| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <aO9vI1aEhnyZx1PL@google.com>
Date: Wed, 15 Oct 2025 09:53:39 +0000
From: Mostafa Saleh <smostafa@...gle.com>
To: Robin Murphy <robin.murphy@....com>
Cc: iommu@...ts.linux.dev, linux-arm-kernel@...ts.infradead.org,
linux-kernel@...r.kernel.org, will@...nel.org, joro@...tes.org,
jgg@...pe.ca, praan@...gle.com, Jason Gunthorpe <jgg@...dia.com>
Subject: Re: [PATCH v5 4/4] iommu/io-pgtable-arm-selftests: Use KUnit
On Tue, Oct 14, 2025 at 02:43:53PM +0100, Robin Murphy wrote:
> On 2025-09-29 4:49 pm, Mostafa Saleh wrote:
> > Integrate the selftests as part of kunit.
> >
> > Now instead of the test only being run at boot, it can run:
> >
> > - With CONFIG_IOMMU_IO_PGTABLE_LPAE_KUNIT_TEST=y
> > It will automatically run at boot as before.
> >
> > - Otherwise with CONFIG_IOMMU_IO_PGTABLE_KUNIT_TEST=m:
> > 1) on module load:
> > Once the module load the self test will run
> > # modprobe io-pgtable-arm-selftests
> >
> > 2) debugfs
> > With CONFIG_KUNIT_DEBUGFS=y You can run the test with
> > # echo 1 > /sys/kernel/debug/kunit/io-pgtable-arm-test/run
> >
> > 3) Using kunit.py
> > You can also use the helper script which uses Qemu in the background
> >
> > # ./tools/testing/kunit/kunit.py run --build_dir build_kunit_arm64 --arch arm64 \
> > --make_options LLVM=1 --kunitconfig ./kunit/kunitconfig
> > [18:01:09] ============= io-pgtable-arm-test (1 subtest) ==============
> > [18:01:09] [PASSED] arm_lpae_do_selftests
> > [18:01:09] =============== [PASSED] io-pgtable-arm-test ===============
> > [18:01:09] ============================================================
> >
> > Suggested-by: Jason Gunthorpe <jgg@...pe.ca>
> > Reviewed-by: Jason Gunthorpe <jgg@...dia.com>
> > Reviewed-by: Pranjal Shrivastava <praan@...gle.com>
> > Signed-off-by: Mostafa Saleh <smostafa@...gle.com>
> > ---
> > drivers/iommu/Kconfig | 11 ++--
> > drivers/iommu/Makefile | 2 +-
> > drivers/iommu/io-pgtable-arm-selftests.c | 82 +++++++++++++-----------
> > 3 files changed, 51 insertions(+), 44 deletions(-)
> >
> > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> > index 553522ef3ca9..d50685433347 100644
> > --- a/drivers/iommu/Kconfig
> > +++ b/drivers/iommu/Kconfig
> > @@ -40,12 +40,13 @@ config IOMMU_IO_PGTABLE_LPAE
> > sizes at both stage-1 and stage-2, as well as address spaces
> > up to 48-bits in size.
> > -config IOMMU_IO_PGTABLE_LPAE_SELFTEST
> > - tristate "LPAE selftests"
> > - depends on IOMMU_IO_PGTABLE_LPAE
> > +config IOMMU_IO_PGTABLE_LPAE_KUNIT_TEST
> > + tristate "KUnit tests for LPAE"
> > + depends on IOMMU_IO_PGTABLE_LPAE && KUNIT
> > + default KUNIT_ALL_TESTS
> > help
> > - Enable self-tests for LPAE page table allocator. This performs
> > - a series of page-table consistency checks during boot.
> > + Enable kunit tests for LPAE page table allocator. This performs
> > + a series of page-table consistency checks.
> > If unsure, say N here.
> > diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
> > index 5250a2eea13f..ac3851570303 100644
> > --- a/drivers/iommu/Makefile
> > +++ b/drivers/iommu/Makefile
> > @@ -12,7 +12,7 @@ obj-$(CONFIG_IOMMU_DMA) += dma-iommu.o
> > obj-$(CONFIG_IOMMU_IO_PGTABLE) += io-pgtable.o
> > obj-$(CONFIG_IOMMU_IO_PGTABLE_ARMV7S) += io-pgtable-arm-v7s.o
> > obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE) += io-pgtable-arm.o
> > -obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE_SELFTEST) += io-pgtable-arm-selftests.o
> > +obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE_KUNIT_TEST) += io-pgtable-arm-selftests.o
> > obj-$(CONFIG_IOMMU_IO_PGTABLE_DART) += io-pgtable-dart.o
> > obj-$(CONFIG_IOMMU_IOVA) += iova.o
> > obj-$(CONFIG_OF_IOMMU) += of_iommu.o
> > diff --git a/drivers/iommu/io-pgtable-arm-selftests.c b/drivers/iommu/io-pgtable-arm-selftests.c
> > index 32c6a5c7af53..b61849a8a685 100644
> > --- a/drivers/iommu/io-pgtable-arm-selftests.c
> > +++ b/drivers/iommu/io-pgtable-arm-selftests.c
> > @@ -6,7 +6,8 @@
> > *
> > * Author: Will Deacon <will.deacon@....com>
> > */
> > -#include <linux/device/faux.h>
> > +#include <kunit/device.h>
> > +#include <kunit/test.h>
> > #include <linux/io-pgtable.h>
> > #include <linux/kernel.h>
> > @@ -47,13 +48,14 @@ static void arm_lpae_dump_ops(struct io_pgtable_ops *ops)
> > cfg->pgsize_bitmap, cfg->ias, cfg->oas);
> > }
> > -#define __FAIL(ops, i) ({ \
> > - WARN(1, "selftest: test failed for fmt idx %d\n", (i)); \
> > - arm_lpae_dump_ops(ops); \
> > - -EFAULT; \
> > +#define __FAIL(test, ops, i) ({ \
> > + KUNIT_FAIL(test, ""); \
> > + kunit_err(test, "selftest: test failed for fmt idx %d\n", (i)); \
>
> This looks suspect - AFAICS open-coded kunit_err() is intended for test
> infrastucture errors (like the allocation in the next hunk below), while for
> an actual test report message it seems it should just be:
>
> KUNIT_FAIL(test, "selftest: test failed for fmt idx %d\n", (i));
I see, I used kunit_err, as KUNIT_FAIL adds extra information which was
noisy to be printed more than once as:
# arm_lpae_do_selftests: EXPECTATION FAILED at drivers/iommu/io-pgtable-arm-selftests.c:91
I will check if there is a better way to do this.
>
> > + arm_lpae_dump_ops(ops); \
> > + -EFAULT; \
> > })
> > -static int arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
> > +static int arm_lpae_run_tests(struct kunit *test, struct io_pgtable_cfg *cfg)
> > {
> > static const enum io_pgtable_fmt fmts[] = {
> > ARM_64_LPAE_S1,
> > @@ -69,7 +71,7 @@ static int arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
> > cfg_cookie = cfg;
> > ops = alloc_io_pgtable_ops(fmts[i], cfg, cfg);
> > if (!ops) {
> > - pr_err("selftest: failed to allocate io pgtable ops\n");
> > + kunit_err(test, "selftest: failed to allocate io pgtable ops\n");
> > return -ENOMEM;
> > }
> > @@ -78,13 +80,13 @@ static int arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
> > * Empty page tables shouldn't provide any translations.
> > */
> > if (ops->iova_to_phys(ops, 42))
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > if (ops->iova_to_phys(ops, SZ_1G + 42))
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > if (ops->iova_to_phys(ops, SZ_2G + 42))
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > /*
> > * Distinct mappings of different granule sizes.
