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Fix bug in handling bpf_testmod unloading that will cause test_progs exiting
prematurely if bpf_testmod unloading failed. This is especially problematic
when running a subset of test_progs that doesn't require root permissions and
doesn't rely on bpf_testmod, yet will fail immediately due to exit(1) in
unload_bpf_testmod().
Fixes: 9f7fa225894c ("selftests/bpf: Add bpf_testmod kernel module for testing")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210126065019.1268027-1-andrii@kernel.org
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There exists many build warnings when make M=samples/bpf on the Loongson
platform, this issue is MIPS related, x86 compiles just fine.
Here are some warnings:
CC samples/bpf/ibumad_user.o
samples/bpf/ibumad_user.c: In function ‘dump_counts’:
samples/bpf/ibumad_user.c:46:24: warning: format ‘%llu’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
printf("0x%02x : %llu\n", key, value);
~~~^ ~~~~~
%lu
CC samples/bpf/offwaketime_user.o
samples/bpf/offwaketime_user.c: In function ‘print_ksym’:
samples/bpf/offwaketime_user.c:34:17: warning: format ‘%llx’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
printf("%s/%llx;", sym->name, addr);
~~~^ ~~~~
%lx
samples/bpf/offwaketime_user.c: In function ‘print_stack’:
samples/bpf/offwaketime_user.c:68:17: warning: format ‘%lld’ expects argument of type ‘long long int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
printf(";%s %lld\n", key->waker, count);
~~~^ ~~~~~
%ld
MIPS needs __SANE_USERSPACE_TYPES__ before <linux/types.h> to select
'int-ll64.h' in arch/mips/include/uapi/asm/types.h, then it can avoid
build warnings when printing __u64 with %llu, %llx or %lld.
The header tools/include/linux/types.h defines __SANE_USERSPACE_TYPES__,
it seems that we can include <linux/types.h> in the source files which
have build warnings, but it has no effect due to actually it includes
usr/include/linux/types.h instead of tools/include/linux/types.h, the
problem is that "usr/include" is preferred first than "tools/include"
in samples/bpf/Makefile, that sounds like a ugly hack to -Itools/include
before -Iusr/include.
So define __SANE_USERSPACE_TYPES__ for MIPS in samples/bpf/Makefile
is proper, if add "TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__" in
samples/bpf/Makefile, it appears the following error:
Auto-detecting system features:
... libelf: [ on ]
... zlib: [ on ]
... bpf: [ OFF ]
BPF API too old
make[3]: *** [Makefile:293: bpfdep] Error 1
make[2]: *** [Makefile:156: all] Error 2
With #ifndef __SANE_USERSPACE_TYPES__ in tools/include/linux/types.h,
the above error has gone and this ifndef change does not hurt other
compilations.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/1611551146-14052-1-git-send-email-yangtiezhu@loongson.cn
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Update struct bpf_perf_event_data with the addr field to match the
tools headers with the kernel headers.
Signed-off-by: Florian Lehner <dev@der-flo.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210123185221.23946-1-dev@der-flo.net
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There is no need to cast to void * when the argument is void *. Avoid
cluttering of code.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-13-bjorn.topel@gmail.com
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Use calloc instead of malloc where it makes sense, and avoid C++-style
void *-cast.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-12-bjorn.topel@gmail.com
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The data variable is only used locally. Instead of using the heap,
stick to using the stack.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-11-bjorn.topel@gmail.com
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Use C89 rules for variable definition.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-10-bjorn.topel@gmail.com
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Instead of casting from void *, let us use the actual type in
gen_udp_hdr().
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-9-bjorn.topel@gmail.com
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Instead of casting from void *, let us use the actual type in
init_iface_config().
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-8-bjorn.topel@gmail.com
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Let us use a local variable in nsswitchthread(), so we can remove a
lot of casting for better readability.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-7-bjorn.topel@gmail.com
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Introduce a local variable to get rid of lot of casting. Move common
code outside the if/else-clause.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-6-bjorn.topel@gmail.com
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The allocated entry is immediately overwritten by an assignment. Fix
that.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-5-bjorn.topel@gmail.com
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Silence three checkpatch style warnings.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-4-bjorn.topel@gmail.com
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The enums undef and bidi are not used. Remove them.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-3-bjorn.topel@gmail.com
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Instead of passing void * all over the place, let us pass the actual
type (ifobject) and remove the void-ptr-to-type-ptr casting.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-2-bjorn.topel@gmail.com
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Add detection for kernel version, and adapt the BPF program based on
kernel support. This way, users will get the best possible performance
from the BPF program.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Marek Majtyka <alardam@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210122105351.11751-4-bjorn.topel@gmail.com
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Change 'exeeds' to 'exceeds'.
