On Thu, Nov 24, 2022 at 12:34 PM Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> wrote: > > On Wed, Nov 23, 2022 at 9:32 PM Yonghong Song <yhs@xxxxxx> wrote: > > > > @@ -16580,6 +16682,8 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr) > > env->bypass_spec_v1 = bpf_bypass_spec_v1(); > > env->bypass_spec_v4 = bpf_bypass_spec_v4(); > > env->bpf_capable = bpf_capable(); > > + env->rcu_tag_supported = > > + btf_find_by_name_kind(btf_vmlinux, "rcu", BTF_KIND_TYPE_TAG) > 0; > > It needs btf_vmlinux != NULL check as well, > since we error earlier only on IS_ERR(btf_vmlinux). > btf_vmlinux can be NULL at this point when CONFIG_DEBUG_INFO_BTF is not set. > > In the previous discussion I thought we agreed to > fix convert_ctx_accesses() vs incorrect application of > BPF_PROBE_MEM for PTR_TRUSTED pointers. > But I didn't find it in this patch. > So I'm fixing both issues and planning to apply after testing. Turned out the initial PTR_TRUSTED patch was buggy. prog_type_args_trusted() is incorrect. It marks fentry/fexit pointers as trusted and our own selftest is crashing. I'll send a separate fix. So going to apply rcu set with just btf_vmlinux fix.
