From 98b0bf02738004829d7e26d6cb47b2e469aaba86 Mon Sep 17 00:00:00 2001 From: Yang Weijiang Date: Fri, 14 Aug 2020 21:21:05 +0800 Subject: selftests: kvm: Use a shorter encoding to clear RAX If debug_regs.c is built with newer binutils, the resulting binary is "optimized" by the assembler: asm volatile("ss_start: " "xor %%rax,%%rax\n\t" "cpuid\n\t" "movl $0x1a0,%%ecx\n\t" "rdmsr\n\t" : : : "rax", "ecx"); is translated to : 000000000040194e : 40194e: 31 c0 xor %eax,%eax <----- rax->eax? 401950: 0f a2 cpuid 401952: b9 a0 01 00 00 mov $0x1a0,%ecx 401957: 0f 32 rdmsr As you can see rax is replaced with eax in target binary code. This causes a difference is the length of xor instruction (2 Byte vs 3 Byte), and makes the hard-coded instruction length check fail: /* Instruction lengths starting at ss_start */ int ss_size[4] = { 3, /* xor */ <-------- 2 or 3? 2, /* cpuid */ 5, /* mov */ 2, /* rdmsr */ }; Encode the shorter version directly and, while at it, fix the "clobbers" of the asm. Cc: stable@vger.kernel.org Signed-off-by: Yang Weijiang Signed-off-by: Paolo Bonzini --- tools/testing/selftests/kvm/x86_64/debug_regs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/kvm/x86_64/debug_regs.c b/tools/testing/selftests/kvm/x86_64/debug_regs.c index 8162c58a1234..b8d14f9db5f9 100644 --- a/tools/testing/selftests/kvm/x86_64/debug_regs.c +++ b/tools/testing/selftests/kvm/x86_64/debug_regs.c @@ -40,11 +40,11 @@ static void guest_code(void) /* Single step test, covers 2 basic instructions and 2 emulated */ asm volatile("ss_start: " - "xor %%rax,%%rax\n\t" + "xor %%eax,%%eax\n\t" "cpuid\n\t" "movl $0x1a0,%%ecx\n\t" "rdmsr\n\t" - : : : "rax", "ecx"); + : : : "eax", "ebx", "ecx", "edx"); /* DR6.BD test */ asm volatile("bd_start: mov %%dr0, %%rax" : : : "rax"); -- cgit v1.2.3-59-g8ed1b From 3fb1a96a91120877488071a167d26d76be4be977 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Tue, 18 Aug 2020 09:44:56 -0700 Subject: libbpf: Fix build on ppc64le architecture MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On ppc64le we get the following warning: In file included from btf_dump.c:16:0: btf_dump.c: In function ‘btf_dump_emit_struct_def’: ../include/linux/kernel.h:20:17: error: comparison of distinct pointer types lacks a cast [-Werror] (void) (&_max1 == &_max2); \ ^ btf_dump.c:882:11: note: in expansion of macro ‘max’ m_sz = max(0LL, btf__resolve_size(d->btf, m->type)); ^~~ Fix by explicitly casting to __s64, which is a return type from btf__resolve_size(). Fixes: 702eddc77a90 ("libbpf: Handle GCC built-in types for Arm NEON") Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200818164456.1181661-1-andriin@fb.com --- tools/lib/bpf/btf_dump.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c index fe39bd774697..57c00fa63932 100644 --- a/tools/lib/bpf/btf_dump.c +++ b/tools/lib/bpf/btf_dump.c @@ -879,7 +879,7 @@ static void btf_dump_emit_struct_def(struct btf_dump *d, btf_dump_printf(d, ": %d", m_sz); off = m_off + m_sz; } else { - m_sz = max(0LL, btf__resolve_size(d->btf, m->type)); + m_sz = max((__s64)0, btf__resolve_size(d->btf, m->type)); off = m_off + m_sz * 8; } btf_dump_printf(d, ";"); -- cgit v1.2.3-59-g8ed1b From 00fa1d83a8b50351c830521d00135e823c46e7d0 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Tue, 18 Aug 2020 15:23:12 -0700 Subject: bpftool: Handle EAGAIN error code properly in pids collection When the error code is EAGAIN, the kernel signals the user space should retry the read() operation for bpf iterators. Let us do it. Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200818222312.2181675-1-yhs@fb.com --- tools/bpf/bpftool/pids.