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ci: Temporarily apply tools/resolve_btfids cross-compilation fix for …
…bpf tree https://lore.kernel.org/all/[email protected]/ is not pulled into bpf tree yet. Add the patch in the meantime. Signed-off-by: Manu Bretelle <[email protected]>
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ci/diffs/0001-tools-resolve_btfids-fix-cross-compilation-to-non-host-endianness.patch
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| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,256 @@ | ||
| From 9707ac4fe2f5bac6406d2403f8b8a64d7b3d8e43 Mon Sep 17 00:00:00 2001 | ||
| From: Viktor Malik <[email protected]> | ||
| Date: Tue, 6 Feb 2024 13:46:09 +0100 | ||
| Subject: tools/resolve_btfids: Refactor set sorting with types from btf_ids.h | ||
|
|
||
| Instead of using magic offsets to access BTF ID set data, leverage types | ||
| from btf_ids.h (btf_id_set and btf_id_set8) which define the actual | ||
| layout of the data. Thanks to this change, set sorting should also | ||
| continue working if the layout changes. | ||
|
|
||
| This requires to sync the definition of 'struct btf_id_set8' from | ||
| include/linux/btf_ids.h to tools/include/linux/btf_ids.h. We don't sync | ||
| the rest of the file at the moment, b/c that would require to also sync | ||
| multiple dependent headers and we don't need any other defs from | ||
| btf_ids.h. | ||
|
|
||
| Signed-off-by: Viktor Malik <[email protected]> | ||
| Signed-off-by: Andrii Nakryiko <[email protected]> | ||
| Acked-by: Daniel Xu <[email protected]> | ||
| Link: https://lore.kernel.org/bpf/ff7f062ddf6a00815fda3087957c4ce667f50532.1707223196.git.vmalik@redhat.com | ||
| --- | ||
| tools/bpf/resolve_btfids/main.c | 35 +++++++++++++++++++++-------------- | ||
| tools/include/linux/btf_ids.h | 9 +++++++++ | ||
| 2 files changed, 30 insertions(+), 14 deletions(-) | ||
|
|
||
| diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c | ||
| index 27a23196d58e10..32634f00abba4a 100644 | ||
| --- a/tools/bpf/resolve_btfids/main.c | ||
| +++ b/tools/bpf/resolve_btfids/main.c | ||
| @@ -70,6 +70,7 @@ | ||
| #include <sys/stat.h> | ||
| #include <fcntl.h> | ||
| #include <errno.h> | ||
| +#include <linux/btf_ids.h> | ||
| #include <linux/rbtree.h> | ||
| #include <linux/zalloc.h> | ||
| #include <linux/err.h> | ||
| @@ -78,7 +79,7 @@ | ||
| #include <subcmd/parse-options.h> | ||
|
|
||
| #define BTF_IDS_SECTION ".BTF_ids" | ||
| -#define BTF_ID "__BTF_ID__" | ||
| +#define BTF_ID_PREFIX "__BTF_ID__" | ||
|
|
||
| #define BTF_STRUCT "struct" | ||
| #define BTF_UNION "union" | ||
| @@ -161,7 +162,7 @@ static int eprintf(int level, int var, const char *fmt, ...) | ||
|
|
||
| static bool is_btf_id(const char *name) | ||
| { | ||
| - return name && !strncmp(name, BTF_ID, sizeof(BTF_ID) - 1); | ||
| + return name && !strncmp(name, BTF_ID_PREFIX, sizeof(BTF_ID_PREFIX) - 1); | ||
| } | ||
|
|
||
| static struct btf_id *btf_id__find(struct rb_root *root, const char *name) | ||
| @@ -441,7 +442,7 @@ static int symbols_collect(struct object *obj) | ||
| * __BTF_ID__TYPE__vfs_truncate__0 | ||
| * prefix = ^ | ||
| */ | ||
| - prefix = name + sizeof(BTF_ID) - 1; | ||
| + prefix = name + sizeof(BTF_ID_PREFIX) - 1; | ||
|
|
||
| /* struct */ | ||
| if (!strncmp(prefix, BTF_STRUCT, sizeof(BTF_STRUCT) - 1)) { | ||
