Improve the receive_pkt() function to enable it to receive packets from
multiple sockets. Define a sock_num variable to iterate through all the
sockets in the Rx path. Add nb_valid_entries to check that all the
expected number of packets are received.
Revise the function __receive_pkts() to only inspect the receive ring
once, handle any received packets, and promptly return. Implement a bitmap
to store the value of number of sockets. Update Makefile to include
find_bit.c for compiling xskxceiver.
Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-5-tushar.vyavahare@intel.com
Adding selftest that puts kprobe on bpf_fentry_test1 that calls bpf_printk
and invokes bpf_trace_printk tracepoint. The bpf_trace_printk tracepoint
has test[234] programs attached to it.
Because kprobe execution goes through bpf_prog_active check, programs
attached to the tracepoint will fail the recursion check and increment the
recursion_misses stats.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-10-jolsa@kernel.org
Adding selftest that puts kprobe.multi on bpf_fentry_test1 that
calls bpf_kfunc_common_test kfunc which has 3 perf event kprobes
and 1 kprobe.multi attached.
Because fprobe (kprobe.multi attach layear) does not have strict
recursion check the kprobe's bpf_prog_active check is hit for test2-5.
Disabling this test for arm64, because there's no fprobe support yet.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-9-jolsa@kernel.org
This exercises the newly added dynsym symbol versioning logics.
Now we accept symbols in form of func, func@LIB_VERSION or
func@@LIB_VERSION.
The test rely on liburandom_read.so. For liburandom_read.so, we have:
$ nm -D liburandom_read.so
w __cxa_finalize@GLIBC_2.17
w __gmon_start__
w _ITM_deregisterTMCloneTable
w _ITM_registerTMCloneTable
0000000000000000 A LIBURANDOM_READ_1.0.0
0000000000000000 A LIBURANDOM_READ_2.0.0
000000000000081c T urandlib_api@@LIBURANDOM_READ_2.0.0
0000000000000814 T urandlib_api@LIBURANDOM_READ_1.0.0
0000000000000824 T urandlib_api_sameoffset@LIBURANDOM_READ_1.0.0
0000000000000824 T urandlib_api_sameoffset@@LIBURANDOM_READ_2.0.0
000000000000082c T urandlib_read_without_sema@@LIBURANDOM_READ_1.0.0
00000000000007c4 T urandlib_read_with_sema@@LIBURANDOM_READ_1.0.0
0000000000011018 D urandlib_read_with_sema_semaphore@@LIBURANDOM_READ_1.0.0
For `urandlib_api`, specifying `urandlib_api` will cause a conflict because
there are two symbols named urandlib_api and both are global bind.
For `urandlib_api_sameoffset`, there are also two symbols in the .so, but
both are at the same offset and essentially they refer to the same function
so no conflict.
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230918024813.237475-4-hengqi.chen@gmail.com
test_progs -t bind_perm,bpf_obj_pinning/mounted-str-rel fails when
the selftests directory is mounted under /mnt, which is a reasonable
thing to do when sharing the selftests residing on the host with a
virtual machine, e.g., using 9p.
The reason is that cgroup2 is mounted at /mnt and not unmounted,
causing subsequent tests that need to access the selftests directory
to fail.
Fix by unmounting it. The kernel maintains a mount stack, so this
reveals what was mounted there before. Introduce cgroup_workdir_mounted
in order to maintain idempotency. Make it thread-local in order to
support test_progs -j.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230919101336.2223655-3-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Alexei reported seeing log messages for some test cases even though we
just wanted to match the error string from the verifier. Move the
printing of the log buffer to a guarded condition so that we only print
it when we fail to match on the expected string in the log buffer,
preventing unneeded output when running the test.
Reported-by: Alexei Starovoitov <ast@kernel.org>
Fixes: d2a93715bf ("selftests/bpf: Add tests for BPF exceptions")
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230918155233.297024-2-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add macros implementing an 'assert' statement primitive using macros,
built on top of the BPF exceptions support introduced in previous
patches.