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'tools') diff --git a/tools/bpf/bpftool/pids.c b/tools/bpf/bpftool/pids.c index e3b116325403..df7d8ec76036 100644 --- a/tools/bpf/bpftool/pids.c +++ b/tools/bpf/bpftool/pids.c @@ -134,6 +134,8 @@ int build_obj_refs_table(struct obj_refs_table *table, enum bpf_obj_type type) while (true) { ret = read(fd, buf, sizeof(buf)); if (ret < 0) { + if (errno == EAGAIN) + continue; err = -errno; p_err("failed to read PID iterator output: %d", err); goto out; -- cgit v1.2.3-59-g8ed1b From 1e891e513e16c145cc9b45b1fdb8bf4a4f2f9557 Mon Sep 17 00:00:00 2001 From: Toke Høiland-Jørgensen Date: Wed, 19 Aug 2020 13:05:34 +0200 Subject: libbpf: Fix map index used in error message MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The error message emitted by bpf_object__init_user_btf_maps() was using the wrong section ID. Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20200819110534.9058-1-toke@redhat.com --- tools/lib/bpf/libbpf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 5d20b2da4427..0ad0b0491e1f 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -2264,7 +2264,7 @@ static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict, data = elf_getdata(scn, NULL); if (!scn || !data) { pr_warn("failed to get Elf_Data from map section %d (%s)\n", - obj->efile.maps_shndx, MAPS_ELF_SEC); + obj->efile.btf_maps_shndx, MAPS_ELF_SEC); return -EINVAL; } -- cgit v1.2.3-59-g8ed1b From 51f6463aacfbfd322bcaadc606da56acef644b05 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 19 Aug 2020 11:23:42 +0200 Subject: tools/resolve_btfids: Fix sections with wrong alignment The data of compressed section should be aligned to 4 (for 32bit) or 8 (for 64 bit) bytes. The binutils ld sets sh_addralign to 1, which makes libelf fail with misaligned section error during the update as reported by Jesper: FAILED elf_update(WRITE): invalid section alignment While waiting for ld fix, we can fix compressed sections sh_addralign value manually. Adding warning in -vv mode when the fix is triggered: $ ./tools/bpf/resolve_btfids/resolve_btfids -vv vmlinux ... section(36) .comment, size 44, link 0, flags 30, type=1 section(37) .debug_aranges, size 45684, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 16, expected 8 section(38) .debug_info, size 129104957, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 1, expected 8 section(39) .debug_abbrev, size 1152583, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 1, expected 8 section(40) .debug_line, size 7374522, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 1, expected 8 section(41) .debug_frame, size 702463, link 0, flags 800, type=1 section(42) .debug_str, size 1017571, link 0, flags 830, type=1 - fixing wrong alignment sh_addralign 1, expected 8 section(43) .debug_loc, size 3019453, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 1, expected 8 section(44) .debug_ranges, size 1744583, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 16, expected 8 section(45) .symtab, size 2955888, link 46, flags 0, type=2 section(46) .strtab, size 2613072, link 0, flags 0, type=3 ... update ok for vmlinux Another workaround is to disable compressed debug info data CONFIG_DEBUG_INFO_COMPRESSED kernel option. Fixes: fbbb68de80a4 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object") Reported-by: Jesper Dangaard Brouer Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Acked-by: Jesper Dangaard Brouer Acked-by: Yonghong Song Cc: Mark Wielaard Cc: Nick Clifton Link: https://lore.kernel.org/bpf/20200819092342.259004-1-jolsa@kernel.org --- tools/bpf/resolve_btfids/main.c | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) (limited to 'tools') diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c index 4d9ecb975862..0def0bb1f783 100644 --- a/tools/bpf/resolve_btfids/main.c +++ b/tools/bpf/resolve_btfids/main.c @@ -233,6 +233,39 @@ static struct btf_id *add_symbol(struct rb_root *root, char *name, size_t size) return btf_id__add(root, id, false); } +/* + * The data of compressed section should be aligned to 4 + * (for 32bit) or 8 (for 64 bit) bytes. The binutils ld + * sets sh_addralign to 1, which makes libelf fail with + * misaligned section error during the update: + * FAILED elf_update(WRITE): invalid section alignment + * + * While waiting for ld fix, we fix the compressed sections + * sh_addralign value manualy. + */ +static int compressed_section_fix(Elf *elf, Elf_Scn *scn, GElf_Shdr *sh) +{ + int expected = gelf_getclass(elf) == ELFCLASS32 ? 