Message ID | 20240725003251.37855-3-leon.hwang@linux.dev (mailing list archive) |
---|---|
State | Superseded |
Delegated to: | BPF |
Headers | show |
Series | bpf: Fix updating attached freplace prog to PROG_ARRAY map | expand |
On 7/24/24 5:32 PM, Leon Hwang wrote: > Add a selftest to confirm the issue, which gets -EINVAL when update > attached freplace prog to PROG_ARRAY map, has been fixed. > > cd tools/testing/selftests/bpf; ./test_progs -t tailcalls > 327/25 tailcalls/tailcall_freplace:OK > 327 tailcalls:OK > Summary: 1/25 PASSED, 0 SKIPPED, 0 FAILED > > Signed-off-by: Leon Hwang <leon.hwang@linux.dev> > --- > .../selftests/bpf/prog_tests/tailcalls.c | 76 ++++++++++++++++++- > .../selftests/bpf/progs/tailcall_freplace.c | 33 ++++++++ > .../testing/selftests/bpf/progs/tc_bpf2bpf.c | 23 ++++++ > 3 files changed, 131 insertions(+), 1 deletion(-) > create mode 100644 tools/testing/selftests/bpf/progs/tailcall_freplace.c > create mode 100644 tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > > diff --git a/tools/testing/selftests/bpf/prog_tests/tailcalls.c b/tools/testing/selftests/bpf/prog_tests/tailcalls.c > index e01fabb8cc415..f1145601c0005 100644 > --- a/tools/testing/selftests/bpf/prog_tests/tailcalls.c > +++ b/tools/testing/selftests/bpf/prog_tests/tailcalls.c > @@ -5,7 +5,8 @@ > #include "tailcall_poke.skel.h" > #include "tailcall_bpf2bpf_hierarchy2.skel.h" > #include "tailcall_bpf2bpf_hierarchy3.skel.h" > - > +#include "tailcall_freplace.skel.h" > +#include "tc_bpf2bpf.skel.h" > > /* test_tailcall_1 checks basic functionality by patching multiple locations > * in a single program for a single tail call slot with nop->jmp, jmp->nop > @@ -1495,6 +1496,77 @@ static void test_tailcall_bpf2bpf_hierarchy_3(void) > RUN_TESTS(tailcall_bpf2bpf_hierarchy3); > } > > +/* test_tailcall_freplace checks that the attached freplace prog is OK to > + * update to PROG_ARRAY map. update the prog_array map. > + */ > +static void test_tailcall_freplace(void) > +{ > + struct tailcall_freplace *fr_skel = NULL; > + struct tc_bpf2bpf *tc_skel = NULL; > + struct bpf_link *fr_link = NULL; > + int prog_fd, map_fd; > + char buff[128] = {}; > + int err, key; > + > + LIBBPF_OPTS(bpf_test_run_opts, topts, > + .data_in = buff, > + .data_size_in = sizeof(buff), > + .repeat = 1, > + ); > + > + fr_skel = tailcall_freplace__open(); > + if (!ASSERT_OK_PTR(fr_skel, "open fr_skel")) if (!ASSERT_OK_PTR(fr_skel, "open fr_skel")) ==> if (!ASSERT_OK_PTR(fr_skel, "tailcall_freplace__open")) Similar for below other ASSERT_* macros. > + goto out; Let us just do 'return' here. > + > + tc_skel = tc_bpf2bpf__open_and_load(); > + if (!ASSERT_OK_PTR(tc_skel, "open tc_skel")) > + goto out; > + > + prog_fd = bpf_program__fd(tc_skel->progs.entry); > + if (!ASSERT_GE(prog_fd, 0, "tc_skel entry prog_id")) > + goto out; ASSERT_GE is not necessary, prog_fd should already be valid. > + > + err = bpf_program__set_attach_target(fr_skel->progs.entry, > + prog_fd, "subprog"); > + if (!ASSERT_OK(err, "set_attach_target")) > + goto out; > + > + err = tailcall_freplace__load(fr_skel); > + if (!ASSERT_OK(err, "load fr_skel")) > + goto out; > + > + fr_link = bpf_program__attach_freplace(fr_skel->progs.entry, > + prog_fd, "subprog"); > + if (!ASSERT_OK_PTR(fr_link, "attach_freplace")) > + goto out; > + > + prog_fd = bpf_program__fd(fr_skel->progs.entry); > + if (!ASSERT_GE(prog_fd, 0, "fr_skel entry prog_fd")) > + goto out; prog_fd is valid here. No need ASSERT_GE. > + > + map_fd = bpf_map__fd(fr_skel->maps.jmp_table); > + if (!ASSERT_GE(map_fd, 0, "fr_skel jmp_table map_fd")) > + goto out; map_fd is valid. No need ASSERT_GE. > + > + key = 0; > + err = bpf_map_update_elem(map_fd, &key, &prog_fd, BPF_ANY); > + if (!ASSERT_OK(err, "update jmp_table")) > + goto out; > + > + prog_fd = bpf_program__fd(tc_skel->progs.entry); > + if (!ASSERT_GE(prog_fd, 0, "prog_fd")) > + goto out; prog_fd is valid here. > + > + err = bpf_prog_test_run_opts(prog_fd, &topts); > + ASSERT_OK(err, "test_run"); > + ASSERT_EQ(topts.retval, 34, "test_run retval"); > + > +out: > + bpf_link__destroy(fr_link); > + tc_bpf2bpf__destroy(tc_skel); > + tailcall_freplace__destroy(fr_skel); > +} > + > void test_tailcalls(void) > { > if (test__start_subtest("tailcall_1")) > @@ -1543,4 +1615,6 @@ void test_tailcalls(void) > test_tailcall_bpf2bpf_hierarchy_fentry_entry(); > test_tailcall_bpf2bpf_hierarchy_2(); > test_tailcall_bpf2bpf_hierarchy_3(); > + if (test__start_subtest("tailcall_freplace")) > + test_tailcall_freplace(); > } > diff --git a/tools/testing/selftests/bpf/progs/tailcall_freplace.c b/tools/testing/selftests/bpf/progs/tailcall_freplace.c > new file mode 100644 > index 0000000000000..80b5fa386ed9c > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/tailcall_freplace.c > @@ -0,0 +1,33 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include <linux/bpf.h> > +#include <bpf/bpf_helpers.h> > +#include "bpf_legacy.h" bpf_legacy.h is not needed. > + > +struct { > + __uint(type, BPF_MAP_TYPE_PROG_ARRAY); > + __uint(max_entries, 1); > + __uint(key_size, sizeof(__u32)); > + __uint(value_size, sizeof(__u32)); > +} jmp_table SEC(".maps"); > + > +int count = 0; > + > +__noinline > +int subprog(struct __sk_buff *skb) > +{ > + count++; > + > + bpf_tail_call_static(skb, &jmp_table, 0); > + > + return count; > +} subprog() can be inlined into entry(). This can avoid confusing vs. tc_bpf2bpf.c. Better if you can differentiate two 'entry()' function names, e.g., entry_freplace(), entry_tc(), it can make it easy for people to understand your change in tailcalls.c. > + > +SEC("freplace") > +int entry(struct __sk_buff *skb) > +{ > + return subprog(skb); > +} > + > +char __license[] SEC("license") = "GPL"; > + > diff --git a/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > new file mode 100644 > index 0000000000000..4810961554585 > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > @@ -0,0 +1,23 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include <linux/bpf.h> > +#include <bpf/bpf_helpers.h> > +#include "bpf_legacy.h" > + > +__noinline > +int subprog(struct __sk_buff *skb) > +{ > + volatile int ret = 1; > + > + asm volatile (""::"r+"(ret)); > + return ret; > +} > + > +SEC("tc") > +int entry(struct __sk_buff *skb) > +{ > + return subprog(skb); > +} > + > +char __license[] SEC("license") = "GPL"; > +
