[ Upstream commit 9676feccac ]
The prototype of .features is netdev_features_t, it should use
NETIF_F_LLTX and NETIF_F_HW_VLAN_STAG_TX, not NETIF_F_LLTX_BIT
and NETIF_F_HW_VLAN_STAG_TX_BIT.
Fixes: cf204a7183 ("bpf, testing: Introduce 'gso_linear_no_head_frag' skb_segment test")
Signed-off-by: Jian Shen <shenjian15@huawei.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20220622135002.8263-1-shenjian15@huawei.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 18935a72eb ]
This patch fixes an error in the tail call limit test that caused the
test to fail on for x86-64 JIT. Previously, the register R0 was used to
report the total number of tail calls made. However, after a tail call
fall-through, the value of the R0 register is undefined. Now, all tail
call error path tests instead use context state to store the count.
Fixes: 874be05f52 ("bpf, tests: Add tail call test suite")
Reported-by: Paul Chaignon <paul@cilium.io>
Reported-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Link: https://lore.kernel.org/bpf/20210914091842.4186267-14-johan.almbladh@anyfinetworks.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Turn BPF_PROG_RUN into a proper always inlined function. No functional and
performance changes are intended, but it makes it much easier to understand
what's going on with how BPF programs are actually get executed. It's more
obvious what types and callbacks are expected. Also extra () around input
parameters can be dropped, as well as `__` variable prefixes intended to avoid
naming collisions, which makes the code simpler to read and write.
This refactoring also highlighted one extra issue. BPF_PROG_RUN is both
a macro and an enum value (BPF_PROG_RUN == BPF_PROG_TEST_RUN). Turning
BPF_PROG_RUN into a function causes naming conflict compilation error. So
rename BPF_PROG_RUN into lower-case bpf_prog_run(), similar to
bpf_prog_run_xdp(), bpf_prog_run_pin_on_cpu(), etc. All existing callers of
BPF_PROG_RUN, the macro, are switched to bpf_prog_run() explicitly.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210815070609.987780-2-andrii@kernel.org
While BPF_CALL instructions were tested implicitly by the cBPF-to-eBPF
translation, there has not been any tests for BPF_TAIL_CALL instructions.
The new test suite includes tests for tail call chaining, tail call count
tracking and error paths. It is mainly intended for JIT development and
testing.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210809091829.810076-15-johan.almbladh@anyfinetworks.com
Tests for BPF_CMPXCHG with both word and double word operands. As with
the tests for other atomic operations, these tests only check the result
of the arithmetic operation. The atomicity of the operations is not tested.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210809091829.810076-14-johan.almbladh@anyfinetworks.com
Tests for each atomic arithmetic operation and BPF_XCHG, derived from
old BPF_XADD tests. The tests include BPF_W/DW and BPF_FETCH variants.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210809091829.810076-13-johan.almbladh@anyfinetworks.com
Some JITs may need to convert a conditional jump instruction to
to short PC-relative branch and a long unconditional jump, if the
PC-relative offset exceeds offset field width in the CPU instruction.
This test triggers such branch conversion on the 32-bit MIPS JIT.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210809091829.810076-11-johan.almbladh@anyfinetworks.com
A double word (64-bit) load/store may be implemented as two successive
32-bit operations, one for each word. Check that the order of those
operations is consistent with the machine endianness.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210809091829.810076-10-johan.almbladh@anyfinetworks.com
32-bit JITs may implement complex ALU64 instructions using function calls.
The new tests check aspects related to this, such as register clobbering
and register argument re-ordering.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210809091829.810076-9-johan.almbladh@anyfinetworks.com
This patch adds BPF_MUL tests for 64x32 and 64x64 multiply. Mainly
testing 32-bit JITs that implement ALU64 operations with two 32-bit
CPU registers per operand.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210809091829.810076-8-johan.almbladh@anyfinetworks.com
This patch adds a number of tests for BPF_LSH, BPF_RSH amd BPF_ARSH
ALU64 operations with values that may trigger different JIT code paths.
