From 38e45d02ea9f194b89d6bf41e52ccafc8e2c2b47 Mon Sep 17 00:00:00 2001
From: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Date: Tue, 23 Feb 2016 13:03:30 +0100
Subject: [PATCH 1/4] iommu/amd: Fix boot warning when device 00:00.0 is not
iommu covered
The setup code for the performance counters in the AMD IOMMU driver
tests whether the counters can be written. It tests to setup a counter
for device 00:00.0, which fails on systems where this particular device
is not covered by the IOMMU.
Fix this by not relying on device 00:00.0 but only on the IOMMU being
present.
Cc: stable@vger.kernel.org
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/amd_iommu_init.c | 34 ++++++++++++++++++++++------------
1 file changed, 22 insertions(+), 12 deletions(-)
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 013bdfff2d4d0..d06a6d9edbcad 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -228,6 +228,10 @@ static int amd_iommu_enable_interrupts(void);
static int __init iommu_go_to_state(enum iommu_init_state state);
static void init_device_table_dma(void);
+static int iommu_pc_get_set_reg_val(struct amd_iommu *iommu,
+ u8 bank, u8 cntr, u8 fxn,
+ u64 *value, bool is_write);
+
static inline void update_last_devid(u16 devid)
{
if (devid > amd_iommu_last_bdf)
@@ -1142,8 +1146,8 @@ static void init_iommu_perf_ctr(struct amd_iommu *iommu)
amd_iommu_pc_present = true;
/* Check if the performance counters can be written to */
- if ((0 != amd_iommu_pc_get_set_reg_val(0, 0, 0, 0, &val, true)) ||
- (0 != amd_iommu_pc_get_set_reg_val(0, 0, 0, 0, &val2, false)) ||
+ if ((0 != iommu_pc_get_set_reg_val(iommu, 0, 0, 0, &val, true)) ||
+ (0 != iommu_pc_get_set_reg_val(iommu, 0, 0, 0, &val2, false)) ||
(val != val2)) {
pr_err("AMD-Vi: Unable to write to IOMMU perf counter.\n");
amd_iommu_pc_present = false;
@@ -2283,22 +2287,15 @@ u8 amd_iommu_pc_get_max_counters(u16 devid)
}
EXPORT_SYMBOL(amd_iommu_pc_get_max_counters);
-int amd_iommu_pc_get_set_reg_val(u16 devid, u8 bank, u8 cntr, u8 fxn,
+static int iommu_pc_get_set_reg_val(struct amd_iommu *iommu,
+ u8 bank, u8 cntr, u8 fxn,
u64 *value, bool is_write)
{
- struct amd_iommu *iommu;
u32 offset;
u32 max_offset_lim;
- /* Make sure the IOMMU PC resource is available */
- if (!amd_iommu_pc_present)
- return -ENODEV;
-
- /* Locate the iommu associated with the device ID */
- iommu = amd_iommu_rlookup_table[devid];
-
/* Check for valid iommu and pc register indexing */
- if (WARN_ON((iommu == NULL) || (fxn > 0x28) || (fxn & 7)))
+ if (WARN_ON((fxn > 0x28) || (fxn & 7)))
return -ENODEV;
offset = (u32)(((0x40|bank) << 12) | (cntr << 8) | fxn);
@@ -2322,3 +2319,16 @@ int amd_iommu_pc_get_set_reg_val(u16 devid, u8 bank, u8 cntr, u8 fxn,
return 0;
}
EXPORT_SYMBOL(amd_iommu_pc_get_set_reg_val);
+
+int amd_iommu_pc_get_set_reg_val(u16 devid, u8 bank, u8 cntr, u8 fxn,
+ u64 *value, bool is_write)
+{
+ struct amd_iommu *iommu = amd_iommu_rlookup_table[devid];
+
+ /* Make sure the IOMMU PC resource is available */
+ if (!amd_iommu_pc_present || iommu == NULL)
+ return -ENODEV;
+
+ return iommu_pc_get_set_reg_val(iommu, bank, cntr, fxn,
+ value, is_write);
+}
From 358875fd52ab8f00f66328cbf1a1d2486f265829 Mon Sep 17 00:00:00 2001
From: Jay Cornwall <jay@jcornwall.me>
Date: Wed, 10 Feb 2016 15:48:01 -0600
Subject: [PATCH 2/4] iommu/amd: Apply workaround for ATS write permission
check
The AMD Family 15h Models 30h-3Fh (Kaveri) BIOS and Kernel Developer's
Guide omitted part of the BIOS IOMMU L2 register setup specification.
Without this setup the IOMMU L2 does not fully respect write permissions
when handling an ATS translation request.
The IOMMU L2 will set PTE dirty bit when handling an ATS translation with
write permission request, even when PTE RW bit is clear. This may occur by
direct translation (which would cause a PPR) or by prefetch request from
the ATC.
This is observed in practice when the IOMMU L2 modifies a PTE which maps a
pagecache page. The ext4 filesystem driver BUGs when asked to writeback
these (non-modified) pages.
Enable ATS write permission check in the Kaveri IOMMU L2 if BIOS has not.
