Re: [PATCH v2 00/21] Allow compile-testing NO_DMA (drivers)
On Fri, Mar 16, 2018 at 8:51 AM, Geert Uytterhoeven wrote: > Hi all, > > If NO_DMA=y, get_dma_ops() returns a reference to the non-existing > symbol bad_dma_ops, thus causing a link failure if it is ever used. > > The intention of this is twofold: > 1. To catch users of the DMA API on systems that do no support the DMA > mapping API, > 2. To avoid building drivers that cannot work on such systems anyway. > > However, the disadvantage is that we have to keep on adding dependencies > on HAS_DMA all over the place. > > Thanks to the COMPILE_TEST symbol, lots of drivers now depend on one or > more platform dependencies (that imply HAS_DMA) || COMPILE_TEST, thus > already covering intention #2. Having to add an explicit dependency on > HAS_DMA here is cumbersome, and hinders compile-testing. The same can be said for CONFIG_IOMEM and CONFIG_OF. Any plans to remove those too? CONFIG_IOMEM is mostly just a !CONFIG_UM option. Rob ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
[PATCH v2 2/2] iommu/amd: Add basic debugfs infrastructure for AMD IOMMU
Implement a skeleton framework for debugfs support in the
AMD IOMMU.
Signed-off-by: Gary R Hook
---
drivers/iommu/Makefile|1 +
drivers/iommu/amd_iommu_debugfs.c | 45 +
drivers/iommu/amd_iommu_init.c|7 --
drivers/iommu/amd_iommu_proto.h |8 ++-
drivers/iommu/amd_iommu_types.h |3 ++
5 files changed, 61 insertions(+), 3 deletions(-)
create mode 100644 drivers/iommu/amd_iommu_debugfs.c
diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index 5eb1121d54b9..0ca250f626d9 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_IOMMU_IOVA) += iova.o
obj-$(CONFIG_OF_IOMMU) += of_iommu.o
obj-$(CONFIG_MSM_IOMMU) += msm_iommu.o
obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o amd_iommu_init.o
+obj-$(CONFIG_IOMMU_DEBUG) += amd_iommu_debugfs.o
obj-$(CONFIG_AMD_IOMMU_V2) += amd_iommu_v2.o
obj-$(CONFIG_ARM_SMMU) += arm-smmu.o
obj-$(CONFIG_ARM_SMMU_V3) += arm-smmu-v3.o
diff --git a/drivers/iommu/amd_iommu_debugfs.c
b/drivers/iommu/amd_iommu_debugfs.c
new file mode 100644
index ..282100a655b3
--- /dev/null
+++ b/drivers/iommu/amd_iommu_debugfs.c
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD IOMMU driver
+ *
+ * Copyright (C) 2018 Advanced Micro Devices, Inc.
+ *
+ * Author: Gary R Hook
+ */
+
+#include
+#include
+#include
+#include "amd_iommu_proto.h"
+#include "amd_iommu_types.h"
+
+static struct dentry *amd_iommu_debugfs;
+static DEFINE_MUTEX(amd_iommu_debugfs_lock);
+
+#defineMAX_NAME_LEN20
+
+void amd_iommu_debugfs_setup(struct amd_iommu *iommu)
+{
+ char name[MAX_NAME_LEN + 1];
+ struct dentry *d_top;
+
+ if (!debugfs_initialized())
+ return;
+
+ mutex_lock(&amd_iommu_debugfs_lock);
+ if (!amd_iommu_debugfs) {
+ d_top = iommu_debugfs_setup();
+ if (d_top)
+ amd_iommu_debugfs = debugfs_create_dir("amd", d_top);
+ }
+ mutex_unlock(&amd_iommu_debugfs_lock);
+ if (amd_iommu_debugfs) {
+ snprintf(name, MAX_NAME_LEN, "iommu%02d", iommu->index);
+ iommu->debugfs = debugfs_create_dir(name,
+ amd_iommu_debugfs);
+ if (!iommu->debugfs) {
+ debugfs_remove_recursive(amd_iommu_debugfs);
+ amd_iommu_debugfs = NULL;
+ }
+ }
+}
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 6fe2d0346073..43856c7f4ea1 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -89,6 +89,7 @@
#define ACPI_DEVFLAG_ATSDIS 0x1000
#define LOOP_TIMEOUT 10
+
/*
* ACPI table definitions
*
@@ -2720,6 +2721,7 @@ int __init amd_iommu_enable_faulting(void)
*/
static int __init amd_iommu_init(void)
{
