[6/6] of: Add KUnit test to confirm DTB is loaded
Commit Message
Add a KUnit test that confirms a DTB has been loaded, i.e. there is a
root node, and that the of_have_populated_dt() API works properly.
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: David Gow <davidgow@google.com>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
---
drivers/of/.kunitconfig | 3 ++
drivers/of/Kconfig | 9 ++++
drivers/of/Makefile | 2 +
drivers/of/of_test.c | 98 +++++++++++++++++++++++++++++++++++++++++
4 files changed, 112 insertions(+)
create mode 100644 drivers/of/.kunitconfig
create mode 100644 drivers/of/of_test.c
Comments
On Sat, 13 Jan 2024 at 04:07, Stephen Boyd <sboyd@kernel.org> wrote:
>
> Add a KUnit test that confirms a DTB has been loaded, i.e. there is a
> root node, and that the of_have_populated_dt() API works properly.
>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Frank Rowand <frowand.list@gmail.com>
> Cc: David Gow <davidgow@google.com>
> Cc: Brendan Higgins <brendan.higgins@linux.dev>
> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
> ---
I won't pretend to be a devicetree expert, but this looks good to me
from a KUnit point of view, and passes comfortably here.
checkpatch seems to have one complaint about the kconfig help text.
Personally, I think the brief description is fine.
Reviewed-by: David Gow <davidgow@google.com>
Cheers,
-- David
> drivers/of/.kunitconfig | 3 ++
> drivers/of/Kconfig | 9 ++++
> drivers/of/Makefile | 2 +
> drivers/of/of_test.c | 98 +++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 112 insertions(+)
> create mode 100644 drivers/of/.kunitconfig
> create mode 100644 drivers/of/of_test.c
>
> diff --git a/drivers/of/.kunitconfig b/drivers/of/.kunitconfig
> new file mode 100644
> index 000000000000..5a8fee11978c
> --- /dev/null
> +++ b/drivers/of/.kunitconfig
> @@ -0,0 +1,3 @@
> +CONFIG_KUNIT=y
> +CONFIG_OF=y
> +CONFIG_OF_KUNIT_TEST=y
> diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
> index 9628e48baa15..a527ba8451d9 100644
> --- a/drivers/of/Kconfig
> +++ b/drivers/of/Kconfig
> @@ -37,6 +37,15 @@ config OF_UNITTEST
>
> If unsure, say N here. This option is not safe to enable.
>
> +config OF_KUNIT_TEST
> + tristate "Devicetree KUnit DTB Test" if !KUNIT_ALL_TESTS
> + depends on KUNIT
> + default KUNIT_ALL_TESTS
> + help
> + This option builds KUnit unit tests for device tree infrastructure.
> +
> + If unsure, say N here, but this option is safe to enable.
> +
FYI:
WARNING: please write a help paragraph that fully describes the config symbol
#111: FILE: drivers/of/Kconfig:40:
> config OF_ALL_DTBS
> bool "Build all Device Tree Blobs"
> depends on COMPILE_TEST
> diff --git a/drivers/of/Makefile b/drivers/of/Makefile
> index df305348d1cb..251d33532148 100644
> --- a/drivers/of/Makefile
> +++ b/drivers/of/Makefile
> @@ -19,4 +19,6 @@ obj-y += kexec.o
> endif
> endif
>
> +obj-$(CONFIG_OF_KUNIT_TEST) += of_test.o
> +
> obj-$(CONFIG_OF_UNITTEST) += unittest-data/
> diff --git a/drivers/of/of_test.c b/drivers/of/of_test.c
> new file mode 100644
> index 000000000000..7609ad3081b9
> --- /dev/null
> +++ b/drivers/of/of_test.c
> @@ -0,0 +1,98 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * KUnit tests for OF APIs
> + */
> +#include <linux/module.h>
> +#include <linux/of.h>
> +
> +#include <kunit/test.h>
> +
> +/*
> + * Test that the root node "/" exists.
> + */
> +static void dtb_root_node_found_by_path(struct kunit *test)
> +{
> + struct device_node *np;
> +
> + np = of_find_node_by_path("/");
> + KUNIT_EXPECT_NOT_ERR_OR_NULL(test, np);
> + of_node_put(np);
> +}
> +
> +/*
> + * Test that the of_root global variable is always populated when DT
> + * code is enabled.