| @@ -649,19 +650,18 @@ static int cmp_id(const void *pa, const void *pb) | ||
| static int sets_patch(struct object *obj) | ||
| { | ||
| Elf_Data *data = obj->efile.idlist; | ||
| - int *ptr = data->d_buf; | ||
| struct rb_node *next; | ||
|
|
||
| next = rb_first(&obj->sets); | ||
| while (next) { | ||
| - unsigned long addr, idx; | ||
| + struct btf_id_set8 *set8; | ||
| + struct btf_id_set *set; | ||
| + unsigned long addr, off; | ||
| struct btf_id *id; | ||
| - int *base; | ||
| - int cnt; | ||
|
|
||
| id = rb_entry(next, struct btf_id, rb_node); | ||
| addr = id->addr[0]; | ||
| - idx = addr - obj->efile.idlist_addr; | ||
| + off = addr - obj->efile.idlist_addr; | ||
|
|
||
| /* sets are unique */ | ||
| if (id->addr_cnt != 1) { | ||
| @@ -670,14 +670,21 @@ static int sets_patch(struct object *obj) | ||
| return -1; | ||
| } | ||
|
|
||
| - idx = idx / sizeof(int); | ||
| - base = &ptr[idx] + (id->is_set8 ? 2 : 1); | ||
| - cnt = ptr[idx]; | ||
| + if (id->is_set) { | ||
| + set = data->d_buf + off; | ||
| + qsort(set->ids, set->cnt, sizeof(set->ids[0]), cmp_id); | ||
| + } else { | ||
| + set8 = data->d_buf + off; | ||
| + /* | ||
| + * Make sure id is at the beginning of the pairs | ||
| + * struct, otherwise the below qsort would not work. | ||
| + */ | ||
| + BUILD_BUG_ON(set8->pairs != &set8->pairs[0].id); | ||
| + qsort(set8->pairs, set8->cnt, sizeof(set8->pairs[0]), cmp_id); | ||
| + } | ||
|
|
||
| pr_debug("sorting addr %5lu: cnt %6d [%s]\n", | ||
| - (idx + 1) * sizeof(int), cnt, id->name); | ||
| - | ||
| - qsort(base, cnt, id->is_set8 ? sizeof(uint64_t) : sizeof(int), cmp_id); | ||
| + off, id->is_set ? set->cnt : set8->cnt, id->name); | ||
|
|
||
| next = rb_next(next); | ||
| } | ||
| diff --git a/tools/include/linux/btf_ids.h b/tools/include/linux/btf_ids.h | ||
| index 2f882d5cb30f5c..72535f00572f6e 100644 | ||
| --- a/tools/include/linux/btf_ids.h | ||
| +++ b/tools/include/linux/btf_ids.h | ||
| @@ -8,6 +8,15 @@ struct btf_id_set { | ||
| u32 ids[]; | ||
| }; | ||
|
|
||
| +struct btf_id_set8 { | ||
| + u32 cnt; | ||
| + u32 flags; | ||
| + struct { | ||
| + u32 id; | ||
| + u32 flags; | ||
| + } pairs[]; | ||
| +}; | ||
| + | ||
| #ifdef CONFIG_DEBUG_INFO_BTF | ||
|
|
||
| #include <linux/compiler.h> /* for __PASTE */ | ||
| -- | ||
| cgit 1.2.3-korg | ||
|
|
||
|
|
||
| From 903fad4394666bc23975c93fb58f137ce64b5192 Mon Sep 17 00:00:00 2001 | ||
| From: Viktor Malik <[email protected]> | ||
| Date: Tue, 6 Feb 2024 13:46:10 +0100 | ||
| Subject: tools/resolve_btfids: Fix cross-compilation to non-host endianness | ||
|
|
||
| The .BTF_ids section is pre-filled with zeroed BTF ID entries during the | ||
| build and afterwards patched by resolve_btfids with correct values. | ||
| Since resolve_btfids always writes in host-native endianness, it relies | ||
| on libelf to do the translation when the target ELF is cross-compiled to | ||
| a different endianness (this was introduced in commit 61e8aeda9398 | ||
| ("bpf: Fix libelf endian handling in resolv_btfids")). | ||
|
|
||
| Unfortunately, the translation will corrupt the flags fields of SET8 | ||
| entries because these were written during vmlinux compilation and are in | ||
| the correct endianness already. This will lead to numerous selftests | ||
| failures such as: | ||
|
|
||
| $ sudo ./test_verifier 502 502 | ||
| #502/p sleepable fentry accept FAIL | ||