+ struct amd_iommu *iommu;
int ret;
ret = iommu_go_to_state(IOMMU_INITIALIZED);
@@ -2729,14 +2731,15 @@ static int __init amd_iommu_init(void)
disable_iommus();
free_iommu_resources();
} else {
- struct amd_iommu *iommu;
-
uninit_device_table_dma();
for_each_iommu(iommu)
iommu_flush_all_caches(iommu);
}
}
+ for_each_iommu(iommu)
+ amd_iommu_debugfs_setup(iommu);
+
return ret;
}
diff --git a/drivers/iommu/amd_iommu_proto.h b/drivers/iommu/amd_iommu_proto.h
index 640c286a0ab9..1cfaae28c2cd 100644
--- a/drivers/iommu/amd_iommu_proto.h
+++ b/drivers/iommu/amd_iommu_proto.h
@@ -33,6 +33,12 @@ extern void amd_iommu_uninit_devices(void);
extern void amd_iommu_init_notifier(void);
extern int amd_iommu_init_api(void);
+#ifdef CONFIG_IOMMU_DEBUG
+void amd_iommu_debugfs_setup(struct amd_iommu *iommu);
+#else
+static inline void amd_iommu_debugfs_setup(struct amd_iommu *iommu) {}
+#endif
+
/* Needed for interrupt remapping */
extern int amd_iommu_prepare(void);
extern int amd_iommu_enable(void);
@@ -58,7 +64,7 @@ extern int amd_iommu_domain_clear_gcr3(struct iommu_domain
*dom, int pasid);
extern struct iommu_domain *amd_iommu_get_v2_domain(struct pci_dev *pdev);
#ifdef CONFIG_IRQ_REMAP
-extern int amd_iommu_create_irq_domain(struct amd_iommu *iommu);
+int amd_iommu_create_irq_domain(struct amd_iommu *iommu);
#else
static inline int amd_iommu_create_irq_domain(struct amd_iommu *iommu)
{
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index f6b24c7d8b70..43c52797810e 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -591,6 +591,9 @@ struct amd_iommu {
u32 flags;
volatile u64 __aligned(8) cmd_sem;
+
+ /* DebugFS Info */
+ struct dentry *debugfs;
};
static inline struct amd_iommu *dev_to_am
[PATCH v2 1/2] iommu - Enable debugfs exposure of the IOMMU
Provide base enablement for using debugfs to expose internal data of
an IOMMU driver. When called, create the /sys/kernel/debug/iommu
directory. Emit a strong warning at boot time to indicate that this
feature is enabled.
This patch adds a top-level function that will create the (above)
directory, under which a driver may create a hw-specific directory for
its use. The function
iommu_debugfs_setup()
returns a pointer to the new dentry structure created for
/sys/kernel/debug/iommu, or NULL in the event of a failure. An IOMMU
driver should call this function first, and then create a directory
beneath it. A driver implementation might look something like:
static struct dentry *my_debugfs;
struct dentry *d_top;
if (!my_debugfs) {
d_top = iommu_debugfs_setup();
if (d_top)
my_debugfs = debugfs_create_dir("vendor", d_top);
}
Since the IOMMU driver can not be removed from the running system, this
patch only provides an "on" function.
Signed-off-by: Gary R Hook
---
drivers/iommu/Kconfig | 11
drivers/iommu/Makefile|1 +
drivers/iommu/iommu-debugfs.c | 58 +
include/linux/iommu.h |4 +++
4 files changed, 74 insertions(+)
create mode 100644 drivers/iommu/iommu-debugfs.c
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index f3a21343e636..c1e39dabfec2 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -60,6 +60,17 @@ config IOMMU_IO_PGTABLE_ARMV7S_SELFTEST
endmenu
+config IOMMU_DEBUG
+ bool "Enable IOMMU internals in DebugFS"
+ depends on DEBUG_FS
+ default n
+ help
+ Allows exposure of IOMMU device internals. This option enables
+ the use of debugfs by IOMMU drivers as required. Devices can,
+ at initialization time, cause the IOMMU code to create a top-level
+ debug/iommu directory, and then populate a subdirectory with
+ entries as required.
