[git pull] AMD IOMMU fixes for 3.0-rc2

[git pull] AMD IOMMU fixes for 3.0-rc2

[Joerg Roedel]

Hi Ingo,

The following changes since commit 59c5f46fbe01a00eedf54a23789634438bb80603:

  Linux 3.0-rc2 (2011-06-06 18:06:33 +0900)

are available in the git repository at:
  git://git.kernel.org/pub/scm/linux/kernel/git/joro/linux-2.6-iommu.git amd-iommu/fixes

Joerg Roedel (3):
      x86/amd-iommu: Fix 3 possible endless loops
      x86/amd-iommu: Use only per-device dma_ops
      x86/amd-iommu: Fix boot crash with hidden PCI devices

 arch/x86/kernel/amd_iommu.c      |   48 +++++++++++++++++++++++++++++++++++--
 arch/x86/kernel/amd_iommu_init.c |    8 +++---
 2 files changed, 49 insertions(+), 7 deletions(-)

These patches fix serious issues which were discovered recently like a
boot-stall and a boot crash when a device has an alias which does not exist a
pci_dev. Please pull.

	Joerg

[PATCH 1/3] x86/amd-iommu: Fix 3 possible endless loops

[Joerg Roedel]

The driver contains several loops counting on an u16 value
where the exit-condition is checked against variables that
can have values up to 0xffff. In this case the loops will
never exit. This patch fixed 3 such loops.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 arch/x86/kernel/amd_iommu_init.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c
index 9179c21..bfc8453 100644
--- a/arch/x86/kernel/amd_iommu_init.c
+++ b/arch/x86/kernel/amd_iommu_init.c
@@ -731,8 +731,8 @@ static void __init init_iommu_from_acpi(struct amd_iommu *iommu,
 {
 	u8 *p = (u8 *)h;
 	u8 *end = p, flags = 0;
-	u16 dev_i, devid = 0, devid_start = 0, devid_to = 0;
-	u32 ext_flags = 0;
+	u16 devid = 0, devid_start = 0, devid_to = 0;
+	u32 dev_i, ext_flags = 0;
 	bool alias = false;
 	struct ivhd_entry *e;
 
@@ -887,7 +887,7 @@ static void __init init_iommu_from_acpi(struct amd_iommu *iommu,
 /* Initializes the device->iommu mapping for the driver */
 static int __init init_iommu_devices(struct amd_iommu *iommu)
 {
-	u16 i;
+	u32 i;
 
 	for (i = iommu->first_device; i <= iommu->last_device; ++i)
 		set_iommu_for_device(iommu, i);
@@ -1177,7 +1177,7 @@ static int __init init_memory_definitions(struct acpi_table_header *table)
  */
 static void init_device_table(void)
 {
-	u16 devid;
+	u32 devid;
 
 	for (devid = 0; devid <= amd_iommu_last_bdf; ++devid) {
 		set_dev_entry_bit(devid, DEV_ENTRY_VALID);
-- 
1.7.4.1

[PATCH 2/3] x86/amd-iommu: Use only per-device dma_ops

[Joerg Roedel]

Unfortunatly there are systems where the AMD IOMMU does not
cover all devices. This breaks with the current driver as it
initializes the global dma_ops variable. This patch limits
the AMD IOMMU to the devices listed in the IVRS table fixing
DMA for devices not covered by the IOMMU.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 arch/x86/kernel/amd_iommu.c |   26 ++++++++++++++++++++++++--
 1 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index cd8cbeb..b2c309b 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -30,6 +30,7 @@
 #include <asm/proto.h>
 #include <asm/iommu.h>
 #include <asm/gart.h>
+#include <asm/dma.h>
 #include <asm/amd_iommu_proto.h>
 #include <asm/amd_iommu_types.h>
 #include <asm/amd_iommu.h>
@@ -2383,6 +2384,23 @@ static struct dma_map_ops amd_iommu_dma_ops = {
 	.dma_supported = amd_iommu_dma_supported,
 };
 
+static unsigned device_dma_ops_init(void)
+{
+	struct pci_dev *pdev = NULL;
+	unsigned unhandled = 0;
+
+	for_each_pci_dev(pdev) {
+		if (!check_device(&pdev->dev)) {
+			unhandled += 1;
+			continue;
+		}
+
+		pdev->dev.archdata.dma_ops = &amd_iommu_dma_ops;
+	}
+
+	return unhandled;
+}
+
 /*
  * The function which clues the AMD IOMMU driver into dma_ops.
  */
@@ -2395,7 +2413,7 @@ void __init amd_iommu_init_api(void)
 int __init amd_iommu_init_dma_ops(void)
 {
 	struct amd_iommu *iommu;
-	int ret;
+	int ret, unhandled;
 
