Changes in Kconfig

cb80ddc6 - bpf: Convert bpf_preload.ko to use light skeleton.

Wed, 09 Feb 2022 23:20:01 +0000

bpf: Convert bpf_preload.ko to use light skeleton.The main change is a move of the single line #include "iterators.lskel.h"from iterators/iterators.c to bpf_preload_kern.c.Which means that generated light skeleton can be used from user space oruser mode driver like iterators.c or from the kernel module or the kernel itself.The direct use of light skeleton from the kernel module simplifies the code,since UMD is no longer necessary. The libbpf.a required user space and UMD. TheCO-RE in the kernel and generated "loader bpf program" used by the lightskeleton are capable to perform complex loading operations traditionallyprovided by libbpf. In addition UMD approach was launching UMD processevery time bpffs has to be mounted. With light skeleton in the kernelthe bpf_preload kernel module loads bpf iterators once and pins themmultiple times into different bpffs mounts.Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220209232001.27490-6-alexei.starovoitov@gmail.com List of files: /linux-6.15/kernel/bpf/preload/Kconfig

7c0afcad - bpf: BPF_PRELOAD depends on BPF_SYSCALL

Thu, 05 Nov 2020 19:51:09 +0000

bpf: BPF_PRELOAD depends on BPF_SYSCALLFix build error when BPF_SYSCALL is not set/enabled but BPF_PRELOAD isby making BPF_PRELOAD depend on BPF_SYSCALL.ERROR: modpost: "bpf_preload_ops" [kernel/bpf/preload/bpf_preload.ko] undefined!Reported-by: kernel test robot Reported-by: Randy Dunlap Signed-off-by: Randy Dunlap Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20201105195109.26232-1-rdunlap@infradead.org List of files: /linux-6.15/kernel/bpf/preload/Kconfig

2532f849 - bpf: Disallow BPF_PRELOAD in allmodconfig builds

Tue, 25 Aug 2020 22:23:46 +0000

bpf: Disallow BPF_PRELOAD in allmodconfig buildsThe CC_CAN_LINK checks that the host compiler can link, but bpf_preloadrelies on libbpf which in turn needs libelf to be present during linking.allmodconfig runs in odd setups with cross compilers and missing hostlibraries like libelf. Instead of extending kconfig with every possiblelibrary that bpf_preload might need disallow building BPF_PRELOAD insuch build-only configurations.Signed-off-by: Alexei Starovoitov List of files: /linux-6.15/kernel/bpf/preload/Kconfig

d71fa5c9 - bpf: Add kernel module with user mode driver that populates bpffs.

Wed, 19 Aug 2020 04:27:58 +0000

bpf: Add kernel module with user mode driver that populates bpffs.Add kernel module with user mode driver that populates bpffs withBPF iterators.$ mount bpffs /my/bpffs/ -t bpf$ ls -la /my/bpffs/total 4drwxrwxrwt 2 root root 0 Jul 2 00:27 .drwxr-xr-x 19 root root 4096 Jul 2 00:09 ..-rw------- 1 root root 0 Jul 2 00:27 maps.debug-rw------- 1 root root 0 Jul 2 00:27 progs.debugThe user mode driver will load BPF Type Formats, create BPF maps, populate BPFmaps, load two BPF programs, attach them to BPF iterators, and finally send twobpf_link IDs back to the kernel.The kernel will pin two bpf_links into newly mounted bpffs instance undernames "progs.debug" and "maps.debug". These two files become human readable.$ cat /my/bpffs/progs.debug id name attached 11 dump_bpf_map bpf_iter_bpf_map 12 dump_bpf_prog bpf_iter_bpf_prog 27 test_pkt_access 32 test_main test_pkt_access test_pkt_access 33 test_subprog1 test_pkt_access_subprog1 test_pkt_access 34 test_subprog2 test_pkt_access_subprog2 test_pkt_access 35 test_subprog3 test_pkt_access_subprog3 test_pkt_access 36 new_get_skb_len get_skb_len test_pkt_access 37 new_get_skb_ifindex get_skb_ifindex test_pkt_access 38 new_get_constant get_constant test_pkt_accessThe BPF program dump_bpf_prog() in iterators.bpf.c is printing this data aboutall BPF programs currently loaded in the system. This information is unstableand will change from kernel to kernel as ".debug" suffix conveys.Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200819042759.51280-4-alexei.starovoitov@gmail.com List of files: /linux-6.15/kernel/bpf/preload/Kconfig