+
config IOMMU_IOVA
tristate
diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index 1fb695854809..5eb1121d54b9 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -2,6 +2,7 @@
obj-$(CONFIG_IOMMU_API) += iommu.o
obj-$(CONFIG_IOMMU_API) += iommu-traces.o
obj-$(CONFIG_IOMMU_API) += iommu-sysfs.o
+obj-$(CONFIG_IOMMU_DEBUG) += iommu-debugfs.o
obj-$(CONFIG_IOMMU_DMA) += dma-iommu.o
obj-$(CONFIG_IOMMU_IO_PGTABLE) += io-pgtable.o
obj-$(CONFIG_IOMMU_IO_PGTABLE_ARMV7S) += io-pgtable-arm-v7s.o
diff --git a/drivers/iommu/iommu-debugfs.c b/drivers/iommu/iommu-debugfs.c
new file mode 100644
index ..add6f95120e4
--- /dev/null
+++ b/drivers/iommu/iommu-debugfs.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IOMMU driver
+ *
+ * Copyright (C) 2018 Advanced Micro Devices, Inc.
+ *
+ * Author: Gary R Hook
+ */
+
+#include
+#include
+#include
+
+static struct dentry *iommu_debugfs_dir;
+
+/*
+ * Provide base enablement for using debugfs to expose internal data of an
+ * IOMMU driver. When called, create the /sys/kernel/debug/iommu directory.
+ *
+ * Emit a strong warning at boot time to indicate that this feature is
+ * enabled.
+ *
+ * This top-level function that will create the (above) directory, under a
+ * driver may create a hw-specific directory for its use. The function
+ *
+ * iommu_debugfs_setup()
+ *
+ * returns a pointer to the new dentry structure created for
+ * /sys/kernel/debug/iommu, or NULL in the event of a failure. An IOMMU
+ * driver should call this function first, and then create a directory
+ * beneath it. A driver implementation might look something like:
+ *
+ * static struct dentry *my_debugfs;
+ *
+ *struct dentry *d_top;
+ *if (!my_debugfs) {
+ *d_top = iommu_debugfs_setup();
+ *if (d_top)
+ *my_debugfs = debugfs_create_dir("vendor", d_top);
+ *}
+ *
+ * Since the IOMMU driver can not be removed from the running system, there
+ * is no need for an "off" function.
+ */
+struct dentry *iommu_debugfs_setup(void)
+{
+ if (!debugfs_initialized())
+ return NULL;
+
+ if (!iommu_debugfs_dir)
+ iommu_debugfs_dir = debugfs_create_dir("iommu", NULL);
+
+ if (iommu_debugfs_dir)
+ pr_warn("WARNING: IOMMU DEBUGFS SUPPORT HAS BEEN ENABLED IN
THIS KERNEL\n");
+
+ return iommu_debugfs_dir;
+}
+EXPORT_SYMBOL_GPL(iommu_debugfs_setup);
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 41b8c5757859..3dd2e73d31c4 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -412,6 +412,10 @@ void iommu_fwspec_free(struct device *dev);
int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids);
const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode);
+#ifdef CONFIG_IOMMU_DEBUG
+struct dentry *iommu_debugfs_setup(void);
+#endif
+
#else /* CONFIG_IOMMU_API */
struct iommu_ops {};
[PATCH v2 0/2] Base enablement of IOMMU debugfs support