| Failed to load prog 'Invalid argument'! | ||
| bpf_fentry_test1 is not sleepable | ||
| verification time 34 usec | ||
| stack depth 0 | ||
| processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 | ||
| Summary: 0 PASSED, 0 SKIPPED, 1 FAILED | ||
|
|
||
| Since it's not possible to instruct libelf to translate just certain | ||
| values, let's manually bswap the flags (both global and entry flags) in | ||
| resolve_btfids when needed, so that libelf then translates everything | ||
| correctly. | ||
|
|
||
| Fixes: ef2c6f370a63 ("tools/resolve_btfids: Add support for 8-byte BTF sets") | ||
| Signed-off-by: Viktor Malik <[email protected]> | ||
| Signed-off-by: Andrii Nakryiko <[email protected]> | ||
| Link: https://lore.kernel.org/bpf/7b6bff690919555574ce0f13d2a5996cacf7bf69.1707223196.git.vmalik@redhat.com | ||
| --- | ||
| tools/bpf/resolve_btfids/main.c | 35 +++++++++++++++++++++++++++++++++++ | ||
| 1 file changed, 35 insertions(+) | ||
|
|
||
| diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c | ||
| index 32634f00abba4a..d9520cb826b31f 100644 | ||
| --- a/tools/bpf/resolve_btfids/main.c | ||
| +++ b/tools/bpf/resolve_btfids/main.c | ||
| @@ -90,6 +90,14 @@ | ||
|
|
||
| #define ADDR_CNT 100 | ||
|
|
||
| +#if __BYTE_ORDER == __LITTLE_ENDIAN | ||
| +# define ELFDATANATIVE ELFDATA2LSB | ||
| +#elif __BYTE_ORDER == __BIG_ENDIAN | ||
| +# define ELFDATANATIVE ELFDATA2MSB | ||
| +#else | ||
| +# error "Unknown machine endianness!" | ||
| +#endif | ||
| + | ||
| struct btf_id { | ||
| struct rb_node rb_node; | ||
| char *name; | ||
| @@ -117,6 +125,7 @@ struct object { | ||
| int idlist_shndx; | ||
| size_t strtabidx; | ||
| unsigned long idlist_addr; | ||
| + int encoding; | ||
| } efile; | ||
|
|
||
| struct rb_root sets; | ||
| @@ -320,6 +329,7 @@ static int elf_collect(struct object *obj) | ||
| { | ||
| Elf_Scn *scn = NULL; | ||
| size_t shdrstrndx; | ||
| + GElf_Ehdr ehdr; | ||
| int idx = 0; | ||
| Elf *elf; | ||
| int fd; | ||
| @@ -351,6 +361,13 @@ static int elf_collect(struct object *obj) | ||
| return -1; | ||
| } | ||
|
|
||
| + if (gelf_getehdr(obj->efile.elf, &ehdr) == NULL) { | ||
| + pr_err("FAILED cannot get ELF header: %s\n", | ||
| + elf_errmsg(-1)); | ||
| + return -1; | ||
| + } | ||
| + obj->efile.encoding = ehdr.e_ident[EI_DATA]; | ||
| + | ||
| /* | ||
| * Scan all the elf sections and look for save data | ||
| * from .BTF_ids section and symbols. | ||
| @@ -681,6 +698,24 @@ static int sets_patch(struct object *obj) | ||
| */ | ||
| BUILD_BUG_ON(set8->pairs != &set8->pairs[0].id); | ||
| qsort(set8->pairs, set8->cnt, sizeof(set8->pairs[0]), cmp_id); | ||
| + | ||
| + /* | ||
| + * When ELF endianness does not match endianness of the | ||
| + * host, libelf will do the translation when updating | ||
| + * the ELF. This, however, corrupts SET8 flags which are | ||
| + * already in the target endianness. So, let's bswap | ||
| + * them to the host endianness and libelf will then | ||
| + * correctly translate everything. | ||
| + */ | ||
| + if (obj->efile.encoding != ELFDATANATIVE) { | ||
| + int i; | ||
| + | ||
| + set8->flags = bswap_32(set8->flags); | ||
| + for (i = 0; i < set8->cnt; i++) { | ||
| + set8->pairs[i].flags = | ||
| + bswap_32(set8->pairs[i].flags); | ||
| + } | ||
| + } | ||
| } | ||
|
|
||
| pr_debug("sorting addr %5lu: cnt %6d [%s]\n", | ||
| -- | ||
| cgit 1.2.3-korg | ||
|
|