Hi Yonghong, Thank you for your review. 26 July 2024 at 05:11, "Yonghong Song" <yonghong.song@linux.dev> wrote: > > On 7/24/24 5:32 PM, Leon Hwang wrote: > > > > > Add a selftest to confirm the issue, which gets -EINVAL when update > > > > attached freplace prog to PROG_ARRAY map, has been fixed. > > > > cd tools/testing/selftests/bpf; ./test_progs -t tailcalls > > > > 327/25 tailcalls/tailcall_freplace:OK > > > > 327 tailcalls:OK > > > > Summary: 1/25 PASSED, 0 SKIPPED, 0 FAILED > > > > Signed-off-by: Leon Hwang <leon.hwang@linux.dev> > > > > --- > > > > .../selftests/bpf/prog_tests/tailcalls.c | 76 ++++++++++++++++++- > > > > .../selftests/bpf/progs/tailcall_freplace.c | 33 ++++++++ > > > > .../testing/selftests/bpf/progs/tc_bpf2bpf.c | 23 ++++++ > > > > 3 files changed, 131 insertions(+), 1 deletion(-) > > > > create mode 100644 tools/testing/selftests/bpf/progs/tailcall_freplace.c > > > > create mode 100644 tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > > > > diff --git a/tools/testing/selftests/bpf/prog_tests/tailcalls.c b/tools/testing/selftests/bpf/prog_tests/tailcalls.c > > > > index e01fabb8cc415..f1145601c0005 100644 > > > > --- a/tools/testing/selftests/bpf/prog_tests/tailcalls.c > > > > +++ b/tools/testing/selftests/bpf/prog_tests/tailcalls.c > > > > @@ -5,7 +5,8 @@ > > > > #include "tailcall_poke.skel.h" > > > > #include "tailcall_bpf2bpf_hierarchy2.skel.h" > > > > #include "tailcall_bpf2bpf_hierarchy3.skel.h" > > > > - > > > > +#include "tailcall_freplace.skel.h" > > > > +#include "tc_bpf2bpf.skel.h" > > > > > /* test_tailcall_1 checks basic functionality by patching multiple locations > > > > * in a single program for a single tail call slot with nop->jmp, jmp->nop > > > > @@ -1495,6 +1496,77 @@ static void test_tailcall_bpf2bpf_hierarchy_3(void) > > > > RUN_TESTS(tailcall_bpf2bpf_hierarchy3); > > > > } > > > > > +/* test_tailcall_freplace checks that the attached freplace prog is OK to > > > > + * update to PROG_ARRAY map. > > > > update the prog_array map. Ack. > > > > > + */ > > > > +static void test_tailcall_freplace(void) > > > > +{ > > > > + struct tailcall_freplace *fr_skel = NULL; > > > > + struct tc_bpf2bpf *tc_skel = NULL; > > > > + struct bpf_link *fr_link = NULL; > > > > + int prog_fd, map_fd; > > > > + char buff[128] = {}; > > > > + int err, key; > > > > + > > > > + LIBBPF_OPTS(bpf_test_run_opts, topts, > > > > + .data_in = buff, > > > > + .data_size_in = sizeof(buff), > > > > + .repeat = 1, > > > > + ); > > > > + > > > > + fr_skel = tailcall_freplace__open(); > > > > + if (!ASSERT_OK_PTR(fr_skel, "open fr_skel")) > > > > if (!ASSERT_OK_PTR(fr_skel, "open fr_skel")) > > ==> > > if (!ASSERT_OK_PTR(fr_skel, "tailcall_freplace__open")) > > Similar for below other ASSERT_* macros. Ack. > > > > > + goto out; > > > > Let us just do 'return' here. Ack. > > > > > + > > > > + tc_skel = tc_bpf2bpf__open_and_load(); > > > > + if (!ASSERT_OK_PTR(tc_skel, "open tc_skel")) > > > > + goto out; > > > > + > > > > + prog_fd = bpf_program__fd(tc_skel->progs.entry); > > > > + if (!ASSERT_GE(prog_fd, 0, "tc_skel entry prog_id")) > > > > + goto out; > > > > ASSERT_GE is not necessary, prog_fd should already be valid. Ack. I should read bpf_program__fd() source code before using it. > > > > > + > > > > + err = bpf_program__set_attach_target(fr_skel->progs.entry, > > > > + prog_fd, "subprog"); > > > > + if (!ASSERT_OK(err, "set_attach_target")) > > > > + goto