Commit Graph

6 Commits

Author SHA1 Message Date
Willem de Bruijn
e6daf129cc net: gso_test: support CONFIG_MAX_SKB_FRAGS up to 45
The test allocs a single page to hold all the frag_list skbs. This
is insufficient on kernels with CONFIG_MAX_SKB_FRAGS=45, due to the
increased skb_shared_info frags[] array length.

        gso_test_func: ASSERTION FAILED at net/core/gso_test.c:210
        Expected alloc_size <= ((1UL) << 12), but
            alloc_size == 5075 (0x13d3)
            ((1UL) << 12) == 4096 (0x1000)

Simplify the logic. Just allocate a page for each frag_list skb.

Fixes: 4688ecb138 ("net: expand skb_segment unit test with frag_list coverage")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-11-13 11:04:38 +00:00
Florian Westphal
1b2d3b45c1 net: gso_test: release each segment individually
consume_skb() doesn't walk the segment list, so segments other than
the first are leaked.

Move this skb_consume call into the loop.

Cc: Willem de Bruijn <willemb@google.com>
Fixes: b3098d32ed ("net: add skb_segment kunit test")
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-10-17 11:32:05 +01:00
Florian Westphal
2f0968a030 net: gso_test: fix build with gcc-12 and earlier
gcc 12 errors out with:
net/core/gso_test.c:58:48: error: initializer element is not constant
   58 |                 .segs = (const unsigned int[]) { gso_size },

This version isn't old (2022), so switch to preprocessor-bsaed constant
instead of 'static const int'.

Cc: Willem de Bruijn <willemb@google.com>
Reported-by: Tasmiya Nalatwad <tasmiya@linux.vnet.ibm.com>
Closes: https://lore.kernel.org/netdev/79fbe35c-4dd1-4f27-acb2-7a60794bc348@linux.vnet.ibm.com/
Fixes: 1b4fa28a8b ("net: parametrize skb_segment unit test to expand coverage")
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20231012120901.10765-1-fw@strlen.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-10-12 15:34:08 +02:00
Willem de Bruijn
4688ecb138 net: expand skb_segment unit test with frag_list coverage
Expand the test with these variants that use skb frag_list:

- GSO_TEST_FRAG_LIST:             frag_skb length is gso_size
- GSO_TEST_FRAG_LIST_PURE:        same, data exclusively in frag skbs
- GSO_TEST_FRAG_LIST_NON_UNIFORM: frag_skb length may vary
- GSO_TEST_GSO_BY_FRAGS:          frag_skb length defines gso_size,
                                  i.e., segs may have varying sizes.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-10-11 10:39:01 +01:00
Willem de Bruijn
1b4fa28a8b net: parametrize skb_segment unit test to expand coverage
Expand the test with variants

- GSO_TEST_NO_GSO:      payload size less than or equal to gso_size
- GSO_TEST_FRAGS:       payload in both linear and page frags
- GSO_TEST_FRAGS_PURE:  payload exclusively in page frags
- GSO_TEST_GSO_PARTIAL: produce one gso segment of multiple of gso_size,
                        plus optionally one non-gso trailer segment

Define a test struct that encodes the input gso skb and output segs.
Input in terms of linear and fragment lengths. Output as length of
each segment.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-10-11 10:39:01 +01:00
Willem de Bruijn
b3098d32ed net: add skb_segment kunit test
Add unit testing for skb segment. This function is exercised by many
different code paths, such as GSO_PARTIAL or GSO_BY_FRAGS, linear
(with or without head_frag), frags or frag_list skbs, etc.

It is infeasible to manually run tests that cover all code paths when
making changes. The long and complex function also makes it hard to
establish through analysis alone that a patch has no unintended
side-effects.

Add code coverage through kunit regression testing. Introduce kunit
infrastructure for tests under net/core, and add this first test.

This first skb_segment test exercises a simple case: a linear skb.
Follow-on patches will parametrize the test and add more variants.

Tested: Built and ran the test with

    make ARCH=um mrproper

    ./tools/testing/kunit/kunit.py run \
        --kconfig_add CONFIG_NET=y \
        --kconfig_add CONFIG_DEBUG_KERNEL=y \
        --kconfig_add CONFIG_DEBUG_INFO=y \
        --kconfig_add=CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y \
        net_core_gso

Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-10-11 10:39:01 +01:00