The bpf_assert_*_with variants allow supplying a value which can the be
inspected within the exception handler to signify the assert statement
that led to the program being terminated abruptly, or be returned by the
default exception handler.
Note that only 64-bit scalar values are supported with these assertion
macros, as during testing I found other cases quite unreliable in
presence of compiler shifts/manipulations extracting the value of the
right width from registers scrubbing the verifier's bounds information
and knowledge about the value in the register.
Thus, it is easier to reliably support this feature with only the full
register width, and support both signed and unsigned variants.
The bpf_assert_range is interesting in particular, which clamps the
value in the [begin, end] (both inclusive) range within verifier state,
and emits a check for the same at runtime.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230912233214.1518551-17-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
By default, the subprog generated by the verifier to handle a thrown
exception hardcodes a return value of 0. To allow user-defined logic
and modification of the return value when an exception is thrown,
introduce the 'exception_callback:' declaration tag, which marks a
callback as the default exception handler for the program.
The format of the declaration tag is 'exception_callback:<value>', where
<value> is the name of the exception callback. Each main program can be
tagged using this BTF declaratiion tag to associate it with an exception
callback. In case the tag is absent, the default callback is used.
As such, the exception callback cannot be modified at runtime, only set
during verification.
Allowing modification of the callback for the current program execution
at runtime leads to issues when the programs begin to nest, as any
per-CPU state maintaing this information will have to be saved and
restored. We don't want it to stay in bpf_prog_aux as this takes a
global effect for all programs. An alternative solution is spilling
the callback pointer at a known location on the program stack on entry,
and then passing this location to bpf_throw as a parameter.
However, since exceptions are geared more towards a use case where they
are ideally never invoked, optimizing for this use case and adding to
the complexity has diminishing returns.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230912233214.1518551-7-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch implements BPF exceptions, and introduces a bpf_throw kfunc
to allow programs to throw exceptions during their execution at runtime.
A bpf_throw invocation is treated as an immediate termination of the
program, returning back to its caller within the kernel, unwinding all
stack frames.
This allows the program to simplify its implementation, by testing for
runtime conditions which the verifier has no visibility into, and assert
that they are true. In case they are not, the program can simply throw
an exception from the other branch.
BPF exceptions are explicitly *NOT* an unlikely slowpath error handling
primitive, and this objective has guided design choices of the
implementation of the them within the kernel (with the bulk of the cost
for unwinding the stack offloaded to the bpf_throw kfunc).
The implementation of this mechanism requires use of add_hidden_subprog
mechanism introduced in the previous patch, which generates a couple of
instructions to move R1 to R0 and exit. The JIT then rewrites the
prologue of this subprog to take the stack pointer and frame pointer as
inputs and reset the stack frame, popping all callee-saved registers
saved by the main subprog. The bpf_throw function then walks the stack
at runtime, and invokes this exception subprog with the stack and frame
pointers as parameters.
Reviewers must take note that currently the main program is made to save
all callee-saved registers on x86_64 during entry into the program. This
is because we must do an equivalent of a lightweight context switch when
unwinding the stack, therefore we need the callee-saved registers of the
caller of the BPF program to be able to return with a sane state.
Note that we have to additionally handle r12, even though it is not used
by the program, because when throwing the exception the program makes an
entry into the kernel which could clobber r12 after saving it on the
stack. To be able to preserve the value we received on program entry, we
push r12 and restore it from the generated subprogram when unwinding the
stack.
For now, bpf_throw invocation fails when lingering resources or locks
exist in that path of the program. In a future followup, bpf_throw will
be extended to perform frame-by-frame unwinding to release lingering
resources for each stack frame, removing this limitation.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230912233214.1518551-5-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
In a number of places at en error, exit_with_error() is called that
terminates the whole test suite. This is not always desirable as it
would be more logical to only fail that test and then go along with
the other ones. So change this in a number of places in which I
thought it would be more logical to just fail the test in
question. Examples of this are in code that is only used by a single
test.