out; > > > > + > > > > + err = tailcall_freplace__load(fr_skel); > > > > + if (!ASSERT_OK(err, "load fr_skel")) > > > > + goto out; > > > > + > > > > + fr_link = bpf_program__attach_freplace(fr_skel->progs.entry, > > > > + prog_fd, "subprog"); > > > > + if (!ASSERT_OK_PTR(fr_link, "attach_freplace")) > > > > + goto out; > > > > + > > > > + prog_fd = bpf_program__fd(fr_skel->progs.entry); > > > > + if (!ASSERT_GE(prog_fd, 0, "fr_skel entry prog_fd")) > > > > + goto out; > > > > prog_fd is valid here. No need ASSERT_GE. Ack. > > > > > + > > > > + map_fd = bpf_map__fd(fr_skel->maps.jmp_table); > > > > + if (!ASSERT_GE(map_fd, 0, "fr_skel jmp_table map_fd")) > > > > + goto out; > > > > map_fd is valid. No need ASSERT_GE. Ack. > > > > > + > > > > + key = 0; > > > > + err = bpf_map_update_elem(map_fd, &key, &prog_fd, BPF_ANY); > > > > + if (!ASSERT_OK(err, "update jmp_table")) > > > > + goto out; > > > > + > > > > + prog_fd = bpf_program__fd(tc_skel->progs.entry); > > > > + if (!ASSERT_GE(prog_fd, 0, "prog_fd")) > > > > + goto out; > > > > prog_fd is valid here. Ack. > > > > > + > > > > + err = bpf_prog_test_run_opts(prog_fd, &topts); > > > > + ASSERT_OK(err, "test_run"); > > > > + ASSERT_EQ(topts.retval, 34, "test_run retval"); > > > > + > > > > +out: > > > > + bpf_link__destroy(fr_link); > > > > + tc_bpf2bpf__destroy(tc_skel); > > > > + tailcall_freplace__destroy(fr_skel); > > > > +} > > > > + > > > > void test_tailcalls(void) > > > > { > > > > if (test__start_subtest("tailcall_1")) > > > > @@ -1543,4 +1615,6 @@ void test_tailcalls(void) > > > > test_tailcall_bpf2bpf_hierarchy_fentry_entry(); > > > > test_tailcall_bpf2bpf_hierarchy_2(); > > > > test_tailcall_bpf2bpf_hierarchy_3(); > > > > + if (test__start_subtest("tailcall_freplace")) > > > > + test_tailcall_freplace(); > > > > } > > > > diff --git a/tools/testing/selftests/bpf/progs/tailcall_freplace.c b/tools/testing/selftests/bpf/progs/tailcall_freplace.c > > > > new file mode 100644 > > > > index 0000000000000..80b5fa386ed9c > > > > --- /dev/null > > > > +++ b/tools/testing/selftests/bpf/progs/tailcall_freplace.c > > > > @@ -0,0 +1,33 @@ > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > + > > > > +#include <linux/bpf.h> > > > > +#include <bpf/bpf_helpers.h> > > > > +#include "bpf_legacy.h" > > > > bpf_legacy.h is not needed. Ack. > > > > > + > > > > +struct { > > > > + __uint(type, BPF_MAP_TYPE_PROG_ARRAY); > > > > + __uint(max_entries, 1); > > > > + __uint(key_size, sizeof(__u32)); > > > > + __uint(value_size, sizeof(__u32)); > > > > +} jmp_table SEC(".maps"); > > > > + > > > > +int count = 0; > > > > + > > > > +__noinline > > > > +int subprog(struct __sk_buff *skb) > > > > +{ > > > > + count++; > > > > + > > > > + bpf_tail_call_static(skb, &jmp_table, 0); > > > > + > > > > + return count; > > > > +} > > > > subprog() can be inlined into entry(). This > > can avoid confusing vs. tc_bpf2bpf.c. > > Better if you can differentiate two 'entry()' function > > names, e.g., entry_freplace(), entry_tc(), it can make > > it easy for people to understand your change in tailcalls.c. Indeed. Thanks for your suggestion. > > > > > + > > > > +SEC("freplace") > > > > +int entry(struct __sk_buff *skb) > > > > +{ > > > > + return subprog(skb); > > > > +} > > > > + > > > > +char __license[] SEC("license") = "GPL"; > > > > + > > > > diff --git a/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > > > > new file mode 100644 > > > > index 0000000000000..4810961554585 > > > > --- /dev/null > > > > +++ b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > > > > @@ -0,0 +1,23 @@ > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > + > > > > +#include <linux/bpf.h> > > > > +#include <bpf/bpf_helpers.h> > > > > +#include "bpf_legacy.h" > > > > + > > > > +__noinline > > > > +int subprog(struct __sk_buff *skb) > > > > +{ > > > > + volatile int ret = 1; > > > > + > > > > + asm volatile (""::"r+"(ret)); > > > > + return ret; > > > > +} > > > > + > > > > +SEC("tc") > > > > +int entry(struct __sk_buff *skb) > > > > +{ > > > > + return subprog(skb); > > > > +} > > > > + > > > > +char __license[] SEC("license") = "GPL"; > > > > + > > >
On 7/24/24 5:32 PM, Leon Hwang wrote: > Add a selftest to confirm the issue, which gets -EINVAL when update > attached freplace prog to PROG_ARRAY map, has been fixed. > > cd tools/testing/selftests/bpf; ./test_progs -t tailcalls > 327/25 tailcalls/tailcall_freplace:OK > 327 tailcalls:OK > Summary: 1/25 PASSED, 0 SKIPPED, 0 FAILED > > Signed-off-by: Leon Hwang <leon.hwang@linux.dev> > --- > .../selftests/bpf/prog_tests/tailcalls.c | 76 ++++++++++++++++++- > .../selftests/bpf/progs/tailcall_freplace.c | 33 ++++++++ > .../testing/selftests/bpf/progs/tc_bpf2bpf.c | 23 ++++++ > 3 files changed, 131 insertions(+), 1 deletion(-) > create mode 100644 tools/testing/selftests/bpf/progs/tailcall_freplace.c > create mode 100644 tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > [...] > diff --git a/tools/testing/selftests/bpf/progs/tailcall_freplace.c b/tools/testing/selftests/bpf/progs/tailcall_freplace.c > new file mode 100644 > index 0000000000000..80b5fa386ed9c > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/tailcall_freplace.c > @@ -0,0 +1,33 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include <linux/bpf.h> > +#include <bpf/bpf_helpers.h> > +#include "bpf_legacy.h" > + > +struct { > + __uint(type, BPF_MAP_TYPE_PROG_ARRAY); > + __uint(max_entries, 1); > + __uint(key_size, sizeof(__u32)); > + __uint(value_size, sizeof(__u32)); > +} jmp_table SEC(".maps"); > + > +int count = 0; > + > +__noinline > +int subprog(struct __sk_buff *skb) > +{ > + count++; > + > + bpf_tail_call_static(skb, &jmp_table, 0); > + > + return count; > +} > + > +SEC("freplace") > +int entry(struct __sk_buff *skb) > +{ > + return subprog(skb); > +} > + > +char __license[] SEC("license") = "GPL"; > + extra line in the above. > diff --git a/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > new file mode 100644 > index 0000000000000..4810961554585 > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > @@ -0,0 +1,23 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include <linux/bpf.h> > +#include <bpf/bpf_helpers.h> > +#include "bpf_legacy.h" > + > +__noinline > +int subprog(struct __sk_buff *skb) > +{ > + volatile int ret = 1; > + > + asm volatile (""::"r+"(ret)); > + return ret; > +} > + > +SEC("tc") > +int entry(struct __sk_buff *skb) > +{ > + return subprog(skb); > +} > + > +char __license[] SEC("license") = "GPL"; > + extra line in the above.
