Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
authorJakub Kicinski <kuba@kernel.org>
Fri, 10 Dec 2021 23:56:10 +0000 (15:56 -0800)
committerJakub Kicinski <kuba@kernel.org>
Fri, 10 Dec 2021 23:56:13 +0000 (15:56 -0800)
Andrii Nakryiko says:

====================
bpf-next 2021-12-10 v2

We've added 115 non-merge commits during the last 26 day(s) which contain
a total of 182 files changed, 5747 insertions(+), 2564 deletions(-).

The main changes are:

1) Various samples fixes, from Alexander Lobakin.

2) BPF CO-RE support in kernel and light skeleton, from Alexei Starovoitov.

3) A batch of new unified APIs for libbpf, logging improvements, version
   querying, etc. Also a batch of old deprecations for old APIs and various
   bug fixes, in preparation for libbpf 1.0, from Andrii Nakryiko.

4) BPF documentation reorganization and improvements, from Christoph Hellwig
   and Dave Tucker.

5) Support for declarative initialization of BPF_MAP_TYPE_PROG_ARRAY in
   libbpf, from Hengqi Chen.

6) Verifier log fixes, from Hou Tao.

7) Runtime-bounded loops support with bpf_loop() helper, from Joanne Koong.

8) Extend branch record capturing to all platforms that support it,
   from Kajol Jain.

9) Light skeleton codegen improvements, from Kumar Kartikeya Dwivedi.

10) bpftool doc-generating script improvements, from Quentin Monnet.

11) Two libbpf v0.6 bug fixes, from Shuyi Cheng and Vincent Minet.

12) Deprecation warning fix for perf/bpf_counter, from Song Liu.

13) MAX_TAIL_CALL_CNT unification and MIPS build fix for libbpf,
    from Tiezhu Yang.

14) BTF_KING_TYPE_TAG follow-up fixes, from Yonghong Song.

15) Selftests fixes and improvements, from Ilya Leoshkevich, Jean-Philippe
    Brucker, Jiri Olsa, Maxim Mikityanskiy, Tirthendu Sarkar, Yucong Sun,
    and others.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (115 commits)
  libbpf: Add "bool skipped" to struct bpf_map
  libbpf: Fix typo in btf__dedup@LIBBPF_0.0.2 definition
  bpftool: Switch bpf_object__load_xattr() to bpf_object__load()
  selftests/bpf: Remove the only use of deprecated bpf_object__load_xattr()
  selftests/bpf: Add test for libbpf's custom log_buf behavior
  selftests/bpf: Replace all uses of bpf_load_btf() with bpf_btf_load()
  libbpf: Deprecate bpf_object__load_xattr()
  libbpf: Add per-program log buffer setter and getter
  libbpf: Preserve kernel error code and remove kprobe prog type guessing
  libbpf: Improve logging around BPF program loading
  libbpf: Allow passing user log setting through bpf_object_open_opts
  libbpf: Allow passing preallocated log_buf when loading BTF into kernel
  libbpf: Add OPTS-based bpf_btf_load() API
  libbpf: Fix bpf_prog_load() log_buf logic for log_level 0
  samples/bpf: Remove unneeded variable
  bpf: Remove redundant assignment to pointer t
  selftests/bpf: Fix a compilation warning
  perf/bpf_counter: Use bpf_map_create instead of bpf_create_map
  samples: bpf: Fix 'unknown warning group' build warning on Clang
  samples: bpf: Fix xdp_sample_user.o linking with Clang
  ...
====================

Link: https://lore.kernel.org/r/20211210234746.2100561-1-andrii@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
17 files changed:
1  2 
MAINTAINERS
include/linux/bpf.h
include/linux/btf.h
kernel/bpf/btf.c
kernel/bpf/helpers.c
kernel/bpf/syscall.c
kernel/bpf/verifier.c
kernel/trace/bpf_trace.c
net/core/filter.c
net/ipv4/bpf_tcp_ca.c
tools/bpf/resolve_btfids/main.c
tools/lib/bpf/bpf_gen_internal.h
tools/lib/bpf/gen_loader.c
tools/lib/bpf/libbpf.c
tools/perf/tests/bpf.c
tools/testing/selftests/bpf/Makefile
tools/testing/selftests/bpf/test_verifier.c

diff --cc MAINTAINERS
Simple merge
Simple merge
Simple merge
index 48cdf5b425a7fc989d5a9633e05c228bd2cccb78,27b7de5386977fd4e44f40412a8a679d090e17a9..8b00c6e4d6fb7f7c7a2a6e816aef3a1477816bc9
@@@ -6405,4 -6418,384 +6409,386 @@@ bool bpf_check_mod_kfunc_call(struct kf
  DEFINE_KFUNC_BTF_ID_LIST(bpf_tcp_ca_kfunc_list);
  DEFINE_KFUNC_BTF_ID_LIST(prog_test_kfunc_list);
  
