elf_reader: Add support for XDP frags #1037
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lmb
reviewed
May 16, 2023
| @@ -35,6 +35,7 @@ const ( | |||
| BPF_F_RDONLY_PROG = linux.BPF_F_RDONLY_PROG | |||
| BPF_F_WRONLY_PROG = linux.BPF_F_WRONLY_PROG | |||
| BPF_F_SLEEPABLE = linux.BPF_F_SLEEPABLE | |||
| BPF_F_XDP_HAS_FRAGS = linux.BPF_F_XDP_HAS_FRAGS | |||
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Can you add a dummy entry to types_other.go please?
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sorry about that, forgot to commit the change. fixed now
Since v5.18 of the Linux kernel, it is possible for an XDP program to process packets larger than the physical page of the system. This feature is called XDP frags. In order for an XDP program to signal that it can process packets with large MTUs, it needs to have the "xdp.frags" annotation instead of "xdp". This new annotation causes the BPF_F_XDP_HAS_FRAGS to be added to the annotated program section of the ELF. This flag in turn causes the verifier to apply extra checks to the code. The commit along with some documentation about the feature can be seen here: torvalds/linux@c2f2cdb This commit allows the code to parse the "xdp.frags" annotation and adds the appropriate flag to the program section, along with unit tests for this behaviour. It follows the functionality of this code: https://elixir.bootlin.com/linux/v6.0/source/tools/lib/bpf/libbpf.c#L6626 Signed-off-by: Pavlos Tzianos <pavlos@cloudflare.com>
lmb
approved these changes
May 17, 2023
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implements #1036
Since v5.18 of the Linux kernel, it is possible for an XDP program to process packets larger than the physical page of the system. This feature is called XDP frags.
In order for an XDP program to signal that it can process packets with large MTUs, it needs to have the "xdp.frags" annotation instead of "xdp". This new annotation causes the BPF_F_XDP_HAS_FRAGS to be added to the annotated program section of the ELF. This flag in turn causes the verifier to apply extra checks to the code. The commit along with some documentation about the feature can be seen here:
torvalds/linux@c2f2cdb
This commit allows the code to parse the "xdp.frags" annotation and adds the appropriate flag to the program section, along with unit tests for this behaviour. It replicated the functionality of this code: https://elixir.bootlin.com/linux/v6.0/source/tools/lib/bpf/libbpf.c#L6626