Messages in this thread | | | Subject | Re: [PATCH 2/2] selftests/bpf: add verifier test for PTR_TO_MEM spill | From | Daniel Borkmann <> | Date | Tue, 12 Jan 2021 16:43:19 +0100 |
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On 1/12/21 4:35 PM, Gilad Reti wrote: > On Tue, Jan 12, 2021 at 4:56 PM KP Singh <kpsingh@kernel.org> wrote: >> On Tue, Jan 12, 2021 at 10:16 AM Gilad Reti <gilad.reti@gmail.com> wrote: >>> >>> Add test to check that the verifier is able to recognize spilling of >>> PTR_TO_MEM registers. >> >> It would be nice to have some explanation of what the test does to >> recognize the spilling of the PTR_TO_MEM registers in the commit >> log as well. >> >> Would it be possible to augment an existing test_progs >> program like tools/testing/selftests/bpf/progs/test_ringbuf.c to test >> this functionality?
How would you guarantee that LLVM generates the spill/fill, via inline asm?
> It may be possible, but from what I understood from Daniel's comment here > > https://lore.kernel.org/bpf/17629073-4fab-a922-ecc3-25b019960f44@iogearbox.net/ > > the test should be a part of the verifier tests (which is reasonable > to me since it is > a verifier bugfix)
Yeah, the test_verifier case as you have is definitely the most straight forward way to add coverage in this case.
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