26 July 2024 at 14:16, "Yonghong Song" <yonghong.song@linux.dev> wrote: > > On 7/24/24 5:32 PM, Leon Hwang wrote: > > > > > Add a selftest to confirm the issue, which gets -EINVAL when update > > > > attached freplace prog to PROG_ARRAY map, has been fixed. > > > > cd tools/testing/selftests/bpf; ./test_progs -t tailcalls > > > > 327/25 tailcalls/tailcall_freplace:OK > > > > 327 tailcalls:OK > > > > Summary: 1/25 PASSED, 0 SKIPPED, 0 FAILED > > > > Signed-off-by: Leon Hwang <leon.hwang@linux.dev> > > > > --- > > > > .../selftests/bpf/prog_tests/tailcalls.c | 76 ++++++++++++++++++- > > > > .../selftests/bpf/progs/tailcall_freplace.c | 33 ++++++++ > > > > .../testing/selftests/bpf/progs/tc_bpf2bpf.c | 23 ++++++ > > > > 3 files changed, 131 insertions(+), 1 deletion(-) > > > > create mode 100644 tools/testing/selftests/bpf/progs/tailcall_freplace.c > > > > create mode 100644 tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > > > > [...] > > > > > diff --git a/tools/testing/selftests/bpf/progs/tailcall_freplace.c b/tools/testing/selftests/bpf/progs/tailcall_freplace.c > > > > new file mode 100644 > > > > index 0000000000000..80b5fa386ed9c > > > > --- /dev/null > > > > +++ b/tools/testing/selftests/bpf/progs/tailcall_freplace.c > > > > @@ -0,0 +1,33 @@ > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > + > > > > +#include <linux/bpf.h> > > > > +#include <bpf/bpf_helpers.h> > > > > +#include "bpf_legacy.h" > > > > + > > > > +struct { > > > > + __uint(type, BPF_MAP_TYPE_PROG_ARRAY); > > > > + __uint(max_entries, 1); > > > > + __uint(key_size, sizeof(__u32)); > > > > + __uint(value_size, sizeof(__u32)); > > > > +} jmp_table SEC(".maps"); > > > > + > > > > +int count = 0; > > > > + > > > > +__noinline > > > > +int subprog(struct __sk_buff *skb) > > > > +{ > > > > + count++; > > > > + > > > > + bpf_tail_call_static(skb, &jmp_table, 0); > > > > + > > > > + return count; > > > > +} > > > > + > > > > +SEC("freplace") > > > > +int entry(struct __sk_buff *skb) > > > > +{ > > > > + return subprog(skb); > > > > +} > > > > + > > > > +char __license[] SEC("license") = "GPL"; > > > > + > > > > extra line in the above. Ack. > > > > > diff --git a/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > > > > new file mode 100644 > > > > index 0000000000000..4810961554585 > > > > --- /dev/null > > > > +++ b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c > > > > @@ -0,0 +1,23 @@ > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > + > > > > +#include <linux/bpf.h> > > > > +#include <bpf/bpf_helpers.h> > > > > +#include "bpf_legacy.h" > > > > + > > > > +__noinline > > > > +int subprog(struct __sk_buff *skb) > > > > +{ > > > > + volatile int ret = 1; > > > > + > > > > + asm volatile (""::"r+"(ret)); > > > > + return ret; > > > > +} > > > > + > > > > +SEC("tc") > > > > +int entry(struct __sk_buff *skb) > > > > +{ > > > > + return subprog(skb); > > > > +} > > > > + > > > > +char __license[] SEC("license") = "GPL"; > > > > + > > > > extra line in the above. > Ack. Thanks, Leon
diff --git a/tools/testing/selftests/bpf/prog_tests/tailcalls.c b/tools/testing/selftests/bpf/prog_tests/tailcalls.c index e01fabb8cc415..f1145601c0005 100644 --- a/tools/testing/selftests/bpf/prog_tests/tailcalls.c +++ b/tools/testing/selftests/bpf/prog_tests/tailcalls.c @@ -5,7 +5,8 @@ #include "tailcall_poke.skel.h" #include "tailcall_bpf2bpf_hierarchy2.skel.h" #include "tailcall_bpf2bpf_hierarchy3.skel.h" - +#include "tailcall_freplace.skel.h" +#include "tc_bpf2bpf.skel.h" /* test_tailcall_1 checks basic functionality by patching multiple locations * in a single program for a single tail call slot with nop->jmp, jmp->nop @@ -1495,6 +1496,77 @@ static void test_tailcall_bpf2bpf_hierarchy_3(void) RUN_TESTS(tailcall_bpf2bpf_hierarchy3); } +/* test_tailcall_freplace checks that the attached freplace prog is OK to + * update to PROG_ARRAY map. + */ +static void test_tailcall_freplace(void) +{ + struct