RE: [PATCH v2 3/4] nitro_enclaves: add test framework for the misc functionality

["Longpeng (Mike, Cloud Infrastructure Service Product Dept.)" <longpeng2@huawei.com>]

> -----Original Message-----
> From: Paraschiv, Andra-Irina [mailto:andraprs@amazon.com]
> Sent: Sunday, October 3, 2021 9:50 PM
> To: Longpeng (Mike, Cloud Infrastructure Service Product Dept.)
> <longpeng2@huawei.com>
> Cc: linux-kernel@vger.kernel.org; Gonglei (Arei) <arei.gonglei@huawei.com>;
> gregkh@linuxfoundation.org; kamal@canonical.com; pbonzini@redhat.com;
> sgarzare@redhat.com; stefanha@redhat.com; vkuznets@redhat.com;
> ne-devel-upstream@amazon.com; lexnv@amazon.com; alcioa@amazon.com
> Subject: Re: [PATCH v2 3/4] nitro_enclaves: add test framework for the misc
> functionality
> 
> 
> 
> On 21/09/2021 18:10, Longpeng(Mike) wrote:
> > Add test framework for the misc functionality.
> 
> Let's add more specifics here.
> 
> nitro_enclaves: Add KUnit tests setup for the misc device functionality
> 
> Add the initial setup for the KUnit tests that will target the Nitro
> Enclaves misc device functionality.
> 

OK, thanks.

> >
> > Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
> > ---
> >   drivers/virt/nitro_enclaves/Kconfig        |  8 ++++++++
> >   drivers/virt/nitro_enclaves/ne_misc_dev.c  | 27
> +++++++++++++++++++++++++++
> >   drivers/virt/nitro_enclaves/ne_misc_test.c | 17 +++++++++++++++++
> >   3 files changed, 52 insertions(+)
> >   create mode 100644 drivers/virt/nitro_enclaves/ne_misc_test.c
> 
> Please modify in all places where necessary to mention Nitro Enclaves
> "misc device", instead of just "misc", to be more specific.
> 
> For example, here can be "ne_misc_dev_test.c".
> 

OK.

> >
> > diff --git a/drivers/virt/nitro_enclaves/Kconfig
> b/drivers/virt/nitro_enclaves/Kconfig
> > index 8c9387a..24c54da 100644
> > --- a/drivers/virt/nitro_enclaves/Kconfig
> > +++ b/drivers/virt/nitro_enclaves/Kconfig
> > @@ -18,3 +18,11 @@ config NITRO_ENCLAVES
> >
> >   	  To compile this driver as a module, choose M here.
> >   	  The module will be called nitro_enclaves.
> > +
> > +config NITRO_ENCLAVES_MISC_TEST
> 
> NITRO_ENCLAVES_MISC_DEV_TEST
> 
> > +	bool "Tests for the misc functionality of Nitro enclaves"
> 
> misc device functionality of the Nitro Enclaves
> 
> > +	depends on NITRO_ENCLAVES && KUNIT=y
> > +	help
> > +	  Enable KUnit tests for the misc functionality of Nitro Enclaves. Select
> 
> misc device functionality of the Nitro Enclaves
> 

OK, thanks.

> > +	  this option only if you will boot the kernel for the purpose of running
> > +	  unit tests (e.g. under UML or qemu). If unsure, say N.
> > diff --git a/drivers/virt/nitro_enclaves/ne_misc_dev.c
> b/drivers/virt/nitro_enclaves/ne_misc_dev.c
> > index d551b88..0131e1b 100644
> > --- a/drivers/virt/nitro_enclaves/ne_misc_dev.c
> > +++ b/drivers/virt/nitro_enclaves/ne_misc_dev.c
> > @@ -1735,8 +1735,33 @@ static long ne_ioctl(struct file *file, unsigned int
> cmd, unsigned long arg)
> >   	return 0;
> >   }
> >
> > +#if defined(CONFIG_NITRO_ENCLAVES_MISC_TEST)
> > +#include "ne_misc_test.c"
> > +
> > +static inline int ne_misc_test_init(void)
> > +{
> > +	return __kunit_test_suites_init(ne_misc_test_suites);
> > +}
> > +
> > +static inline void ne_misc_test_exit(void)
> > +{
> > +	__kunit_test_suites_exit(ne_misc_test_suites);
> > +}
> > +#else
> > +static inline int ne_misc_test_init(void)
> > +{
> > +	return 0;
> > +}
> > +
> > +static inline void ne_misc_test_exit(void)
> > +{
> > +}
> > +#endif
> 
> s/misc/misc_dev/g
> 
> Why are these needed? Can't the test suite be setup using
> "kunit_test_suite" as in the KUnit documentation example [1]?
> 
> Wouldn't be necessary to conditionally compile the ne_misc_dev_test,
> based on the kernel config above?
> 
> [1]
> https://www.kernel.org/doc/html/latest/dev-tools/kunit/start.html#writing-y
> our-first-test
> 

Both of these two ways are supported in kernel, for example [2].

There are two reasons why I choose this way:
1. The functions (to test) in "ne_misc_dev.c" are 'static', we cannot invoke
    them in  "ne_misc_dev_test.c".
2. kunit_test_suite defines a module init function internal, and "ne_misc_dev.c"
    also defines one, so they cannot be compiled into one module.


[2]
https://elixir.bootlin.com/linux/v5.15-rc4/source/drivers/mmc/host/sdhci-of-aspeed.c#L612

> > +
> >   static int __init ne_init(void)
> >   {
> > +	ne_misc_test_init();
> > +
> >   	mutex_init(&ne_cpu_pool.mutex);
> >
> >   	return pci_register_driver(&ne_pci_driver);
> > @@ -1747,6 +1772,8 @@ static void __exit ne_exit(void)
> >   	pci_unregister_driver(&ne_pci_driver);
> >
> >   	ne_teardown_cpu_pool();
> > +
> > +	ne_misc_test_exit();
> >   }
> >
> >   module_init(ne_init);
> > diff --git a/drivers/virt/nitro_enclaves/ne_misc_test.c
> b/drivers/virt/nitro_enclaves/ne_misc_test.c
> > new file mode 100644
> > index 0000000..3426c35
> > --- /dev/null
> > +++ b/drivers/virt/nitro_enclaves/ne_misc_test.c
> > @@ -0,0 +1,17 @@
> > +// SPDX-License-Identifier: GPL-2.0-or-later
> > +
> > +#include <kunit/test.h>
> > +
> > +static struct kunit_case ne_misc_test_cases[] = {
> > +	{}
> > +};
> > +
> > +static struct kunit_suite ne_misc_test_suite = {
> > +	.name = "ne_misc_test",
> > +	.test_cases = ne_misc_test_cases,
> > +};
> > +
> > +static struct kunit_suite *ne_misc_test_suites[] = {
> > +	&ne_misc_test_suite,
> > +	NULL
> > +};
> >
> 
> Can replace "ne_misc" with "ne_misc_dev".
> 
> Thanks,
> Andra
> 
> 
> 
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