Signed-off-by: Jay Cornwall <jay@jcornwall.me>
Cc: <stable@vger.kernel.org> # v3.19+
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/amd_iommu_init.c | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index d06a6d9edbcad..bf4959f4225bd 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -1019,6 +1019,34 @@ static void amd_iommu_erratum_746_workaround(struct amd_iommu *iommu)
pci_write_config_dword(iommu->dev, 0xf0, 0x90);
}
+/*
+ * Family15h Model 30h-3fh (IOMMU Mishandles ATS Write Permission)
+ * Workaround:
+ * BIOS should enable ATS write permission check by setting
+ * L2_DEBUG_3[AtsIgnoreIWDis](D0F2xF4_x47[0]) = 1b
+ */
+static void amd_iommu_ats_write_check_workaround(struct amd_iommu *iommu)
+{
+ u32 value;
+
+ if ((boot_cpu_data.x86 != 0x15) ||
+ (boot_cpu_data.x86_model < 0x30) ||
+ (boot_cpu_data.x86_model > 0x3f))
+ return;
+
+ /* Test L2_DEBUG_3[AtsIgnoreIWDis] == 1 */
+ value = iommu_read_l2(iommu, 0x47);
+
+ if (value & BIT(0))
+ return;
+
+ /* Set L2_DEBUG_3[AtsIgnoreIWDis] = 1 */
+ iommu_write_l2(iommu, 0x47, value | BIT(0));
+
+ pr_info("AMD-Vi: Applying ATS write check workaround for IOMMU at %s\n",
+ dev_name(&iommu->dev->dev));
+}
+
/*
* This function clues the initialization function for one IOMMU
* together and also allocates the command buffer and programs the
@@ -1288,6 +1316,7 @@ static int iommu_init_pci(struct amd_iommu *iommu)
}
amd_iommu_erratum_746_workaround(iommu);
+ amd_iommu_ats_write_check_workaround(iommu);
iommu->iommu_dev = iommu_device_create(&iommu->dev->dev, iommu,
amd_iommu_groups, "ivhd%d",
From b6809ee573cc2f8de97f7c8f45eacc5db1129060 Mon Sep 17 00:00:00 2001
From: Joerg Roedel <jroedel@suse.de>
Date: Fri, 26 Feb 2016 16:48:59 +0100
Subject: [PATCH 3/4] iommu/amd: Detach device from domain before removal
Detach the device that is about to be removed from its
domain (if it has one) to clear any related state like DTE
entry and device's ATS state.
Reported-by: Kelly Zytaruk <Kelly.Zytaruk@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/amd_iommu.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index e5e223938eecc..374c129219ef0 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -114,6 +114,7 @@ struct kmem_cache *amd_iommu_irq_cache;
static void update_domain(struct protection_domain *domain);
static int protection_domain_init(struct protection_domain *domain);
+static void detach_device(struct device *dev);
/*
* For dynamic growth the aperture size is split into ranges of 128MB of
@@ -384,6 +385,9 @@ static void iommu_uninit_device(struct device *dev)
if (!dev_data)
return;
+ if (dev_data->domain)
+ detach_device(dev);
+
iommu_device_unlink(amd_iommu_rlookup_table[dev_data->devid]->iommu_dev,
dev);
From e6a8c9b337eed56eb481e1b4dd2180c25a1e5310 Mon Sep 17 00:00:00 2001
From: Joerg Roedel <jroedel@suse.de>
Date: Mon, 29 Feb 2016 23:49:47 +0100
Subject: [PATCH 4/4] iommu/vt-d: Use BUS_NOTIFY_REMOVED_DEVICE in hotplug path
In the PCI hotplug path of the Intel IOMMU driver, replace
the usage of the BUS_NOTIFY_DEL_DEVICE notifier, which is
executed before the driver is unbound from the device, with
BUS_NOTIFY_REMOVED_DEVICE, which runs after that.
This fixes a kernel BUG being triggered in the VT-d code
when the device driver tries to unmap DMA buffers and the
VT-d driver already destroyed all mappings.
Reported-by: Stefani Seibold <stefani@seibold.net>
Cc: stable@vger.kernel.org # v4.3+
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/dmar.c | 5 +++--
drivers/iommu/intel-iommu.c | 4 ++--
2 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index fb092f3f11cb3..8ffd7568fc919 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -329,7 +329,8 @@ static int dmar_pci_bus_notifier(struct notifier_block *nb,
/* Only care about add/remove events for physical functions */
if (pdev->is_virtfn)
return NOTIFY_DONE;
- if (action != BUS_NOTIFY_ADD_DEVICE && action != BUS_NOTIFY_DEL_DEVICE)
+ if (action != BUS_NOTIFY_ADD_DEVICE &&
+ action != BUS_NOTIFY_REMOVED_DEVICE)
return NOTIFY_DONE;
info = dmar_alloc_pci_notify_info(pdev, action);
@@ -339,7 +340,7 @@ static int dmar_pci_bus_notifier(struct notifier_block *nb,
down_write(&dmar_global_lock);
if (action == BUS_NOTIFY_ADD_DEVICE)
dmar_pci_bus_add_dev(info);
- else if (action == BUS_NOTIFY_DEL_DEVICE)
+ else if (action == BUS_NOTIFY_REMOVED_DEVICE)
dmar_pci_bus_del_dev(info);
up_write(&dmar_global_lock);
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 986a53e3eb96b..a2e1b7f14df29 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -4367,7 +4367,7 @@ int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
rmrru->devices_cnt);
if(ret < 0)
return ret;
- } else if (info->event == BUS_NOTIFY_DEL_DEVICE) {
+ } else if (info->event == BUS_NOTIFY_REMOVED_DEVICE) {
dmar_remove_dev_scope(info, rmrr->segment,
rmrru->devices, rmrru->devices_cnt);
}
@@ -4387,7 +4387,7 @@ int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
break;
else if(ret < 0)
return ret;
- } else if (info->event == BUS_NOTIFY_DEL_DEVICE) {
+ } else if (info->event == BUS_NOTIFY_REMOVED_DEVICE) {
if (dmar_remove_dev_scope(info, atsr->segment,
atsru->devices, atsru->devices_cnt))
break;