Also delete a pointless if-statement in receive_pkts() that has an
exit_with_error() in it. It can never occur since the return value is
an unsigned and the test is for less than zero.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/r/20230914084900.492-10-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a command line option to be able to run a single test. This option
(-t) takes a number from the list of tests available with the "-l"
option. Here are two examples:
Run test number 2, the "receive single packet" test in all available modes:
./test_xsk.sh -t 2
Run test number 21, the metadata copy test in skb mode only
./test_xsh.sh -t 21 -m skb
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/r/20230914084900.492-8-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a command line option (-l) that lists all the tests. The number
before the test will be used in the next commit for specifying a
single test to run. Here is an example of the output:
Tests:
0: SEND_RECEIVE
1: SEND_RECEIVE_2K_FRAME
2: SEND_RECEIVE_SINGLE_PKT
3: POLL_RX
4: POLL_TX
5: POLL_RXQ_FULL
6: POLL_TXQ_FULL
7: SEND_RECEIVE_UNALIGNED
:
:
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/r/20230914084900.492-7-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Declare the test names statically in a struct so that we can refer to
them when adding the support to execute a single test in the next
commit. Before this patch, the names of them were not declared in a
single place which made it not possible to refer to them.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/r/20230914084900.492-6-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Prepare for the capability to be able to run a single test by moving
all the tests to their own functions. This function can then be called
to execute that test in the next commit.
Also, the tests named RUN_TO_COMPLETION_* were not named well, so
change them to SEND_RECEIVE_* as it is just a basic send and receive
test of 4K packets.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/r/20230914084900.492-5-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a timeout for the transmission thread. If packets are not
completed properly, for some reason, the test harness would previously
get stuck forever in a while loop. But with this patch, this timeout
will trigger, flag the test as a failure, and continue with the next
test.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/r/20230914084900.492-3-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Print info about every packet in verbose mode, both for Tx and
Rx. This is useful to have when a test fails or to validate that a
test is really doing what it was designed to do. Info on what is
supposed to be received and sent is also printed for the custom packet
streams since they differ from the base line. Here is an example:
Tx addr: 37e0 len: 64 options: 0 pkt_nb: 8
Tx addr: 4000 len: 64 options: 0 pkt_nb: 9
Rx: addr: 100 len: 64 options: 0 pkt_nb: 0 valid: 1
Rx: addr: 1100 len: 64 options: 0 pkt_nb: 1 valid: 1
Rx: addr: 2100 len: 64 options: 0 pkt_nb: 4 valid: 1
Rx: addr: 3100 len: 64 options: 0 pkt_nb: 8 valid: 1
Rx: addr: 4100 len: 64 options: 0 pkt_nb: 9 valid: 1
One pointless verbose print statement is also deleted and another one
is made clearer.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/r/20230914084900.492-2-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Commit 1d56ade032 changed the function get_unpriv_disabled() to
return its results as a bool instead of updating a global variable, but
test_verifier was not updated to keep in line with these changes. Thus
unpriv_disabled is always false in test_verifier and unprivileged tests
are not properly skipped on systems with unprivileged bpf disabled.
Fixes: 1d56ade032 ("selftests/bpf: Unprivileged tests for test_loader.c")
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230912120631.213139-1-asavkov@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add 4 test cases to confirm the tailcall infinite loop bug has been fixed.
Like tailcall_bpf2bpf cases, do fentry/fexit on the bpf2bpf, and then
check the final count result.
tools/testing/selftests/bpf/test_progs -t tailcalls
226/13 tailcalls/tailcall_bpf2bpf_fentry:OK
226/14 tailcalls/tailcall_bpf2bpf_fexit:OK
226/15 tailcalls/tailcall_bpf2bpf_fentry_fexit:OK
226/16 tailcalls/tailcall_bpf2bpf_fentry_entry:OK
226 tailcalls:OK
Summary: 1/16 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Leon Hwang <hffilwlqm@gmail.com>
Link: https://lore.kernel.org/r/20230912150442.2009-4-hffilwlqm@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