 +#endif
++
+ int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id,
+                             const struct btf *targ_btf, __u32 targ_id)
+ {
+       return -EOPNOTSUPP;
+ }
+ static bool bpf_core_is_flavor_sep(const char *s)
+ {
+       /* check X___Y name pattern, where X and Y are not underscores */
+       return s[0] != '_' &&                                 /* X */
+              s[1] == '_' && s[2] == '_' && s[3] == '_' &&   /* ___ */
+              s[4] != '_';                                   /* Y */
+ }
+ size_t bpf_core_essential_name_len(const char *name)
+ {
+       size_t n = strlen(name);
+       int i;
+       for (i = n - 5; i >= 0; i--) {
+               if (bpf_core_is_flavor_sep(name + i))
+                       return i + 1;
+       }
+       return n;
+ }
+ struct bpf_cand_cache {
+       const char *name;
+       u32 name_len;
+       u16 kind;
+       u16 cnt;
+       struct {
+               const struct btf *btf;
+               u32 id;
+       } cands[];
+ };
+ static void bpf_free_cands(struct bpf_cand_cache *cands)
+ {
+       if (!cands->cnt)
+               /* empty candidate array was allocated on stack */
+               return;
+       kfree(cands);
+ }
+ static void bpf_free_cands_from_cache(struct bpf_cand_cache *cands)
+ {
+       kfree(cands->name);
+       kfree(cands);
+ }
+ #define VMLINUX_CAND_CACHE_SIZE 31
+ static struct bpf_cand_cache *vmlinux_cand_cache[VMLINUX_CAND_CACHE_SIZE];
+ #define MODULE_CAND_CACHE_SIZE 31
+ static struct bpf_cand_cache *module_cand_cache[MODULE_CAND_CACHE_SIZE];
+ static DEFINE_MUTEX(cand_cache_mutex);
+ static void __print_cand_cache(struct bpf_verifier_log *log,
+                              struct bpf_cand_cache **cache,
+                              int cache_size)
+ {
+       struct bpf_cand_cache *cc;
+       int i, j;
+       for (i = 0; i < cache_size; i++) {
+               cc = cache[i];
+               if (!cc)
+                       continue;
+               bpf_log(log, "[%d]%s(", i, cc->name);
+               for (j = 0; j < cc->cnt; j++) {
+                       bpf_log(log, "%d", cc->cands[j].id);
+                       if (j < cc->cnt - 1)
+                               bpf_log(log, " ");
+               }
+               bpf_log(log, "), ");
+       }
+ }
+ static void print_cand_cache(struct bpf_verifier_log *log)
+ {
+       mutex_lock(&cand_cache_mutex);
+       bpf_log(log, "vmlinux_cand_cache:");
+       __print_cand_cache(log, vmlinux_cand_cache, VMLINUX_CAND_CACHE_SIZE);
+       bpf_log(log, "\nmodule_cand_cache:");
+       __print_cand_cache(log, module_cand_cache, MODULE_CAND_CACHE_SIZE);
+       bpf_log(log, "\n");
+       mutex_unlock(&cand_cache_mutex);
+ }
+ static u32 hash_cands(struct bpf_cand_cache *cands)
+ {
+       return jhash(cands->name, cands->name_len, 0);
+ }
+ static struct bpf_cand_cache *check_cand_cache(struct bpf_cand_cache *cands,
+                                              struct bpf_cand_cache **cache,
+                                              int cache_size)
+ {
+       struct bpf_cand_cache *cc = cache[hash_cands(cands) % cache_size];
+       if (cc && cc->name_len == cands->name_len &&
+           !strncmp(cc->name, cands->name, cands->name_len))
+               return cc;
+       return NULL;
+ }
+ static size_t sizeof_cands(int cnt)
+ {
+       return offsetof(struct bpf_cand_cache, cands[cnt]);
+ }
+ static struct bpf_cand_cache *populate_cand_cache(struct bpf_cand_cache *cands,
+                                                 struct bpf_cand_cache **cache,
+                                                 int cache_size)
+ {
+       struct bpf_cand_cache **cc = &cache[hash_cands(cands) % cache_size], *new_cands;
+       if (*cc) {
+               bpf_free_cands_from_cache(*cc);
+               *cc = NULL;
+       }
+       new_cands = kmalloc(sizeof_cands(cands->cnt), GFP_KERNEL);
+       if (!new_cands) {
+               bpf_free_cands(cands);
+               return ERR_PTR(-ENOMEM);
+       }
+       memcpy(new_cands, cands, sizeof_cands(cands->cnt));
+       /* strdup the name, since it will stay in cache.
+        * the cands->name points to strings in prog's BTF and the prog can be unloaded.
+        */
+       new_cands->name = kmemdup_nul(cands->name, cands->name_len, GFP_KERNEL);
+       bpf_free_cands(cands);
+       if (!new_cands->name) {
+               kfree(new_cands);
+               return ERR_PTR(-ENOMEM);
+       }
+       *cc = new_cands;
+       return new_cands;
+ }
+ #ifdef CONFIG_DEBUG_INFO_BTF_MODULES
