Re: [PATCH v3] MIPS/bpf: Enable bpf_probe_read{, str}() on MIPS again

From: Thomas Bogendoerfer
Date: Mon Mar 29 2021 - 05:31:18 EST


On Thu, Mar 25, 2021 at 08:50:01PM +0800, Tiezhu Yang wrote:
> After commit 0ebeea8ca8a4 ("bpf: Restrict bpf_probe_read{, str}() only to
> archs where they work"), bpf_probe_read{, str}() functions were no longer
> available on MIPS, so there exist some errors when running bpf program:
>
> root@linux:/home/loongson/bcc# python examples/tracing/task_switch.py
> bpf: Failed to load program: Invalid argument
> [...]
> 11: (85) call bpf_probe_read#4
> unknown func bpf_probe_read#4
> [...]
> Exception: Failed to load BPF program count_sched: Invalid argument
>
> ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE should be restricted to archs
> with non-overlapping address ranges, but they can overlap in EVA mode
> on MIPS, so select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE if !EVA in
> arch/mips/Kconfig, otherwise the bpf old helper bpf_probe_read() will
> not be available.
>
> This is similar with the commit d195b1d1d119 ("powerpc/bpf: Enable
> bpf_probe_read{, str}() on powerpc again").
>
> Fixes: 0ebeea8ca8a4 ("bpf: Restrict bpf_probe_read{, str}() only to archs where they work")
> Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
> ---
>
> v3: Select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE if !EVA
> on MIPS.
>
> v2: update the commit message to fix typos found by
> Sergei Shtylyov, thank you!
>
> not longer --> no longer
> there exists --> there exist
>
> arch/mips/Kconfig | 1 +
> 1 file changed, 1 insertion(+)

applied to mips-next.

Thomas.

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