4 : 8; + + if (!(sh->sh_flags & SHF_COMPRESSED)) + return 0; + + if (sh->sh_addralign == expected) + return 0; + + pr_debug2(" - fixing wrong alignment sh_addralign %u, expected %u\n", + sh->sh_addralign, expected); + + sh->sh_addralign = expected; + + if (gelf_update_shdr(scn, sh) == 0) { + printf("FAILED cannot update section header: %s\n", + elf_errmsg(-1)); + return -1; + } + return 0; +} + static int elf_collect(struct object *obj) { Elf_Scn *scn = NULL; @@ -309,6 +342,9 @@ static int elf_collect(struct object *obj) obj->efile.idlist_shndx = idx; obj->efile.idlist_addr = sh.sh_addr; } + + if (compressed_section_fix(elf, scn, &sh)) + return -1; } return 0; -- cgit v1.2.3-59-g8ed1b From 5597432dde62befd3ab92e6ef9e073564e277ea8 Mon Sep 17 00:00:00 2001 From: Veronika Kabatova Date: Wed, 19 Aug 2020 18:07:10 +0200 Subject: selftests/bpf: Remove test_align leftovers Calling generic selftests "make install" fails as rsync expects all files from TEST_GEN_PROGS to be present. The binary is not generated anymore (commit 3b09d27cc93d) so we can safely remove it from there and also from gitignore. Fixes: 3b09d27cc93d ("selftests/bpf: Move test_align under test_progs") Signed-off-by: Veronika Kabatova Signed-off-by: Alexei Starovoitov Acked-by: Jesper Dangaard Brouer Link: https://lore.kernel.org/bpf/20200819160710.1345956-1-vkabatov@redhat.com --- tools/testing/selftests/bpf/.gitignore | 1 - tools/testing/selftests/bpf/Makefile | 2 +- 2 files changed, 1 insertion(+), 2 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore index 1bb204cee853..9a0946ddb705 100644 --- a/tools/testing/selftests/bpf/.gitignore +++ b/tools/testing/selftests/bpf/.gitignore @@ -6,7 +6,6 @@ test_lpm_map test_tag FEATURE-DUMP.libbpf fixdep -test_align test_dev_cgroup /test_progs* test_tcpbpf_user diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index a83b5827532f..fc946b7ac288 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -32,7 +32,7 @@ LDLIBS += -lcap -lelf -lz -lrt -lpthread # Order correspond to 'make run_tests' order TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \ - test_align test_verifier_log test_dev_cgroup test_tcpbpf_user \ + test_verifier_log test_dev_cgroup test_tcpbpf_user \ test_sock test_btf test_sockmap get_cgroup_id_user test_socket_cookie \ test_cgroup_storage \ test_netcnt test_tcpnotify_user test_sock_fields test_sysctl \ -- cgit v1.2.3-59-g8ed1b From c210773d6c6f595f5922d56b7391fe343bc7310e Mon Sep 17 00:00:00 2001 From: Yauheni Kaliuta Date: Thu, 20 Aug 2020 14:58:43 +0300 Subject: bpf: selftests: global_funcs: Check err_str before strstr The error path in libbpf.c:load_program() has calls to pr_warn() which ends up for global_funcs tests to test_global_funcs.c:libbpf_debug_print(). For the tests with no struct test_def::err_str initialized with a string, it causes call of strstr() with NULL as the second argument and it segfaults. Fix it by calling strstr() only for non-NULL err_str. Signed-off-by: Yauheni Kaliuta Signed-off-by: Alexei Starovoitov Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20200820115843.39454-1-yauheni.kaliuta@redhat.com --- tools/testing/selftests/bpf/prog_tests/test_global_funcs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c b/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c index 25b068591e9a..193002b14d7f 100644 --- a/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c +++ b/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c @@ -19,7 +19,7 @@ static int libbpf_debug_print(enum libbpf_print_level level, log_buf = va_arg(args, char *); if (!log_buf) goto out; - if (strstr(log_buf, err_str) == 0) + if (err_str && strstr(log_buf, err_str) == 0) found = true; out: printf(format, log_buf); -- cgit v1.2.3-59-g8ed1b From b16fc097bc283184cde40e5b30d15705e1590410 Mon Sep 17 00:00:00 2001 From: Tobias Klauser Date: Fri, 21 Aug 2020 15:36:42 +0200 Subject: bpf: Fix two typos in uapi/linux/bpf.h Also remove trailing whitespaces in bpf_skb_get_tunnel_key example code. Signed-off-by: Tobias Klauser Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200821133642.18870-1-tklauser@distanz.ch --- include/uapi/linux/bpf.h | 10 +++++----- tools/include/uapi/linux/bpf.h | 10 +++++----- 2 files changed, 10 insertions(+), 10 deletions(-) (limited to 'tools') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 0480f893facd..b6238b2209b7 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -767,7 +767,7 @@ union bpf_attr { * * Also, note that **bpf_trace_printk**\ () is slow, and should * only be used for debugging purposes. For this reason, a notice - * bloc (spanning several lines) is printed to kernel logs and + * block (spanning several lines) is printed to kernel logs and * states that the helper should not be used "for production use" * the first time this helper is used (or more precisely, when * **trace_printk**\ () buffers are allocated). For passing values @@ -1033,14 +1033,14 @@ union bpf_attr { * * int ret; * struct bpf_tunnel_key key = {}; - * + * * ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0); * if (ret < 0) * return TC_ACT_SHOT; // drop packet - * + * * if (key.remote_ipv4 != 0x0a000001) * return TC_ACT_SHOT; // drop packet - * + * * return TC_ACT_OK; // accept packet * * This interface can also be used with all encapsulation devices @@ -1147,7 +1147,7 @@ union bpf_attr { * Description * Retrieve the realm or the route, that is to say the * **tclassid** field of the destination for the *skb*. The - * indentifier retrieved is a user-provided tag, similar to the + * identifier retrieved is a user-provided tag, similar to the * one used with the net_cls cgroup (see description for * **bpf_get_cgroup_classid**\ () helper), but here this tag is * held by a route (a destination entry), not by a task. diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 0480f893facd..b6238b2209b7 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -767,7 +767,7 @@ union bpf_attr { * * Also, note that **bpf_trace_printk**\ () is slow, and should * only be used for debugging purposes. For this reason, a notice - * bloc (spanning several lines) is printed to kernel logs and + * block (spanning several lines) is printed to kernel logs and * states that the helper should not be used "for production use" * the first time this helper is used (or more precisely, when * **trace_printk**\ () buffers are allocated). For passing values @@ -1033,14 +1033,14 @@ union bpf_attr { * * int ret; * struct bpf_tunnel_key key = {}; - * + * * ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0); * if (ret < 0) * return TC_ACT_SHOT; // drop packet - * + * * if (key.remote_ipv4 != 0x0a000001) * return TC_ACT_SHOT; // drop packet - * + * * return TC_ACT_OK; // accept packet * * This interface can also be used with all encapsulation devices @@ -1147,7 +1147,7 @@ union bpf_attr { * Description * Retrieve the realm or the route, that is to say the * **tclassid** field of the destination for the *skb*. The - * indentifier retrieved is a user-provided tag, similar to the + * identifier retrieved is a user-provided tag, similar to the * one used with the net_cls cgroup (see description for * **bpf_get_cgroup_classid**\ () helper), but here this tag is * held by a route (a destination entry), not by a task. -- cgit v1.2.3-59-g8ed1b