+ static void __purge_cand_cache(struct btf *btf, struct bpf_cand_cache **cache,
+                              int cache_size)
+ {
+       struct bpf_cand_cache *cc;
+       int i, j;
+       for (i = 0; i < cache_size; i++) {
+               cc = cache[i];
+               if (!cc)
+                       continue;
+               if (!btf) {
+                       /* when new module is loaded purge all of module_cand_cache,
+                        * since new module might have candidates with the name
+                        * that matches cached cands.
+                        */
+                       bpf_free_cands_from_cache(cc);
+                       cache[i] = NULL;
+                       continue;
+               }
+               /* when module is unloaded purge cache entries
+                * that match module's btf
+                */
+               for (j = 0; j < cc->cnt; j++)
+                       if (cc->cands[j].btf == btf) {
+                               bpf_free_cands_from_cache(cc);
+                               cache[i] = NULL;
+                               break;
+                       }
+       }
+ }
+ static void purge_cand_cache(struct btf *btf)
+ {
+       mutex_lock(&cand_cache_mutex);
+       __purge_cand_cache(btf, module_cand_cache, MODULE_CAND_CACHE_SIZE);
+       mutex_unlock(&cand_cache_mutex);
+ }
+ #endif
+ static struct bpf_cand_cache *
+ bpf_core_add_cands(struct bpf_cand_cache *cands, const struct btf *targ_btf,
+                  int targ_start_id)
+ {
+       struct bpf_cand_cache *new_cands;
+       const struct btf_type *t;
+       const char *targ_name;
+       size_t targ_essent_len;
+       int n, i;
+       n = btf_nr_types(targ_btf);
+       for (i = targ_start_id; i < n; i++) {
+               t = btf_type_by_id(targ_btf, i);
+               if (btf_kind(t) != cands->kind)
+                       continue;
+               targ_name = btf_name_by_offset(targ_btf, t->name_off);
+               if (!targ_name)
+                       continue;
+               /* the resched point is before strncmp to make sure that search
+                * for non-existing name will have a chance to schedule().
+                */
+               cond_resched();
+               if (strncmp(cands->name, targ_name, cands->name_len) != 0)
+                       continue;
+               targ_essent_len = bpf_core_essential_name_len(targ_name);
+               if (targ_essent_len != cands->name_len)
+                       continue;
+               /* most of the time there is only one candidate for a given kind+name pair */
+               new_cands = kmalloc(sizeof_cands(cands->cnt + 1), GFP_KERNEL);
+               if (!new_cands) {
+                       bpf_free_cands(cands);
+                       return ERR_PTR(-ENOMEM);
+               }
+               memcpy(new_cands, cands, sizeof_cands(cands->cnt));
+               bpf_free_cands(cands);
+               cands = new_cands;
+               cands->cands[cands->cnt].btf = targ_btf;
+               cands->cands[cands->cnt].id = i;
+               cands->cnt++;
+       }
+       return cands;
+ }
+ static struct bpf_cand_cache *
+ bpf_core_find_cands(struct bpf_core_ctx *ctx, u32 local_type_id)
+ {
+       struct bpf_cand_cache *cands, *cc, local_cand = {};
+       const struct btf *local_btf = ctx->btf;
+       const struct btf_type *local_type;
+       const struct btf *main_btf;
+       size_t local_essent_len;
+       struct btf *mod_btf;
+       const char *name;
+       int id;
+       main_btf = bpf_get_btf_vmlinux();
+       if (IS_ERR(main_btf))
+               return (void *)main_btf;
+       local_type = btf_type_by_id(local_btf, local_type_id);
+       if (!local_type)
+               return ERR_PTR(-EINVAL);
+       name = btf_name_by_offset(local_btf, local_type->name_off);
+       if (str_is_empty(name))
+               return ERR_PTR(-EINVAL);
+       local_essent_len = bpf_core_essential_name_len(name);
+       cands = &local_cand;
+       cands->name = name;
+       cands->kind = btf_kind(local_type);
+       cands->name_len = local_essent_len;
+       cc = check_cand_cache(cands, vmlinux_cand_cache, VMLINUX_CAND_CACHE_SIZE);
+       /* cands is a pointer to stack here */
+       if (cc) {
+               if (cc->cnt)
+                       return cc;
+               goto check_modules;
+       }
+       /* Attempt to find target candidates in vmlinux BTF first */
+       cands = bpf_core_add_cands(cands, main_btf, 1);
+       if (IS_ERR(cands))
+               return cands;