Signed-off-by: Junlin Yang <yangjunlin@yulong.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210121122309.1501-1-angkery@163.com
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For very large ELF objects (with many sections), we could
get special value SHN_XINDEX (65535) for elf object's string
table index - e_shstrndx.
Call elf_getshdrstrndx to get the proper string table index,
instead of reading it directly from ELF header.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210121202203.9346-4-jolsa@kernel.org
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Add custom implementation of getsockopt hook for TCP_ZEROCOPY_RECEIVE.
We skip generic hooks for TCP_ZEROCOPY_RECEIVE and have a custom
call in do_tcp_getsockopt using the on-stack data. This removes
3% overhead for locking/unlocking the socket.
Without this patch:
3.38% 0.07% tcp_mmap [kernel.kallsyms] [k] __cgroup_bpf_run_filter_getsockopt
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--3.30%--__cgroup_bpf_run_filter_getsockopt
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--0.81%--__kmalloc
With the patch applied:
0.52% 0.12% tcp_mmap [kernel.kallsyms] [k] __cgroup_bpf_run_filter_getsockopt_kern
Note, exporting uapi/tcp.h requires removing netinet/tcp.h
from test_progs.h because those headers have confliciting
definitions.
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210115163501.805133-2-sdf@google.com
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llvm patch https://reviews.llvm.org/D84002 permitted
to emit empty rodata datasec if the elf .rodata section
contains read-only data from local variables. These
local variables will be not emitted as BTF_KIND_VARs
since llvm converted these local variables as
static variables with private linkage without debuginfo
types. Such an empty rodata datasec will make
skeleton code generation easy since for skeleton
a rodata struct will be generated if there is a
.rodata elf section. The existence of a rodata
btf datasec is also consistent with the existence
of a rodata map created by libbpf.
The btf with such an empty rodata datasec will fail
in the kernel though as kernel will reject a datasec
with zero vlen and zero size. For example, for the below code,
int sys_enter(void *ctx)
{
int fmt[6] = {1, 2, 3, 4, 5, 6};
int dst[6];
bpf_probe_read(dst, sizeof(dst), fmt);
return 0;
}
We got the below btf (bpftool btf dump ./test.o):
[1] PTR '(anon)' type_id=0
[2] FUNC_PROTO '(anon)' ret_type_id=3 vlen=1
'ctx' type_id=1
[3] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED
[4] FUNC 'sys_enter' type_id=2 linkage=global
[5] INT 'char' size=1 bits_offset=0 nr_bits=8 encoding=SIGNED
[6] ARRAY '(anon)' type_id=5 index_type_id=7 nr_elems=4
[7] INT '__ARRAY_SIZE_TYPE__' size=4 bits_offset=0 nr_bits=32 encoding=(none)
[8] VAR '_license' type_id=6, linkage=global-alloc
[9] DATASEC '.rodata' size=0 vlen=0
[10] DATASEC 'license' size=0 vlen=1
type_id=8 offset=0 size=4
When loading the ./test.o to the kernel with bpftool,
we see the following error:
libbpf: Error loading BTF: Invalid argument(22)
libbpf: magic: 0xeb9f
...
[6] ARRAY (anon) type_id=5 index_type_id=7 nr_elems=4
[7] INT __ARRAY_SIZE_TYPE__ size=4 bits_offset=0 nr_bits=32 encoding=(none)
[8] VAR _license type_id=6 linkage=1
[9] DATASEC .rodata size=24 vlen=0 vlen == 0
libbpf: Error loading .BTF into kernel: -22. BTF is optional, ignoring.
Basically, libbpf changed .rodata datasec size to 24 since elf .rodata
section size is 24. The kernel then rejected the BTF since vlen = 0.
Note that the above kernel verifier failure can be worked around with
changing local variable "fmt" to a static or global, optionally const, variable.
This patch permits a datasec with vlen = 0 in kernel.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210119153519.3901963-1-yhs@fb.com
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Reuse module_attach infrastructure to add a new bare tracepoint to check
we can attach to it as a raw tracepoint.
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210119122237.2426878-3-qais.yousef@arm.com
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There are 3 tests added into verifier's jit tests to trigger x64
jit jump padding.
The first test can be represented as the following assembly code:
1: bpf_call bpf_get_prandom_u32
2: if r0 == 1 goto pc+128
3: if r0 == 2 goto pc+128
...