These patches create a top-level function to create a debugfs directory for the IOMMU, under which drivers may create and populate-specific directories for their device internals. Patch 1: general IOMMU enablement Patch 2: basic AMD enablement to demonstrate linkage with patch 1 Introduce a new Kconfig parameter IOMMU_DEBUG to globally allow or disallow debugfs code to be built. Changes since v1: - Remove debug cruft - Remove cruft produced by design change - Change the lock to a mutex - Coding style fixes - Add a comment to document the framework --- Gary R Hook (2): iommu - Enable debugfs exposure of the IOMMU iommu/amd: Add basic debugfs infrastructure for AMD IOMMU drivers/iommu/Kconfig | 11 +++ drivers/iommu/Makefile|2 + drivers/iommu/amd_iommu_debugfs.c | 45 + drivers/iommu/amd_iommu_init.c|7 +++- drivers/iommu/amd_iommu_proto.h |8 - drivers/iommu/amd_iommu_types.h |3 ++ drivers/iommu/iommu-debugfs.c | 58 + include/linux/iommu.h |4 +++ 8 files changed, 135 insertions(+), 3 deletions(-) create mode 100644 drivers/iommu/amd_iommu_debugfs.c create mode 100644 drivers/iommu/iommu-debugfs.c -- Signature ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
Re: [PATCH] iommu/vt-d: fix usage of force parameter in intel_ir_reconfigure_irte()
On 3/6/2018 5:39 PM, Jagannathan Raman wrote:
It was noticed that the IRTE configured for guest OS kernel
was over-written while the guest was running. As a result,
vt-d Posted Interrupts configured for the guest are not being
delivered directly, and instead bounces off the host. Every
interrupt delivery takes a VM Exit.
It was noticed that the following stack is doing the over-write:
[ 147.463177] modify_irte+0x171/0x1f0
[ 147.463405] intel_ir_set_affinity+0x5c/0x80
[ 147.463641] msi_domain_set_affinity+0x32/0x90
[ 147.463881] irq_do_set_affinity+0x37/0xd0
[ 147.464125] irq_set_affinity_locked+0x9d/0xb0
[ 147.464374] __irq_set_affinity+0x42/0x70
[ 147.464627] write_irq_affinity.isra.5+0xe1/0x110
[ 147.464895] proc_reg_write+0x38/0x70
[ 147.465150] __vfs_write+0x36/0x180
[ 147.465408] ? handle_mm_fault+0xdf/0x200
[ 147.465671] ? _cond_resched+0x15/0x30
[ 147.465936] vfs_write+0xad/0x1a0
[ 147.466204] SyS_write+0x52/0xc0
[ 147.466472] do_syscall_64+0x74/0x1a0
[ 147.466744] entry_SYSCALL_64_after_hwframe+0x3d/0xa2
reversing the sense of force check in intel_ir_reconfigure_irte()
restores proper posted interrupt functionality
Signed-off-by: Jagannathan Raman
---
Hi Thomas,
I noticed that you added intel_ir_reconfigure_irte() with the
following commit:
d491bdff888e ("iommu/vt-d: Reevaluate vector configuration on
activate()")
Could you please confirm the usage of "force" parameter in
intel_ir_reconfigure_irte()?
drivers/iommu/intel_irq_remapping.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/intel_irq_remapping.c
b/drivers/iommu/intel_irq_remapping.c
index 66f69af..3062a15 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -1136,7 +1136,7 @@ static void intel_ir_reconfigure_irte(struct irq_data
*irqd, bool force)
irte->dest_id = IRTE_DEST(cfg->dest_apicid);
/* Update the hardware only if the interrupt is in remapped mode. */
- if (!force || ir_data->irq_2_iommu.mode == IRQ_REMAPPING)
+ if (force || ir_data->irq_2_iommu.mode == IRQ_REMAPPING)
modify_irte(&ir_data->irq_2_iommu, irte);
}
*ping*
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Re: [PATCH] iommu: rockchip: fix building without CONFIG_OF
Hi Arnd,
On 04/04/18 11:23, Arnd Bergmann wrote:
We get a build error when compiling the iommu driver without CONFIG_OF:
drivers/iommu/rockchip-iommu.c: In function 'rk_iommu_of_xlate':
drivers/iommu/rockchip-iommu.c:1101:2: error: implicit declaration of function
'of_dev_put'; did you mean 'of_node_put'?
