Merge branch 'core_reloc fixes for s390'

Ilya Leoshkevich says:

====================

v2: https://lore.kernel.org/bpf/20211025131214.731972-1-iii@linux.ibm.com/
v2 -> v3: Split the fix from the cleanup (Daniel).

v1: https://lore.kernel.org/bpf/20211021234653.643302-1-iii@linux.ibm.com/
v1 -> v2: Drop bpf_core_calc_field_relo() restructuring, split the
          __BYTE_ORDER__ change (Andrii).

Hi,

this series fixes test failures in core_reloc on s390.

Patch 1 fixes an endianness bug with __BYTE_ORDER vs __BYTE_ORDER__.
Patches 2-5 make the rest of the code consistent in that respect.
Patch 6 fixes an endianness issue in test_core_reloc_mods.

Best regards,
Ilya
====================
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

samples/seccomp/bpf-helper.h

@@ -62,9 +62,9 @@ void seccomp_bpf_print(struct sock_filter *filter, size_t count);
 #define EXPAND(...) __VA_ARGS__
 
 /* Ensure that we load the logically correct offset. */
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 #define LO_ARG(idx) offsetof(struct seccomp_data, args[(idx)])
-#elif __BYTE_ORDER == __BIG_ENDIAN
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 #define LO_ARG(idx) offsetof(struct seccomp_data, args[(idx)]) + sizeof(__u32)
 #else
 #error "Unknown endianness"
@@ -85,10 +85,10 @@ void seccomp_bpf_print(struct sock_filter *filter, size_t count);
 #elif __BITS_PER_LONG == 64
 
 /* Ensure that we load the logically correct offset. */
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 #define ENDIAN(_lo, _hi) _lo, _hi
 #define HI_ARG(idx) offsetof(struct seccomp_data, args[(idx)]) + sizeof(__u32)
-#elif __BYTE_ORDER == __BIG_ENDIAN
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 #define ENDIAN(_lo, _hi) _hi, _lo
 #define HI_ARG(idx) offsetof(struct seccomp_data, args[(idx)])
 #endif

tools/lib/bpf/bpf_core_read.h

@@ -40,7 +40,7 @@ enum bpf_enum_value_kind {
 #define __CORE_RELO(src, field, info)					      \
 	__builtin_preserve_field_info((src)->field, BPF_FIELD_##info)
 
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 #define __CORE_BITFIELD_PROBE_READ(dst, src, fld)			      \
 	bpf_probe_read_kernel(						      \
 			(void *)dst,				      \

tools/lib/bpf/btf.c

@@ -538,9 +538,9 @@ int btf__set_pointer_size(struct btf *btf, size_t ptr_sz)
 
 static bool is_host_big_endian(void)
 {
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	return false;
-#elif __BYTE_ORDER == __BIG_ENDIAN
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 	return true;
 #else
 # error "Unrecognized __BYTE_ORDER__"

tools/lib/bpf/btf_dump.c

@@ -1576,11 +1576,11 @@ static int btf_dump_get_bitfield_value(struct btf_dump *d,
 	/* Bitfield value retrieval is done in two steps; first relevant bytes are
 	 * stored in num, then we left/right shift num to eliminate irrelevant bits.
 	 */
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	for (i = t->size - 1; i >= 0; i--)
 		num = num * 256 + bytes[i];
 	nr_copy_bits = bit_sz + bits_offset;
-#elif __BYTE_ORDER == __BIG_ENDIAN
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 	for (i = 0; i < t->size; i++)
 		num = num * 256 + bytes[i];
 	nr_copy_bits = t->size * 8 - bits_offset;
@@ -1700,10 +1700,10 @@ static int btf_dump_int_data(struct btf_dump *d,
 		/* avoid use of __int128 as some 32-bit platforms do not
 		 * support it.
 		 */
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 		lsi = ints[0];
 		msi = ints[1];
-#elif __BYTE_ORDER == __BIG_ENDIAN
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 		lsi = ints[1];
 		msi = ints[0];
 #else

tools/lib/bpf/libbpf.c

@@ -1299,10 +1299,10 @@ static int bpf_object__elf_init(struct bpf_object *obj)
 
 static int bpf_object__check_endianness(struct bpf_object *obj)
 {
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	if (obj->efile.ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
 		return 0;
-#elif __BYTE_ORDER == __BIG_ENDIAN
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 	if (obj->efile.ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
 		return 0;
 #else

tools/lib/bpf/linker.c

@@ -323,12 +323,12 @@ static int init_output_elf(struct bpf_linker *linker, const char *file)
 
 	linker->elf_hdr->e_machine = EM_BPF;
 	linker->elf_hdr->e_type = ET_REL;
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	linker->elf_hdr->e_ident[EI_DATA] = ELFDATA2LSB;
-#elif __BYTE_ORDER == __BIG_ENDIAN
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 	linker->elf_hdr->e_ident[EI_DATA] = ELFDATA2MSB;
 #else
-#error "Unknown __BYTE_ORDER"
+#error "Unknown __BYTE_ORDER__"
 #endif
 