 	/*
 	 * first allocate a default protection domain for every IOMMU we
@@ -2421,7 +2439,11 @@ int __init amd_iommu_init_dma_ops(void)
 	swiotlb = 0;
 
 	/* Make the driver finally visible to the drivers */
-	dma_ops = &amd_iommu_dma_ops;
+	unhandled = device_dma_ops_init();
+	if (unhandled && max_pfn > MAX_DMA32_PFN) {
+		/* There are unhandled devices - initialize swiotlb for them */
+		swiotlb = 1;
+	}
 
 	amd_iommu_stats_init();
 
-- 
1.7.4.1

[PATCH 3/3] x86/amd-iommu: Fix boot crash with hidden PCI devices

[Joerg Roedel]

Some PCIe cards ship with a PCI-PCIe bridge which is not
visible as a PCI device in Linux. But the device-id of the
bridge is present in the IOMMU tables which causes a boot
crash in the IOMMU driver.
This patch fixes by removing these cards from the IOMMU
handling. This is a pure -stable fix, a real fix to handle
this situation appriatly will follow for the next merge
window.

Cc: stable@kernel.org	# > 2.6.32
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 arch/x86/kernel/amd_iommu.c |   22 +++++++++++++++++++++-
 1 files changed, 21 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index b2c309b..7c3a95e 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -155,6 +155,10 @@ static int iommu_init_device(struct device *dev)
 	pdev = pci_get_bus_and_slot(PCI_BUS(alias), alias & 0xff);
 	if (pdev)
 		dev_data->alias = &pdev->dev;
+	else {
+		kfree(dev_data);
+		return -ENOTSUPP;
+	}
 
 	atomic_set(&dev_data->bind, 0);
 
@@ -164,6 +168,20 @@ static int iommu_init_device(struct device *dev)
 	return 0;
 }
 
+static void iommu_ignore_device(struct device *dev)
+{
+	u16 devid, alias;
+
+	devid = get_device_id(dev);
+	alias = amd_iommu_alias_table[devid];
+
+	memset(&amd_iommu_dev_table[devid], 0, sizeof(struct dev_table_entry));
+	memset(&amd_iommu_dev_table[alias], 0, sizeof(struct dev_table_entry));
+
+	amd_iommu_rlookup_table[devid] = NULL;
+	amd_iommu_rlookup_table[alias] = NULL;
+}
+
 static void iommu_uninit_device(struct device *dev)
 {
 	kfree(dev->archdata.iommu);
@@ -193,7 +211,9 @@ int __init amd_iommu_init_devices(void)
 			continue;
 
 		ret = iommu_init_device(&pdev->dev);
-		if (ret)
+		if (ret == -ENOTSUPP)
+			iommu_ignore_device(&pdev->dev);
+		else if (ret)
 			goto out_free;
 	}
 
-- 
1.7.4.1

Re: [git pull] AMD IOMMU fixes for 3.0-rc2

[Ingo Molnar]

* Joerg Roedel <joerg.roedel@amd.com> wrote:

> Hi Ingo,
> 
> The following changes since commit 59c5f46fbe01a00eedf54a23789634438bb80603:
> 
>   Linux 3.0-rc2 (2011-06-06 18:06:33 +0900)
> 
> are available in the git repository at:
>   git://git.kernel.org/pub/scm/linux/kernel/git/joro/linux-2.6-iommu.git amd-iommu/fixes
> 
> Joerg Roedel (3):
>       x86/amd-iommu: Fix 3 possible endless loops
>       x86/amd-iommu: Use only per-device dma_ops
>       x86/amd-iommu: Fix boot crash with hidden PCI devices
> 
>  arch/x86/kernel/amd_iommu.c      |   48 +++++++++++++++++++++++++++++++++++--
>  arch/x86/kernel/amd_iommu_init.c |    8 +++---
>  2 files changed, 49 insertions(+), 7 deletions(-)
> 
> These patches fix serious issues which were discovered recently like a
> boot-stall and a boot crash when a device has an alias which does not exist a
> pci_dev. Please pull.

Pulled, thanks a lot Joerg!

	Ingo