[-Werror=implicit-function-declaration]
This replaces the of_dev_put() with the equivalent platform_device_put(),
and adds an error check for of_find_device_by_node() returning NULL,
which seems to be appropriate here given that we pass the device into
platform_get_drvdata() next, and that of_find_device_by_node() might
theoretically return a NULL pointer.
Fixes: 5fd577c3eac3 ("iommu/rockchip: Use OF_IOMMU to attach devices
automatically")
Signed-off-by: Arnd Bergmann
---
This warning appears to only have been introduced in linux-next after
the merge window opened.
---
drivers/iommu/rockchip-iommu.c | 6 +-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index 5fc8656c60f9..fe9c9cc1a9d4 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -1094,11 +1094,15 @@ static int rk_iommu_of_xlate(struct device *dev,
return -ENOMEM;
iommu_dev = of_find_device_by_node(args->np);
+ if (!iommu_dev) {
Actually, though the logic is perhaps a bit subtle, this cannot
reasonably happen - .of_xlate is only called via a set of iommu_ops
associated with the IOMMU node (args->np here); those ops are only
registered for the given node at the end of rk_iommu_probe(), by which
point the IOMMU device exists and is otherwise successfully probed, so
the platform bus lookup should never be able to fail.
+ kfree(data);
+ return -ENODEV;
+ }
data->iommu = platform_get_drvdata(iommu_dev);
dev->archdata.iommu = data;
- of_dev_put(iommu_dev);
+ platform_device_put(iommu_dev);
This bit looks reasonable, thanks for the fix.
Robin.
return 0;
}
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Re: [PATCH] iommu: rockchip: fix building without CONFIG_OF
Hi Amd,
Thanks for your patch.
On 04/04/2018 06:23 PM, Arnd Bergmann wrote:
We get a build error when compiling the iommu driver without CONFIG_OF:
drivers/iommu/rockchip-iommu.c: In function 'rk_iommu_of_xlate':
drivers/iommu/rockchip-iommu.c:1101:2: error: implicit declaration of function
'of_dev_put'; did you mean 'of_node_put'?
[-Werror=implicit-function-declaration]
oops, didn't notice that.
and checking other iommu drivers which call of_find_device_by_node()
too, seems they didn't put() it? maybe we should fix them too
This replaces the of_dev_put() with the equivalent platform_device_put(),
and adds an error check for of_find_device_by_node() returning NULL,
which seems to be appropriate here given that we pass the device into
platform_get_drvdata() next, and that of_find_device_by_node() might
theoretically return a NULL pointer.
hmm, i thought the of_iommu_xlate() checked that before calling us:
static int of_iommu_xlate(struct device *dev,
struct of_phandle_args *iommu_spec)
{
...
if ((ops && !ops->of_xlate) ||
!of_device_is_available(iommu_spec->np) ||
(!ops && !of_iommu_driver_present(iommu_spec->np)))
return NO_IOMMU;
...
return ops->of_xlate(dev, iommu_spec);
but it's better to check it ourself :)
Fixes: 5fd577c3eac3 ("iommu/rockchip: Use OF_IOMMU to attach devices
automatically")
Signed-off-by: Arnd Bergmann
---
This warning appears to only have been introduced in linux-next after
the merge window opened.
---
drivers/iommu/rockchip-iommu.c | 6 +-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index 5fc8656c60f9..fe9c9cc1a9d4 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -1094,11 +1094,15 @@ static int rk_iommu_of_xlate(struct device *dev,
return -ENOMEM;
iommu_dev = of_find_device_by_node(args->np);
+ if (!iommu_dev) {
+ kfree(data);
+ return -ENODEV;
+ }
data->iommu = platform_get_drvdata(iommu_dev);
dev->archdata.iommu = data;
- of_dev_put(iommu_dev);
+ platform_device_put(iommu_dev);
return 0;
}
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[PATCH] iommu: amd: hide unused iommu_table_lock
The newly introduced lock is only used when CONFIG_IRQ_REMAP is enabled:
drivers/iommu/amd_iommu.c:86:24: error: 'iommu_table_lock' defined but not used
[-Werror=unused-variable]
static DEFINE_SPINLOCK(iommu_table_lock);
This moves the definition next to the user, within the #ifdef protected
section of the file.