tailcall_freplace *fr_skel = NULL; + struct tc_bpf2bpf *tc_skel = NULL; + struct bpf_link *fr_link = NULL; + int prog_fd, map_fd; + char buff[128] = {}; + int err, key; + + LIBBPF_OPTS(bpf_test_run_opts, topts, + .data_in = buff, + .data_size_in = sizeof(buff), + .repeat = 1, + ); + + fr_skel = tailcall_freplace__open(); + if (!ASSERT_OK_PTR(fr_skel, "open fr_skel")) + goto out; + + tc_skel = tc_bpf2bpf__open_and_load(); + if (!ASSERT_OK_PTR(tc_skel, "open tc_skel")) + goto out; + + prog_fd = bpf_program__fd(tc_skel->progs.entry); + if (!ASSERT_GE(prog_fd, 0, "tc_skel entry prog_id")) + goto out; + + err = bpf_program__set_attach_target(fr_skel->progs.entry, + prog_fd, "subprog"); + if (!ASSERT_OK(err, "set_attach_target")) + goto out; + + err = tailcall_freplace__load(fr_skel); + if (!ASSERT_OK(err, "load fr_skel")) + goto out; + + fr_link = bpf_program__attach_freplace(fr_skel->progs.entry, + prog_fd, "subprog"); + if (!ASSERT_OK_PTR(fr_link, "attach_freplace")) + goto out; + + prog_fd = bpf_program__fd(fr_skel->progs.entry); + if (!ASSERT_GE(prog_fd, 0, "fr_skel entry prog_fd")) + goto out; + + map_fd = bpf_map__fd(fr_skel->maps.jmp_table); + if (!ASSERT_GE(map_fd, 0, "fr_skel jmp_table map_fd")) + goto out; + + key = 0; + err = bpf_map_update_elem(map_fd, &key, &prog_fd, BPF_ANY); + if (!ASSERT_OK(err, "update jmp_table")) + goto out; + + prog_fd = bpf_program__fd(tc_skel->progs.entry); + if (!ASSERT_GE(prog_fd, 0, "prog_fd")) + goto out; + + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "test_run"); + ASSERT_EQ(topts.retval, 34, "test_run retval"); + +out: + bpf_link__destroy(fr_link); + tc_bpf2bpf__destroy(tc_skel); + tailcall_freplace__destroy(fr_skel); +} + void test_tailcalls(void) { if (test__start_subtest("tailcall_1")) @@ -1543,4 +1615,6 @@ void test_tailcalls(void) test_tailcall_bpf2bpf_hierarchy_fentry_entry(); test_tailcall_bpf2bpf_hierarchy_2(); test_tailcall_bpf2bpf_hierarchy_3(); + if (test__start_subtest("tailcall_freplace")) + test_tailcall_freplace(); } diff --git a/tools/testing/selftests/bpf/progs/tailcall_freplace.c b/tools/testing/selftests/bpf/progs/tailcall_freplace.c new file mode 100644 index 0000000000000..80b5fa386ed9c --- /dev/null +++ b/tools/testing/selftests/bpf/progs/tailcall_freplace.c @@ -0,0 +1,33 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include "bpf_legacy.h" + +struct { + __uint(type, BPF_MAP_TYPE_PROG_ARRAY); + __uint(max_entries, 1); + __uint(key_size, sizeof(__u32)); + __uint(value_size, sizeof(__u32)); +} jmp_table SEC(".maps"); + +int count = 0; + +__noinline +int subprog(struct __sk_buff *skb) +{ + count++; + + bpf_tail_call_static(skb, &jmp_table, 0); + + return count; +} + +SEC("freplace") +int entry(struct __sk_buff *skb) +{ + return subprog(skb); +} + +char __license[] SEC("license") = "GPL"; + diff --git a/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c new file mode 100644 index 0000000000000..4810961554585 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include "bpf_legacy.h" + +__noinline +int subprog(struct __sk_buff *skb) +{ + volatile int ret = 1; + + asm volatile (""::"r+"(ret)); + return ret; +} + +SEC("tc") +int entry(struct __sk_buff *skb) +{ + return subprog(skb); +} + +char __license[] SEC("license") = "GPL"; +
Add a selftest to confirm the issue, which gets -EINVAL when update attached freplace prog to PROG_ARRAY map, has been fixed. cd tools/testing/selftests/bpf; ./test_progs -t tailcalls 327/25 tailcalls/tailcall_freplace:OK 327 tailcalls:OK Summary: 1/25 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Leon Hwang <leon.hwang@linux.dev> --- .../selftests/bpf/prog_tests/tailcalls.c | 76 ++++++++++++++++++- .../selftests/bpf/progs/tailcall_freplace.c | 33 ++++++++ .../testing/selftests/bpf/progs/tc_bpf2bpf.c | 23 ++++++ 3 files changed, 131 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/progs/tailcall_freplace.c create mode 100644 tools/testing/selftests/bpf/progs/tc_bpf2bpf.c