> + */
> +static void dtb_root_node_populates_of_root(struct kunit *test)
> +{
> + KUNIT_EXPECT_NOT_ERR_OR_NULL(test, of_root);
> +}
> +
> +static struct kunit_case dtb_test_cases[] = {
> + KUNIT_CASE(dtb_root_node_found_by_path),
> + KUNIT_CASE(dtb_root_node_populates_of_root),
> + {}
> +};
> +
> +/*
> + * Test suite to confirm a live DTB is loaded.
> + */
> +static struct kunit_suite dtb_suite = {
> + .name = "dtb",
> + .test_cases = dtb_test_cases,
> +};
> +
> +/*
> + * Test that calling of_have_populated_dt() returns false when
> + * the OF_EMPTY_ROOT flag isn't set.
> + */
> +static void of_have_populated_dt_false_when_flag_set(struct kunit *test)
> +{
> + bool was_set;
> +
> + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, of_root);
> +
> + was_set = of_node_test_and_set_flag(of_root, OF_EMPTY_ROOT);
> + KUNIT_EXPECT_FALSE(test, of_have_populated_dt());
> +
> + if (!was_set)
> + of_node_clear_flag(of_root, OF_EMPTY_ROOT);
> +}
> +
> +/*
> + * Test that calling of_have_populated_dt() returns false when
> + * the OF_EMPTY_ROOT flag isn't set.
> + */
> +static void of_have_populated_dt_true_when_flag_clear(struct kunit *test)
> +{
> + bool was_set;
> +
> + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, of_root);
> +
> + was_set = of_node_check_flag(of_root, OF_EMPTY_ROOT);
> + of_node_set_flag(of_root, OF_EMPTY_ROOT);
> + KUNIT_EXPECT_FALSE(test, of_have_populated_dt());
> +
> + if (was_set)
> + of_node_set_flag(of_root, OF_EMPTY_ROOT);
> +}
> +
> +static struct kunit_case of_have_populated_dt_test_cases[] = {
> + KUNIT_CASE(of_have_populated_dt_false_when_flag_set),
> + KUNIT_CASE(of_have_populated_dt_true_when_flag_clear),
> + {}
> +};
> +
> +/*
> + * Test suite to confirm behavior of of_have_populated_dt().
> + */
> +static struct kunit_suite of_have_populated_dt_suite = {
> + .name = "of_have_populated_dt",
> + .test_cases = of_have_populated_dt_test_cases,
> +};
> +
> +kunit_test_suites(
> + &dtb_suite,
> + &of_have_populated_dt_suite,
> +);
> +MODULE_LICENSE("GPL");
> --
> https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git/
> https://git.kernel.org/pub/scm/linux/kernel/git/sboyd/spmi.git
>
Quoting David Gow (2024-01-15 21:03:12)
> On Sat, 13 Jan 2024 at 04:07, Stephen Boyd <sboyd@kernel.org> wrote:
> >
> > Add a KUnit test that confirms a DTB has been loaded, i.e. there is a
> > root node, and that the of_have_populated_dt() API works properly.
> >
> > Cc: Rob Herring <robh+dt@kernel.org>
> > Cc: Frank Rowand <frowand.list@gmail.com>
> > Cc: David Gow <davidgow@google.com>
> > Cc: Brendan Higgins <brendan.higgins@linux.dev>
> > Signed-off-by: Stephen Boyd <sboyd@kernel.org>
> > ---
>
> I won't pretend to be a devicetree expert, but this looks good to me
> from a KUnit point of view, and passes comfortably here.
>
> checkpatch seems to have one complaint about the kconfig help text.
> Personally, I think the brief description is fine.
>
> Reviewed-by: David Gow <davidgow@google.com>
>
Thanks! I noticed that x86 has some devicetree init code. Did you happen
to try on an x86 kvm instance? Or only run on UML?