Mainly testing 32-bit JITs that implement ALU64 operations with two
32-bit CPU registers per operand.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210809091829.810076-7-johan.almbladh@anyfinetworks.com
This patch adds more tests of ALU32 shift operations BPF_LSH and BPF_RSH,
including the special case of a zero immediate. Also add corresponding
BPF_ARSH tests which were missing for ALU32.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210809091829.810076-6-johan.almbladh@anyfinetworks.com
This patch adds tests of BPF_AND, BPF_OR and BPF_XOR with different
magnitude of the immediate value. Mainly checking 32-bit JIT sub-word
handling and zero/sign extension.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210809091829.810076-5-johan.almbladh@anyfinetworks.com
This patch corrects the test description in a number of cases where
the description differed from what was actually tested and expected.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210809091829.810076-4-johan.almbladh@anyfinetworks.com
Tests for ALU32 and ALU64 MOV with different sizes of the immediate
value. Depending on the immediate field width of the native CPU
instructions, a JIT may generate code differently depending on the
immediate value. Test that zero or sign extension is performed as
expected. Mainly for JIT testing.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210809091829.810076-3-johan.almbladh@anyfinetworks.com
An eBPF JIT may implement JMP32 operations in a different way than JMP,
especially on 32-bit architectures. This patch adds a series of tests
for JMP32 operations, mainly for testing JITs.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210809091829.810076-2-johan.almbladh@anyfinetworks.com
Each test case can have a set of sub-tests, where each sub-test can
run the cBPF/eBPF test snippet with its own data_size and expected
result. Before, the end of the sub-test array was indicated by both
data_size and result being zero. However, most or all of the internal
eBPF tests has a data_size of zero already. When such a test also had
an expected value of zero, the test was never run but reported as
PASS anyway.
Now the test runner always runs the first sub-test, regardless of the
data_size and result values. The sub-test array zero-termination only
applies for any additional sub-tests.
There are other ways fix it of course, but this solution at least
removes the surprise of eBPF tests with a zero result always succeeding.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210721103822.3755111-1-johan.almbladh@anyfinetworks.com
A subsequent patch will add additional atomic operations. These new
operations will use the same opcode field as the existing XADD, with
the immediate discriminating different operations.
In preparation, rename the instruction mode BPF_ATOMIC and start
calling the zero immediate BPF_ADD.
This is possible (doesn't break existing valid BPF progs) because the
immediate field is currently reserved MBZ and BPF_ADD is zero.
All uses are removed from the tree but the BPF_XADD definition is
kept around to avoid breaking builds for people including kernel
headers.
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Björn Töpel <bjorn.topel@gmail.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-5-jackmanb@google.com
This reverts commit 3203c90100 ("test_bpf: flag tests that cannot
be jited on s390").
The s390 bpf JIT previously had a restriction on the maximum program
size, which required some tests in test_bpf to be flagged as expected
failures. The program size limitation has been removed, and the tests
now pass, so these tests should no longer be flagged.
Fixes: d1242b10ff ("s390/bpf: Remove JITed image size limitations")
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/20200716143931.330122-1-seth.forshee@canonical.com
Replace the preemption disable/enable with migrate_disable/enable() to
reflect the actual requirement and to allow PREEMPT_RT to substitute it
with an actual migration disable mechanism which does not disable
preemption.
[ tglx: Switched it over to migrate disable ]
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.785306549@linutronix.de
Following reports of skb_segment() hitting a BUG_ON when working on
GROed skbs which have their gso_size mangled (e.g. after a
bpf_skb_change_proto call), add a reproducer test that mimics the
input skbs that lead to the mentioned BUG_ON as in [1] and validates the
fix submitted in [2].
[1] https://lists.openwall.net/netdev/2019/08/26/110
[2] commit 3dcbdb134f ("net: gso: Fix skb_segment splat when splitting gso_size mangled skb having linear-headed frag_list")
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191025134223.2761-3-shmulik.ladkani@gmail.com
Currently, test_skb_segment() builds a single test skb and runs
skb_segment() on it.
Extend test_skb_segment() so it processes an array of numerous
skb/feature pairs to test.
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191025134223.2761-2-shmulik.ladkani@gmail.com
r369217 in clang added a new warning about potential misuse of the xor
operator as an exponentiation operator:
../lib/test_bpf.c:870:13: warning: result of '10 ^ 300' is 294; did you
mean '1e300'? [-Wxor-used-as-pow]
{ { 4, 10 ^ 300 }, { 20, 10 ^ 300 } },
~~~^~~~~
1e300
../lib/test_bpf.c:870:13: note: replace expression with '0xA ^ 300' to
silence this warning
../lib/test_bpf.c:870:31: warning: result of '10 ^ 300' is 294; did you
mean '1e300'? [-Wxor-used-as-pow]
{ { 4, 10 ^ 300 }, { 20, 10 ^ 300 } },
~~~^~~~~
1e300
../lib/test_bpf.c:870:31: note: replace expression with '0xA ^ 300' to
silence this warning
The commit link for this new warning has some good logic behind wanting
to add it but this instance appears to be a false positive. Adopt its
suggestion to silence the warning but not change the code. According to
the differential review link in the clang commit, GCC may eventually
adopt this warning as well.
