drhd, drhd_n, &dmar_drhd_units, list) {
ret = dmar_parse_dev(drhd);
if (ret)
- return ret;
+ goto fail;
}

#ifdef CONFIG_DMAR
@@ -574,17 +578,22 @@ int __init dmar_dev_scope_init(void)
list_for_each_entry_safe(rmrr, rmrr_n, &dmar_rmrr_units, list) {
ret = rmrr_parse_dev(rmrr);
if (ret)
- return ret;
+ goto fail;
}

list_for_each_entry_safe(atsr, atsr_n, &dmar_atsr_units, list) {
ret = atsr_parse_dev(atsr);
if (ret)
- return ret;
+ goto fail;
}
}
#endif

+ dmar_dev_scope_initialized = 1;
+ return 0;
+
+fail:
+ dmar_dev_scope_initialized = ret;
return ret;
}

Index: tree/drivers/iommu/intr_remapping.c
===================================================================
--- tree.orig/drivers/iommu/intr_remapping.c
+++ tree/drivers/iommu/intr_remapping.c
@@ -773,6 +773,15 @@ int __init parse_ioapics_under_ir(void)
return ir_supported;
}

+int ir_dev_scope_init(void)
+{
+ if (!intr_remapping_enabled)
+ return 0;
+
+ return dmar_dev_scope_init();
+}
+rootfs_initcall(ir_dev_scope_init);
+
void disable_intr_remapping(void)
{
struct dmar_drhd_unit *drhd;
Index: tree/drivers/iommu/intel-iommu.c
===================================================================
--- tree.orig/drivers/iommu/intel-iommu.c
+++ tree/drivers/iommu/intel-iommu.c
@@ -3439,16 +3439,12 @@ int __init intel_iommu_init(void)
return -ENODEV;
}

- if (dmar_dev_scope_init()) {
+ if (dmar_dev_scope_init() < 0) {
if (force_on)
panic("tboot: Failed to initialize DMAR device scope\n");
return -ENODEV;
}

- /*
- * Check the need for DMA-remapping initialization now.
- * Above initialization will also be used by Interrupt-remapping.
- */
if (no_iommu || dmar_disabled)
return -ENODEV;