----8<----
diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c
index afd09924094e..650752d112a6 100644
--- a/arch/x86/kernel/devicetree.c
+++ b/arch/x86/kernel/devicetree.c
@@ -283,22 +283,24 @@ void __init x86_flattree_get_config(void)
u32 size, map_len;
void *dt;
- if (!initial_dtb)
- return;
+ if (initial_dtb) {
+ map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128);
- map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128);
+ dt = early_memremap(initial_dtb, map_len);
+ size = fdt_totalsize(dt);
+ if (map_len < size) {
+ early_memunmap(dt, map_len);
+ dt = early_memremap(initial_dtb, size);
+ map_len = size;
+ }
- dt = early_memremap(initial_dtb, map_len);
- size = fdt_totalsize(dt);
- if (map_len < size) {
- early_memunmap(dt, map_len);
- dt = early_memremap(initial_dtb, size);
- map_len = size;
+ early_init_dt_verify(dt);
}
- early_init_dt_verify(dt);
unflatten_and_copy_device_tree();
- early_memunmap(dt, map_len);
+
+ if (initial_dtb)
+ early_memunmap(dt, map_len);
}
#endif
On Tue, 23 Jan 2024 at 06:48, Stephen Boyd <sboyd@kernel.org> wrote:
>
> Quoting David Gow (2024-01-15 21:03:12)
> > On Sat, 13 Jan 2024 at 04:07, Stephen Boyd <sboyd@kernel.org> wrote:
> > >
> > > Add a KUnit test that confirms a DTB has been loaded, i.e. there is a
> > > root node, and that the of_have_populated_dt() API works properly.
> > >
> > > Cc: Rob Herring <robh+dt@kernel.org>
> > > Cc: Frank Rowand <frowand.list@gmail.com>
> > > Cc: David Gow <davidgow@google.com>
> > > Cc: Brendan Higgins <brendan.higgins@linux.dev>
> > > Signed-off-by: Stephen Boyd <sboyd@kernel.org>
> > > ---
> >
> > I won't pretend to be a devicetree expert, but this looks good to me
> > from a KUnit point of view, and passes comfortably here.
> >
> > checkpatch seems to have one complaint about the kconfig help text.
> > Personally, I think the brief description is fine.
> >
> > Reviewed-by: David Gow <davidgow@google.com>
> >
>
> Thanks! I noticed that x86 has some devicetree init code. Did you happen
> to try on an x86 kvm instance? Or only run on UML?
>
I admit, I only tested on UML, plus a quick check that the default
kunitconfig wasn't broken on anything else.
A further look is showing:
aarch64: PASSED
UML: PASSED
UML LLVM: PASSED
powerpc64: PASSED
m68k: FAILED
i386: FAILED
x86_64: FAILED
x86_64 KASAN: FAILED
The failures are all of the form:
> [15:18:34] ============ of_have_populated_dt (2 subtests) =============
> [15:18:34] # of_have_populated_dt_false_when_flag_set: ASSERTION FAILED at drivers/of/of_test.c:53
> [15:18:34] Expected of_root is not null, but is
> [15:18:34] [FAILED] of_have_populated_dt_false_when_flag_set
> [15:18:34] # of_have_populated_dt_true_when_flag_clear: ASSERTION FAILED at drivers/of/of_test.c:70
> [15:18:34] Expected of_root is not null, but is
> [15:18:34] [FAILED] of_have_populated_dt_true_when_flag_clear
> [15:18:34] # module: of_test
> [15:18:34] # of_have_populated_dt: pass:0 fail:2 skip:0 total:2
> [15:18:34] # Totals: pass:0 fail:2 skip:0 total:2
> [15:18:34] ============== [FAILED] of_have_populated_dt ===============
-- David
> ----8<----
> diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c
> index afd09924094e..650752d112a6 100644
> --- a/arch/x86/kernel/devicetree.c
> +++ b/arch/x86/kernel/devicetree.c
> @@ -283,22 +283,24 @@ void __init x86_flattree_get_config(void)
> u32 size, map_len;
> void *dt;
>
> - if (!initial_dtb)
> - return;
> + if (initial_dtb) {
> + map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128);
>
> - map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128);
> + dt = early_memremap(initial_dtb, map_len);
> + size = fdt_totalsize(dt);
> + if (map_len < size) {
> + early_memunmap(dt, map_len);
> + dt = early_memremap(initial_dtb, size);
> + map_len = size;
> + }
>
> - dt = early_memremap(initial_dtb, map_len);
> - size = fdt_totalsize(dt);
> - if (map_len < size) {
> - early_memunmap(dt, map_len);
> - dt = early_memremap(initial_dtb, size);
> - map_len = size;
> + early_init_dt_verify(dt);
> }
>
> - early_init_dt_verify(dt);
> unflatten_and_copy_device_tree();
> - early_memunmap(dt, map_len);
> +
> + if (initial_dtb)
> + early_memunmap(dt, map_len);
> }
> #endif
new file mode 100644
@@ -0,0 +1,3 @@
+CONFIG_KUNIT=y
+CONFIG_OF=y
+CONFIG_OF_KUNIT_TEST=y
@@ -37,6 +37,15 @@ config OF_UNITTEST
If unsure, say N here. This option is not safe to enable.