Link: https://github.com/ClangBuiltLinux/linux/issues/643
Link: 920890e268
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of version 2 of the gnu general public license as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 64 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.894819585@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace VLAN_TAG_PRESENT with single bit flag and free up
VLAN.CFI overload. Now VLAN.CFI is visible in networking stack
and can be passed around intact.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
Flag with FLAG_EXPECTED_FAIL the BPF_MAXINSNS tests that cannot be jited
on s390 because they exceed BPF_SIZE_MAX and fail when
CONFIG_BPF_JIT_ALWAYS_ON is set. Also set .expected_errcode to -ENOTSUPP
so the tests pass in that case.
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
We have one triggering on eBPF but lets also add a cBPF example to
make sure we keep tracking them. Also add anther cBPF test running
max number of MSH ops.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Remove all eBPF tests involving LD_ABS/LD_IND from test_bpf.ko. Reason
is that the eBPF tests from test_bpf module do not go via BPF verifier
and therefore any instruction rewrites from verifier cannot take place.
Therefore, move them into test_verifier which runs out of user space,
so that verfier can rewrite LD_ABS/LD_IND internally in upcoming patches.
It will have the same effect since runtime tests are also performed from
there. This also allows to finally unexport bpf_skb_vlan_{push,pop}_proto
and keep it internal to core kernel.
Additionally, also add further cBPF LD_ABS/LD_IND test coverage into
test_bpf.ko suite.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The skb_segment() function returns error pointers on error. It never
returns NULL.
Fixes: 76db8087c4 ("net: bpf: add a test for skb_segment in test_bpf module")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Yonghong Song <yhs@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Without the previous commit,
"modprobe test_bpf" will have the following errors:
...
[ 98.149165] ------------[ cut here ]------------
[ 98.159362] kernel BUG at net/core/skbuff.c:3667!
[ 98.169756] invalid opcode: 0000 [#1] SMP PTI
[ 98.179370] Modules linked in:
[ 98.179371] test_bpf(+)
...
which triggers the bug the previous commit intends to fix.
The skbs are constructed to mimic what mlx5 may generate.
The packet size/header may not mimic real cases in production. But
the processing flow is similar.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Function bpf_fill_maxinsns11 is designed to not be able to be JITed on
x86_64. So, it fails when CONFIG_BPF_JIT_ALWAYS_ON=y, and
commit 09584b4067 ("bpf: fix selftests/bpf test_kmod.sh failure when
CONFIG_BPF_JIT_ALWAYS_ON=y") makes sure that failure is detected on that
case.
However, it does not fail on other architectures, which have a different
JIT compiler design. So, test_bpf has started to fail to load on those.
After this fix, test_bpf loads fine on both x86_64 and ppc64el.
Fixes: 09584b4067 ("bpf: fix selftests/bpf test_kmod.sh failure when CONFIG_BPF_JIT_ALWAYS_ON=y")
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
For tests that are using the maximal number of BPF instruction, each
run takes 20 usec. Looping 10,000 times on them totals 200 ms, which
is bad when the loop is not preemptible.
test_bpf: #264 BPF_MAXINSNS: Call heavy transformations jited:1 19248
18548 PASS
test_bpf: #269 BPF_MAXINSNS: ld_abs+get_processor_id jited:1 20896 PASS
Lets divide by ten the number of iterations, so that max latency is
20ms. We could use need_resched() to break the loop earlier if we
believe 20 ms is too much.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
test_bpf() is taking 1.6 seconds nowadays, it is time
to add a schedule point in it.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Update selftests to relfect recent changes and add various new
test cases.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a couple of test cases for interpreter and JIT that are
related to an issue we faced some time ago in Cilium [1],
which is fixed in LLVM with commit e53750e1e086 ("bpf: fix
bug on silently truncating 64-bit immediate").
Test cases were run-time checking kernel to behave as intended
which should also provide some guidance for current or new
JITs in case they should trip over this. Added for cBPF and
eBPF.
[1] https://github.com/cilium/cilium/pull/2162
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The BPF interpreter has been used as part of the spectre 2 attack CVE-2017-5715.
A quote from goolge project zero blog:
"At this point, it would normally be necessary to locate gadgets in
the host kernel code that can be used to actually leak data by reading
from an attacker-controlled location, shifting and masking the result
appropriately and then using the result of that as offset to an
attacker-controlled address for a load. But piecing gadgets together
and figuring out which ones work in a speculation context seems annoying.