+       /* cands is a pointer to kmalloced memory here if cands->cnt > 0 */
+       /* populate cache even when cands->cnt == 0 */
+       cc = populate_cand_cache(cands, vmlinux_cand_cache, VMLINUX_CAND_CACHE_SIZE);
+       if (IS_ERR(cc))
+               return cc;
+       /* if vmlinux BTF has any candidate, don't go for module BTFs */
+       if (cc->cnt)
+               return cc;
+ check_modules:
+       /* cands is a pointer to stack here and cands->cnt == 0 */
+       cc = check_cand_cache(cands, module_cand_cache, MODULE_CAND_CACHE_SIZE);
+       if (cc)
+               /* if cache has it return it even if cc->cnt == 0 */
+               return cc;
+       /* If candidate is not found in vmlinux's BTF then search in module's BTFs */
+       spin_lock_bh(&btf_idr_lock);
+       idr_for_each_entry(&btf_idr, mod_btf, id) {
+               if (!btf_is_module(mod_btf))
+                       continue;
+               /* linear search could be slow hence unlock/lock
+                * the IDR to avoiding holding it for too long
+                */
+               btf_get(mod_btf);
+               spin_unlock_bh(&btf_idr_lock);
+               cands = bpf_core_add_cands(cands, mod_btf, btf_nr_types(main_btf));
+               if (IS_ERR(cands)) {
+                       btf_put(mod_btf);
+                       return cands;
+               }
+               spin_lock_bh(&btf_idr_lock);
+               btf_put(mod_btf);
+       }
+       spin_unlock_bh(&btf_idr_lock);
+       /* cands is a pointer to kmalloced memory here if cands->cnt > 0
+        * or pointer to stack if cands->cnd == 0.
+        * Copy it into the cache even when cands->cnt == 0 and
+        * return the result.
+        */
+       return populate_cand_cache(cands, module_cand_cache, MODULE_CAND_CACHE_SIZE);
+ }
+ int bpf_core_apply(struct bpf_core_ctx *ctx, const struct bpf_core_relo *relo,
+                  int relo_idx, void *insn)
+ {
+       bool need_cands = relo->kind != BPF_CORE_TYPE_ID_LOCAL;
+       struct bpf_core_cand_list cands = {};
+       struct bpf_core_spec *specs;
+       int err;
+       /* ~4k of temp memory necessary to convert LLVM spec like "0:1:0:5"
+        * into arrays of btf_ids of struct fields and array indices.
+        */
+       specs = kcalloc(3, sizeof(*specs), GFP_KERNEL);
+       if (!specs)
+               return -ENOMEM;
+       if (need_cands) {
+               struct bpf_cand_cache *cc;
+               int i;
+               mutex_lock(&cand_cache_mutex);
+               cc = bpf_core_find_cands(ctx, relo->type_id);
+               if (IS_ERR(cc)) {
+                       bpf_log(ctx->log, "target candidate search failed for %d\n",
+                               relo->type_id);
+                       err = PTR_ERR(cc);
+                       goto out;
+               }
+               if (cc->cnt) {
+                       cands.cands = kcalloc(cc->cnt, sizeof(*cands.cands), GFP_KERNEL);
+                       if (!cands.cands) {
+                               err = -ENOMEM;
+                               goto out;
+                       }
+               }
+               for (i = 0; i < cc->cnt; i++) {
+                       bpf_log(ctx->log,
+                               "CO-RE relocating %s %s: found target candidate [%d]\n",
+                               btf_kind_str[cc->kind], cc->name, cc->cands[i].id);
+                       cands.cands[i].btf = cc->cands[i].btf;
+                       cands.cands[i].id = cc->cands[i].id;
+               }
+               cands.len = cc->cnt;
+               /* cand_cache_mutex needs to span the cache lookup and
+                * copy of btf pointer into bpf_core_cand_list,
+                * since module can be unloaded while bpf_core_apply_relo_insn
+                * is working with module's btf.
+                */
+       }
+       err = bpf_core_apply_relo_insn((void *)ctx->log, insn, relo->insn_off / 8,
+                                      relo, relo_idx, ctx->btf, &cands, specs);
+ out:
+       kfree(specs);
+       if (need_cands) {
+               kfree(cands.cands);
+               mutex_unlock(&cand_cache_mutex);
+               if (ctx->log->level & BPF_LOG_LEVEL2)
+                       print_cand_cache(ctx->log);
+       }
+       return err;
+ }
Simple merge
Simple merge
Simple merge
Simple merge
Simple merge
Simple merge
Simple merge
index cc486a77db651359a86b9c8cdce1aed6e61d570c,9dd5f76692ef02b8aa11ffa2487b624e51795d10..223308931d559679ccbfd38fecf5d562d77f65e4
@@@ -47,11 -49,14 +49,14 @@@ struct bpf_gen 
        int nr_fd_array;
  };
  