Fixes: ea6166f4b83e ("iommu/amd: Split irq_lookup_table out of the
amd_iommu_devtable_lock")
Signed-off-by: Arnd Bergmann
---
drivers/iommu/amd_iommu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 2a99f0f14795..8fb8c737fffe 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -83,7 +83,6 @@
static DEFINE_SPINLOCK(amd_iommu_devtable_lock);
static DEFINE_SPINLOCK(pd_bitmap_lock);
-static DEFINE_SPINLOCK(iommu_table_lock);
/* List of all available dev_data structures */
static LLIST_HEAD(dev_data_list);
@@ -3562,6 +3561,7 @@ EXPORT_SYMBOL(amd_iommu_device_info);
*/
static struct irq_chip amd_ir_chip;
+static DEFINE_SPINLOCK(iommu_table_lock);
static void set_dte_irq_entry(u16 devid, struct irq_remap_table *table)
{
--
2.9.0
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[PATCH] iommu: rockchip: fix building without CONFIG_OF
We get a build error when compiling the iommu driver without CONFIG_OF:
drivers/iommu/rockchip-iommu.c: In function 'rk_iommu_of_xlate':
drivers/iommu/rockchip-iommu.c:1101:2: error: implicit declaration of function
'of_dev_put'; did you mean 'of_node_put'?
[-Werror=implicit-function-declaration]
This replaces the of_dev_put() with the equivalent platform_device_put(),
and adds an error check for of_find_device_by_node() returning NULL,
which seems to be appropriate here given that we pass the device into
platform_get_drvdata() next, and that of_find_device_by_node() might
theoretically return a NULL pointer.
Fixes: 5fd577c3eac3 ("iommu/rockchip: Use OF_IOMMU to attach devices
automatically")
Signed-off-by: Arnd Bergmann
---
This warning appears to only have been introduced in linux-next after
the merge window opened.
---
drivers/iommu/rockchip-iommu.c | 6 +-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index 5fc8656c60f9..fe9c9cc1a9d4 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -1094,11 +1094,15 @@ static int rk_iommu_of_xlate(struct device *dev,
return -ENOMEM;
iommu_dev = of_find_device_by_node(args->np);
+ if (!iommu_dev) {
+ kfree(data);
+ return -ENODEV;
+ }
data->iommu = platform_get_drvdata(iommu_dev);
dev->archdata.iommu = data;
- of_dev_put(iommu_dev);
+ platform_device_put(iommu_dev);
return 0;
}
--
2.9.0
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Re: [PATCH 27/37] iommu/arm-smmu-v3: Register fault workqueue
On 22/03/18 01:09, Yisheng Xie wrote:
> Hi Jean,
>
> On 2018/3/21 21:24, Jean-Philippe Brucker wrote:
>> Hi Yisheng,
>>
>> On 19/03/18 11:03, Yisheng Xie wrote:
>>> Hi Jean,
>>>
>>> [...]
@@ -3168,6 +3260,13 @@ static int arm_smmu_device_probe(struct
platform_device *pdev)
if (ret)
return ret;
+ if (smmu->features & (ARM_SMMU_FEAT_STALLS | ARM_SMMU_FEAT_PRI)) {
+ smmu->faultq_nb.notifier_call = arm_smmu_flush_queues;
+ ret = iommu_fault_queue_register(&smmu->faultq_nb);
+ if (ret)
+ return ret;
>>>
>>> I find a case here: CONFIG_IOMMU_FAULT=n, and smmu support feature STALLS
>>> or PRI,
>>> the device probe will failed here, is this what we want?
>>
>> Since CONFIG_ARM_SMMU_V3 selects CONFIG_IOMMU_FAULT, I don't think it
>> can happen.
>
> But CONFIG_IOMMU_FAULT can be changed after select, maybe can make it as
> unchangeable. Seems sensible, I don't see a reason to leave IOMMU_FAULT
> selectable
manually.
Thanks,
Jean
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