So instead, we decided to use the eBPF interpreter, which is built into
the host kernel - while there is no legitimate way to invoke it from inside
a VM, the presence of the code in the host kernel's text section is sufficient
to make it usable for the attack, just like with ordinary ROP gadgets."
To make attacker job harder introduce BPF_JIT_ALWAYS_ON config
option that removes interpreter from the kernel in favor of JIT-only mode.
So far eBPF JIT is supported by:
x64, arm64, arm32, sparc64, s390, powerpc64, mips64
The start of JITed program is randomized and code page is marked as read-only.
In addition "constant blinding" can be turned on with net.core.bpf_jit_harden
v2->v3:
- move __bpf_prog_ret0 under ifdef (Daniel)
v1->v2:
- fix init order, test_bpf and cBPF (Daniel's feedback)
- fix offloaded bpf (Jakub's feedback)
- add 'return 0' dummy in case something can invoke prog->bpf_func
- retarget bpf tree. For bpf-next the patch would need one extra hunk.
It will be sent when the trees are merged back to net-next
Considered doing:
int bpf_jit_enable __read_mostly = BPF_EBPF_JIT_DEFAULT;
but it seems better to land the patch as-is and in bpf-next remove
bpf_jit_enable global variable from all JITs, consolidate in one place
and remove this jit_init() function.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add a test that i) uses LD_ABS, ii) zeroing R6 before call, iii) calls
a helper that triggers reload of cached skb data, iv) uses LD_ABS again.
It's added for test_bpf in order to do runtime testing after JITing as
well as test_verifier to test that the sequence is allowed.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Currently, eBPF only understands BPF_JGT (>), BPF_JGE (>=),
BPF_JSGT (s>), BPF_JSGE (s>=) instructions, this means that
particularly *JLT/*JLE counterparts involving immediates need
to be rewritten from e.g. X < [IMM] by swapping arguments into
[IMM] > X, meaning the immediate first is required to be loaded
into a register Y := [IMM], such that then we can compare with
Y > X. Note that the destination operand is always required to
be a register.
This has the downside of having unnecessarily increased register
pressure, meaning complex program would need to spill other
registers temporarily to stack in order to obtain an unused
register for the [IMM]. Loading to registers will thus also
affect state pruning since we need to account for that register
use and potentially those registers that had to be spilled/filled
again. As a consequence slightly more stack space might have
been used due to spilling, and BPF programs are a bit longer
due to extra code involving the register load and potentially
required spill/fills.
Thus, add BPF_JLT (<), BPF_JLE (<=), BPF_JSLT (s<), BPF_JSLE (s<=)
counterparts to the eBPF instruction set. Modifying LLVM to
remove the NegateCC() workaround in a PoC patch at [1] and
allowing it to also emit the new instructions resulted in
cilium's BPF programs that are injected into the fast-path to
have a reduced program length in the range of 2-3% (e.g.
accumulated main and tail call sections from one of the object
file reduced from 4864 to 4729 insns), reduced complexity in
the range of 10-30% (e.g. accumulated sections reduced in one
of the cases from 116432 to 88428 insns), and reduced stack
usage in the range of 1-5% (e.g. accumulated sections from one
of the object files reduced from 824 to 784b).
The modification for LLVM will be incorporated in a backwards
compatible way. Plan is for LLVM to have i) a target specific
option to offer a possibility to explicitly enable the extension
by the user (as we have with -m target specific extensions today
for various CPU insns), and ii) have the kernel checked for
presence of the extensions and enable them transparently when
the user is selecting more aggressive options such as -march=native
in a bpf target context. (Other frontends generating BPF byte
code, e.g. ply can probe the kernel directly for its code
generation.)
[1] https://github.com/borkmann/llvm/tree/bpf-insns
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
On MIPS, conditional branches can only span 32k instructions. To
exceed this limit in the JIT with the BPF maximum of 4k insns, we need
to choose eBPF insns that expand to more than 8 machine instructions.
Use BPF_LD_ABS as it is quite complex. This forces the JIT to invert
the sense of the branch to branch around a long jump to the end.
This (somewhat) verifies that the branch inversion logic and target
address calculation of the long jumps are done correctly.
Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
test_bpf.ko doesn't call verifier before selecting interpreter or JITing,
hence the tests need to manually specify the amount of stack they consume.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some JITs can optimize comparisons with zero. Add a couple of
BPF_JSGE tests against immediate zero.
Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>