+config OF_KUNIT_TEST
+ tristate "Devicetree KUnit DTB Test" if !KUNIT_ALL_TESTS
+ depends on KUNIT
+ default KUNIT_ALL_TESTS
+ help
+ This option builds KUnit unit tests for device tree infrastructure.
+
+ If unsure, say N here, but this option is safe to enable.
+
config OF_ALL_DTBS
bool "Build all Device Tree Blobs"
depends on COMPILE_TEST
@@ -19,4 +19,6 @@ obj-y += kexec.o
endif
endif
+obj-$(CONFIG_OF_KUNIT_TEST) += of_test.o
+
obj-$(CONFIG_OF_UNITTEST) += unittest-data/
new file mode 100644
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit tests for OF APIs
+ */
+#include <linux/module.h>
+#include <linux/of.h>
+
+#include <kunit/test.h>
+
+/*
+ * Test that the root node "/" exists.
+ */
+static void dtb_root_node_found_by_path(struct kunit *test)
+{
+ struct device_node *np;
+
+ np = of_find_node_by_path("/");
+ KUNIT_EXPECT_NOT_ERR_OR_NULL(test, np);
+ of_node_put(np);
+}
+
+/*
+ * Test that the of_root global variable is always populated when DT
+ * code is enabled.
+ */
+static void dtb_root_node_populates_of_root(struct kunit *test)
+{
+ KUNIT_EXPECT_NOT_ERR_OR_NULL(test, of_root);
+}
+
+static struct kunit_case dtb_test_cases[] = {
+ KUNIT_CASE(dtb_root_node_found_by_path),
+ KUNIT_CASE(dtb_root_node_populates_of_root),
+ {}
+};
+
+/*
+ * Test suite to confirm a live DTB is loaded.
+ */
+static struct kunit_suite dtb_suite = {
+ .name = "dtb",
+ .test_cases = dtb_test_cases,
+};
+
+/*
+ * Test that calling of_have_populated_dt() returns false when
+ * the OF_EMPTY_ROOT flag isn't set.
+ */
+static void of_have_populated_dt_false_when_flag_set(struct kunit *test)
+{
+ bool was_set;
+
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, of_root);
+
+ was_set = of_node_test_and_set_flag(of_root, OF_EMPTY_ROOT);
+ KUNIT_EXPECT_FALSE(test, of_have_populated_dt());
+
+ if (!was_set)
+ of_node_clear_flag(of_root, OF_EMPTY_ROOT);
+}
+
+/*
+ * Test that calling of_have_populated_dt() returns false when
+ * the OF_EMPTY_ROOT flag isn't set.
+ */
+static void of_have_populated_dt_true_when_flag_clear(struct kunit *test)
+{
+ bool was_set;
+
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, of_root);
+
+ was_set = of_node_check_flag(of_root, OF_EMPTY_ROOT);
+ of_node_set_flag(of_root, OF_EMPTY_ROOT);
+ KUNIT_EXPECT_FALSE(test, of_have_populated_dt());
+
+ if (was_set)
+ of_node_set_flag(of_root, OF_EMPTY_ROOT);
+}
+
+static struct kunit_case of_have_populated_dt_test_cases[] = {
+ KUNIT_CASE(of_have_populated_dt_false_when_flag_set),
+ KUNIT_CASE(of_have_populated_dt_true_when_flag_clear),
+ {}
+};
+
+/*
+ * Test suite to confirm behavior of of_have_populated_dt().
+ */
+static struct kunit_suite of_have_populated_dt_suite = {
+ .name = "of_have_populated_dt",
+ .test_cases = of_have_populated_dt_test_cases,
+};
+
+kunit_test_suites(
+ &dtb_suite,
+ &of_have_populated_dt_suite,
+);
+MODULE_LICENSE("GPL");