| Message ID | 20241216201148.535115-1-briannorris@chromium.org |
|---|---|
| Headers | show |
| Series | drivers: base: Don't match device with NULL of_node/fwnode/etc + tests | expand |
On Tue, 17 Dec 2024 at 04:12, Brian Norris <briannorris@chromium.org> wrote: > > of_find_device_by_node(), bus_find_device_by_of_node(), > bus_find_device_by_fwnode(), ..., all produce arbitrary results when > provided with a NULL of_node, fwnode, ACPI handle, etc. This is > counterintuitive, and the source of a few bugs, such as the one fixed by > commit 5c8418cf4025 ("PCI/pwrctrl: Unregister platform device only if > one actually exists"). > > It's hard to imagine a good reason that these device_match_*() APIs > should return 'true' for a NULL argument. Augment these to return 0 > (false). > > Reviewed-by: Rob Herring (Arm) <robh@kernel.org> > Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > Signed-off-by: Brian Norris <briannorris@chromium.org> > --- Seems sensible enough to me. Acked-by: David Gow <davidgow@google.com> I assume this series (including the KUnit test changes) will go in via Greg. Cheers, -- David > > Changes in v3: > * Add Rafael's Acked-by > > Changes in v2: > * Add Rob's Reviewed-by > > drivers/base/core.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/base/core.c b/drivers/base/core.c > index 94865c9d8adc..2b7b13fc36d7 100644 > --- a/drivers/base/core.c > +++ b/drivers/base/core.c > @@ -5246,13 +5246,13 @@ EXPORT_SYMBOL_GPL(device_match_name); > > int device_match_of_node(struct device *dev, const void *np) > { > - return dev->of_node == np; > + return np && dev->of_node == np; > } > EXPORT_SYMBOL_GPL(device_match_of_node); > > int device_match_fwnode(struct device *dev, const void *fwnode) > { > - return dev_fwnode(dev) == fwnode; > + return fwnode && dev_fwnode(dev) == fwnode; > } > EXPORT_SYMBOL_GPL(device_match_fwnode); > > @@ -5264,13 +5264,13 @@ EXPORT_SYMBOL_GPL(device_match_devt); > > int device_match_acpi_dev(struct device *dev, const void *adev) > { > - return ACPI_COMPANION(dev) == adev; > + return adev && ACPI_COMPANION(dev) == adev; > } > EXPORT_SYMBOL(device_match_acpi_dev); > > int device_match_acpi_handle(struct device *dev, const void *handle) > { > - return ACPI_HANDLE(dev) == handle; > + return handle && ACPI_HANDLE(dev) == handle; > } > EXPORT_SYMBOL(device_match_acpi_handle); > > -- > 2.47.1.613.gc27f4b7a9f-goog >
On Tue, 17 Dec 2024 at 04:12, Brian Norris <briannorris@chromium.org> wrote: > > We recently updated these device_match*() (and therefore, various > *find_device_by*()) functions to return a consistent 'false' value when > trying to match a NULL handle. Add tests for this. > > This provides regression-testing coverage for the sorts of bugs that > underly commit 5c8418cf4025 ("PCI/pwrctrl: Unregister platform device > only if one actually exists"). > > Reviewed-by: Maxime Ripard <mripard@kernel.org> > Signed-off-by: Brian Norris <briannorris@chromium.org> > --- > Thanks. This looks good to me. Reviewed-by: David Gow <davidgow@google.com> -- David > Changes in v3: > * Fix potential leak in test error case > * Add Maxime's Reviewed-by > > Changes in v2: > * Keep "devm" and "match" tests in separate suites > > drivers/base/test/platform-device-test.c | 41 +++++++++++++++++++++++- > 1 file changed, 40 insertions(+), 1 deletion(-) > > diff --git a/drivers/base/test/platform-device-test.c b/drivers/base/test/platform-device-test.c > index ea05b8785743..6355a2231b74 100644 > --- a/drivers/base/test/platform-device-test.c > +++ b/drivers/base/test/platform-device-test.c > @@ -1,8 +1,11 @@ > // SPDX-License-Identifier: GPL-2.0 > > +#include <kunit/platform_device.h> > #include <kunit/resource.h> > > #include <linux/device.h> > +#include <linux/device/bus.h> > +#include <linux/of_platform.h> > #include <linux/platform_device.h> > > #define DEVICE_NAME "test" > @@ -217,7 +220,43 @@ static struct kunit_suite platform_device_devm_test_suite = { > .test_cases = platform_device_devm_tests, > }; > > -kunit_test_suite(platform_device_devm_test_suite); > +static void platform_device_find_by_null_test(struct kunit *test) > +{ > + struct platform_device *pdev; > + int ret; > + > + pdev = kunit_platform_device_alloc(test, DEVICE_NAME, PLATFORM_DEVID_NONE); > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev); > + > + ret = kunit_platform_device_add(test, pdev); > + KUNIT_ASSERT_EQ(test, ret, 0); > + > + KUNIT_EXPECT_PTR_EQ(test, of_find_device_by_node(NULL), NULL); > + > + KUNIT_EXPECT_PTR_EQ(test, bus_find_device_by_of_node(&platform_bus_type, NULL), NULL); > + KUNIT_EXPECT_PTR_EQ(test, bus_find_device_by_fwnode(&platform_bus_type, NULL), NULL); > + KUNIT_EXPECT_PTR_EQ(test, bus_find_device_by_acpi_dev(&platform_bus_type, NULL), NULL); > + > + KUNIT_EXPECT_FALSE(test, device_match_of_node(&pdev->dev, NULL)); > + KUNIT_EXPECT_FALSE(test, device_match_fwnode(&pdev->dev, NULL)); > + KUNIT_EXPECT_FALSE(test, device_match_acpi_dev(&pdev->dev, NULL)); > + KUNIT_EXPECT_FALSE(test, device_match_acpi_handle(&pdev->dev, NULL)); > +} > + > +static struct kunit_case platform_device_match_tests[] = { > + KUNIT_CASE(platform_device_find_by_null_test), > + {} > +}; > + > +static struct kunit_suite platform_device_match_test_suite = { > + .name = "platform-device-match", > + .test_cases = platform_device_match_tests, > +}; > + > +kunit_test_suites( > + &platform_device_devm_test_suite, > + &platform_device_match_test_suite, > +); > > MODULE_DESCRIPTION("Test module for platform devices"); > MODULE_AUTHOR("Maxime Ripard <mripard@kernel.org>"); > -- > 2.47.1.613.gc27f4b7a9f-goog >
On 12/18/24 22:45, David Gow wrote: > On Tue, 17 Dec 2024 at 04:12, Brian Norris <briannorris@chromium.org> wrote: >> >> We recently updated these device_match*() (and therefore, various >> *find_device_by*()) functions to return a consistent 'false' value when >> trying to match a NULL handle. Add tests for this. >> >> This provides regression-testing coverage for the sorts of bugs that >> underly commit 5c8418cf4025 ("PCI/pwrctrl: Unregister platform device >> only if one actually exists"). >> >> Reviewed-by: Maxime Ripard <mripard@kernel.org> >> Signed-off-by: Brian Norris <briannorris@chromium.org> >> --- >> > > Thanks. This looks good to me. > > Reviewed-by: David Gow <davidgow@google.com> > > > This one also can go through Greg's drivers tree: Acked-by: Shuah Khan <skhan@linuxfoundation.org> thanks, -- Shuah
This series: 1. makes the behavior of_find_device_by_node(), bus_find_device_by_of_node(), bus_find_device_by_fwnode(), etc., more consistent when provided with a NULL node/handle; 2. adds kunit tests to validate the new NULL-argument behavior; and 3. makes some related improvements and refactoring for the drivers/base/ kunit tests. This series aims to prevent problems like the ones resolved in commit 5c8418cf4025 ("PCI/pwrctrl: Unregister platform device only if one actually exists"). Changes in v3: * Fix potential leak in test error case Changes in v2: * CC LKML (oops!) * Keep "devm" and "match" tests in separate suites Brian Norris (3): drivers: base: Don't match devices with NULL of_node/fwnode/etc drivers: base: test: Enable device model tests with KUNIT_ALL_TESTS drivers: base: test: Add ...find_device_by...(... NULL) tests drivers/base/core.c | 8 ++--- drivers/base/test/Kconfig | 1 + drivers/base/test/platform-device-test.c | 41 +++++++++++++++++++++++- 3 files changed, 45 insertions(+), 5 deletions(-)