 	/* STRTAB */
@@ -538,12 +538,12 @@ static int linker_load_obj_file(struct bpf_linker *linker, const char *filename,
 				const struct bpf_linker_file_opts *opts,
 				struct src_obj *obj)
 {
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	const int host_endianness = ELFDATA2LSB;
-#elif __BYTE_ORDER == __BIG_ENDIAN
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 	const int host_endianness = ELFDATA2MSB;
 #else
-#error "Unknown __BYTE_ORDER"
+#error "Unknown __BYTE_ORDER__"
 #endif
 	int err = 0;
 	Elf_Scn *scn;

tools/lib/bpf/relo_core.c

@@ -662,7 +662,7 @@ static int bpf_core_calc_field_relo(const char *prog_name,
 			*validate = true; /* signedness is never ambiguous */
 		break;
 	case BPF_FIELD_LSHIFT_U64:
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 		*val = 64 - (bit_off + bit_sz - byte_off  * 8);
 #else
 		*val = (8 - byte_sz) * 8 + (bit_off - byte_off * 8);

tools/testing/selftests/bpf/prog_tests/btf_endian.c

@@ -7,12 +7,12 @@
 #include <bpf/btf.h>
 
 void test_btf_endian() {
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	enum btf_endianness endian = BTF_LITTLE_ENDIAN;
-#elif __BYTE_ORDER == __BIG_ENDIAN
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 	enum btf_endianness endian = BTF_BIG_ENDIAN;
 #else
-#error "Unrecognized __BYTE_ORDER"
+#error "Unrecognized __BYTE_ORDER__"
 #endif
 	enum btf_endianness swap_endian = 1 - endian;
 	struct btf *btf = NULL, *swap_btf = NULL;

tools/testing/selftests/bpf/progs/test_core_reloc_mods.c

@@ -42,7 +42,16 @@ struct core_reloc_mods {
 	core_reloc_mods_substruct_t h;
 };
 
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 #define CORE_READ(dst, src) bpf_core_read(dst, sizeof(*(dst)), src)
+#else
+#define CORE_READ(dst, src) ({ \
+	int __sz = sizeof(*(dst)) < sizeof(*(src)) ? sizeof(*(dst)) : \
+						     sizeof(*(src)); \
+	bpf_core_read((char *)(dst) + sizeof(*(dst)) - __sz, __sz, \
+		      (const char *)(src) + sizeof(*(src)) - __sz); \
+})
+#endif
 
 SEC("raw_tracepoint/sys_enter")
 int test_core_mods(void *ctx)

tools/testing/selftests/bpf/test_sysctl.c

@@ -124,7 +124,7 @@ static struct sysctl_test tests[] = {
 		.descr = "ctx:write sysctl:write read ok narrow",
 		.insns = {
 			/* u64 w = (u16)write & 1; */
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 			BPF_LDX_MEM(BPF_H, BPF_REG_7, BPF_REG_1,
 				    offsetof(struct bpf_sysctl, write)),
 #else
@@ -184,7 +184,7 @@ static struct sysctl_test tests[] = {
 		.descr = "ctx:file_pos sysctl:read read ok narrow",
 		.insns = {
 			/* If (file_pos == X) */
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 			BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_1,
 				    offsetof(struct bpf_sysctl, file_pos)),
 #else

tools/testing/selftests/bpf/verifier/ctx_skb.c

@@ -502,7 +502,7 @@
 	"check skb->hash byte load permitted",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
 		    offsetof(struct __sk_buff, hash)),
 #else
@@ -537,7 +537,7 @@
 	"check skb->hash byte load permitted 3",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
 		    offsetof(struct __sk_buff, hash) + 3),
 #else
@@ -646,7 +646,7 @@
 	"check skb->hash half load permitted",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
 		    offsetof(struct __sk_buff, hash)),
 #else
@@ -661,7 +661,7 @@
 	"check skb->hash half load permitted 2",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
 		    offsetof(struct __sk_buff, hash) + 2),
 #else
@@ -676,7 +676,7 @@
 	"check skb->hash half load not permitted, unaligned 1",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
 		    offsetof(struct __sk_buff, hash) + 1),
 #else
@@ -693,7 +693,7 @@
 	"check skb->hash half load not permitted, unaligned 3",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
 		    offsetof(struct __sk_buff, hash) + 3),
 #else
@@ -951,7 +951,7 @@
 	"check skb->data half load not permitted",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
 		    offsetof(struct __sk_buff, data)),
 #else

tools/testing/selftests/bpf/verifier/lwt.c

@@ -174,7 +174,7 @@
 	"check skb->tc_classid half load not permitted for lwt prog",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
 		    offsetof(struct __sk_buff, tc_classid)),
 #else

tools/testing/selftests/bpf/verifier/perf_event_sample_period.c

@@ -2,7 +2,7 @@
 	"check bpf_perf_event_data->sample_period byte load permitted",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
 		    offsetof(struct bpf_perf_event_data, sample_period)),
 #else
@@ -18,7 +18,7 @@
 	"check bpf_perf_event_data->sample_period half load permitted",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
 		    offsetof(struct bpf_perf_event_data, sample_period)),
 #else
@@ -34,7 +34,7 @@
 	"check bpf_perf_event_data->sample_period word load permitted",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
 		    offsetof(struct bpf_perf_event_data, sample_period)),
 #else

tools/testing/selftests/seccomp/seccomp_bpf.c

@@ -276,12 +276,12 @@ int seccomp(unsigned int op, unsigned int flags, void *args)
 }
 #endif
 
-#if __BYTE_ORDER == __LITTLE_ENDIAN
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]))
-#elif __BYTE_ORDER == __BIG_ENDIAN
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]) + sizeof(__u32))
 #else
-#error "wut? Unknown __BYTE_ORDER?!"
+#error "wut? Unknown __BYTE_ORDER__?!"
 #endif
 
 #define SIBLING_EXIT_UNKILLED	0xbadbeef