> > @@ -97,16 +99,16 @@ static int arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
> > IOMMU_READ | IOMMU_WRITE |
> > IOMMU_NOEXEC | IOMMU_CACHE,
> > GFP_KERNEL, &mapped))
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > /* Overlapping mappings */
> > if (!ops->map_pages(ops, iova, iova + size, size, 1,
> > IOMMU_READ | IOMMU_NOEXEC,
> > GFP_KERNEL, &mapped))
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > iova += SZ_1G;
> > }
> > @@ -117,18 +119,18 @@ static int arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
> > size = 1UL << j;
> > if (ops->unmap_pages(ops, iova, size, 1, NULL) != size)
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > if (ops->iova_to_phys(ops, iova + 42))
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > /* Remap full block */
> > if (ops->map_pages(ops, iova, iova, size, 1,
> > IOMMU_WRITE, GFP_KERNEL, &mapped))
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > iova += SZ_1G;
> > }
> > @@ -144,11 +146,11 @@ static int arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
> > IOMMU_READ | IOMMU_WRITE |
> > IOMMU_NOEXEC | IOMMU_CACHE,
> > GFP_KERNEL, &mapped))
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > if (mapped != size)
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > if (ops->unmap_pages(ops, iova, size, 1, NULL) != size)
> > - return __FAIL(ops, i);
> > + return __FAIL(test, ops, i);
> > free_io_pgtable_ops(ops);
> > }
> > @@ -156,7 +158,7 @@ static int arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
> > return 0;
> > }
> > -static int arm_lpae_do_selftests(void)
> > +static void arm_lpae_do_selftests(struct kunit *test)
> > {
> > static const unsigned long pgsize[] = {
> > SZ_4K | SZ_2M | SZ_1G,
> > @@ -169,18 +171,19 @@ static int arm_lpae_do_selftests(void)
> > };
> > int i, j, k, pass = 0, fail = 0;
> > - struct faux_device *dev;
> > + struct device *dev;
> > struct io_pgtable_cfg cfg = {
> > .tlb = &dummy_tlb_ops,
> > .coherent_walk = true,
> > .quirks = IO_PGTABLE_QUIRK_NO_WARN,
> > };
> > - dev = faux_device_create("io-pgtable-test", NULL, 0);
> > - if (!dev)
> > - return -ENOMEM;
> > + dev = kunit_device_register(test, "io-pgtable-test");
> > + KUNIT_EXPECT_NOT_ERR_OR_NULL(test, dev);
>
> Conversely, this is infrastructure, not an actual test of expected
> io-pgtable behaviour, so I think just:
>
> cfg.iommu_dev = kunit_device_register(test, "io-pgtable-test");
> if (IS_ERR(cfg.iommu_dev))
> return;
>
> (it doesn't return NULLs either)
>
Yes, I was not sure about this one, when checking the code base, every test
handles kunit_device_register() failure differently, this seemed the
most strict one so I used it, I will update that in the next version.
> Otherwise, there's clearly scope for plenty more follow-up work streamlining
> and breaking the whole thing up into KUnit idioms, pulling the v7s test in,
> etc... However as a first step to at least set things firmly on the right
> KUnit-shaped path, I agree this seems enough for now.
>
I agree, ultimately every configuration should be a test, which can be
even broken down to smaller cases. I will look in to that next.
Thanks,
Mostafa
> Thanks,
> Robin.
>
> > + if (IS_ERR_OR_NULL(dev))
> > + return;
> > - cfg.iommu_dev = &dev->dev;
> > + cfg.iommu_dev = dev;
> > for (i = 0; i < ARRAY_SIZE(pgsize); ++i) {
> > for (j = 0; j < ARRAY_SIZE(address_size); ++j) {
> > @@ -189,9 +192,9 @@ static int arm_lpae_do_selftests(void)
> > cfg.pgsize_bitmap = pgsize[i];
> > cfg.ias = address_size[k];
> > cfg.oas = address_size[j];
> > - pr_info("selftest: pgsize_bitmap 0x%08lx, IAS %u OAS %u\n",
> > - pgsize[i], cfg.ias, cfg.oas);
> > - if (arm_lpae_run_tests(&cfg))
> > + kunit_info(test, "selftest: pgsize_bitmap 0x%08lx, IAS %u OAS %u\n",
> > + pgsize[i], cfg.ias, cfg.oas);
> > + if (arm_lpae_run_tests(test, &cfg))
> > fail++;
> > else
> > pass++;
> > @@ -199,17 +202,20 @@ static int arm_lpae_do_selftests(void)
> > }
> > }
> > - pr_info("selftest: completed with %d PASS %d FAIL\n", pass, fail);
> > - faux_device_destroy(dev);
> > -
> > - return fail ? -EFAULT : 0;
> > + kunit_info(test, "selftest: completed with %d PASS %d FAIL\n", pass, fail);
> > }
> > -static void arm_lpae_exit_selftests(void)
> > -{
> > -}
> > +static struct kunit_case io_pgtable_arm_test_cases[] = {
> > + KUNIT_CASE(arm_lpae_do_selftests),
> > + {},
> > +};
> > +
> > +static struct kunit_suite io_pgtable_arm_test = {
> > + .name = "io-pgtable-arm-test",
> > + .test_cases = io_pgtable_arm_test_cases,
> > +};
> > +
> > +kunit_test_suite(io_pgtable_arm_test);
> > -subsys_initcall(arm_lpae_do_selftests);
> > -module_exit(arm_lpae_exit_selftests);
> > MODULE_DESCRIPTION("io-pgtable-arm library selftest");
> > MODULE_LICENSE("GPL");
Powered by blists - more mailing lists