 -void bpf_gen__init(struct bpf_gen *gen, int log_level);
 -int bpf_gen__finish(struct bpf_gen *gen);
 +void bpf_gen__init(struct bpf_gen *gen, int log_level, int nr_progs, int nr_maps);
 +int bpf_gen__finish(struct bpf_gen *gen, int nr_progs, int nr_maps);
  void bpf_gen__free(struct bpf_gen *gen);
  void bpf_gen__load_btf(struct bpf_gen *gen, const void *raw_data, __u32 raw_size);
- void bpf_gen__map_create(struct bpf_gen *gen, struct bpf_create_map_params *map_attr, int map_idx);
+ void bpf_gen__map_create(struct bpf_gen *gen,
+                        enum bpf_map_type map_type, const char *map_name,
+                        __u32 key_size, __u32 value_size, __u32 max_entries,
+                        struct bpf_map_create_opts *map_attr, int map_idx);
  void bpf_gen__prog_load(struct bpf_gen *gen,
                        enum bpf_prog_type prog_type, const char *prog_name,
                        const char *license, struct bpf_insn *insns, size_t insn_cnt,
Simple merge
index f6faa33c80fa78ba1d8da5ebd884bd399b0916eb,d027e1d620fc11973439bae9c3b4531180053696..902f1ad5b7e67a7f0a2b6fa231edc7987fbe4801
@@@ -7263,7 -7477,7 +7477,7 @@@ static int bpf_object_load(struct bpf_o
        }
  
        if (obj->gen_loader)
-               bpf_gen__init(obj->gen_loader, attr->log_level, obj->nr_programs, obj->nr_maps);
 -              bpf_gen__init(obj->gen_loader, extra_log_level);
++              bpf_gen__init(obj->gen_loader, extra_log_level, obj->nr_programs, obj->nr_maps);
  
        err = bpf_object__probe_loading(obj);
        err = err ? : bpf_object__load_vmlinux_btf(obj, false);
index 329f77f592f421bd4427a3c1287ef46b9f88586e,c52bf10f746ed166d1b9e9c414e08cb8421b0631..573490530194f8c2dd0c755c3524cba39b05f1f2
@@@ -296,9 -312,13 +296,13 @@@ static int check_env(void
                return err;
        }
  
+ /* temporarily disable libbpf deprecation warnings */
+ #pragma GCC diagnostic push
+ #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
        err = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns,
 -                             sizeof(insns) / sizeof(insns[0]),
 +                             ARRAY_SIZE(insns),
                               license, kver_int, NULL, 0);
+ #pragma GCC diagnostic pop
        if (err < 0) {
                pr_err("Missing basic BPF support, skip this test: %s\n",
                       strerror(errno));
Simple merge