129: if r0 == 128 goto pc+128
130: goto pc+128
131: goto pc+127
...
256: goto pc+2
257: goto pc+1
258: r0 = 1
259: ret
We first store a random number to r0 and add the corresponding
conditional jumps (2~129) to make verifier believe that those jump
instructions from 130 to 257 are reachable. When the program is sent to
x64 jit, it starts to optimize out the NOP jumps backwards from 257.
Since there are 128 such jumps, the program easily reaches 15 passes and
triggers jump padding.
Here is the x64 jit code of the first test:
0: 0f 1f 44 00 00 nop DWORD PTR [rax+rax*1+0x0]
5: 66 90 xchg ax,ax
7: 55 push rbp
8: 48 89 e5 mov rbp,rsp
b: e8 4c 90 75 e3 call 0xffffffffe375905c
10: 48 83 f8 01 cmp rax,0x1
14: 0f 84 fe 04 00 00 je 0x518
1a: 48 83 f8 02 cmp rax,0x2
1e: 0f 84 f9 04 00 00 je 0x51d
...
f6: 48 83 f8 18 cmp rax,0x18
fa: 0f 84 8b 04 00 00 je 0x58b
100: 48 83 f8 19 cmp rax,0x19
104: 0f 84 86 04 00 00 je 0x590
10a: 48 83 f8 1a cmp rax,0x1a
10e: 0f 84 81 04 00 00 je 0x595
...
500: 0f 84 83 01 00 00 je 0x689
506: 48 81 f8 80 00 00 00 cmp rax,0x80
50d: 0f 84 76 01 00 00 je 0x689
513: e9 71 01 00 00 jmp 0x689
518: e9 6c 01 00 00 jmp 0x689
...
5fe: e9 86 00 00 00 jmp 0x689
603: e9 81 00 00 00 jmp 0x689
608: 0f 1f 00 nop DWORD PTR [rax]
60b: eb 7c jmp 0x689
60d: eb 7a jmp 0x689
...
683: eb 04 jmp 0x689
685: eb 02 jmp 0x689
687: 66 90 xchg ax,ax
689: b8 01 00 00 00 mov eax,0x1
68e: c9 leave
68f: c3 ret
As expected, a 3 bytes NOPs is inserted at 608 due to the transition
from imm32 jmp to imm8 jmp. A 2 bytes NOPs is also inserted at 687 to
replace a NOP jump.
The second test case is tricky. Here is the assembly code:
1: bpf_call bpf_get_prandom_u32
2: if r0 == 1 goto pc+2048
3: if r0 == 2 goto pc+2048
...
2049: if r0 == 2048 goto pc+2048
2050: goto pc+2048
2051: goto pc+16
2052: goto pc+15
...
2064: goto pc+3
2065: goto pc+2
2066: goto pc+1
...
[repeat "goto pc+16".."goto pc+1" 127 times]
...
4099: r0 = 2
4100: ret
There are 4 major parts of the program.
1) 1~2049: Those are instructions to make 2050~4098 reachable. Some of
them also could generate the padding for jmp_cond.
2) 2050: This is the target instruction for the imm32 nop jmp padding.
3) 2051~4098: The repeated "goto 1~16" instructions are designed to be
consumed by the nop jmp optimization. In the end, those
instrucitons become 128 continuous 0 offset jmp and are
optimized out in 1 pass, and this make insn 2050 an imm32
nop jmp in the next pass, so that we can trigger the
5 bytes padding.
4) 4099~4100: Those are the instructions to end the program.
The x64 jit code is like this:
0: 0f 1f 44 00 00 nop DWORD PTR [rax+rax*1+0x0]
5: 66 90 xchg ax,ax
7: 55 push rbp
8: 48 89 e5 mov rbp,rsp
b: e8 bc 7b d5 d3 call 0xffffffffd3d57bcc
10: 48 83 f8 01 cmp rax,0x1
14: 0f 84 7e 66 00 00 je 0x6698
1a: 48 83 f8 02 cmp rax,0x2
1e: 0f 84 74 66 00 00 je 0x6698
24: 48 83 f8 03 cmp rax,0x3
28: 0f 84 6a 66 00 00 je 0x6698
2e: 48 83 f8 04 cmp rax,0x4
32: 0f 84 60 66 00 00 je 0x6698
38: 48 83 f8 05 cmp rax,0x5
3c: 0f 84 56 66 00 00 je 0x6698
42: 48 83 f8 06 cmp rax,0x6
46: 0f 84 4c 66 00 00 je 0x6698
...
666c: 48 81 f8 fe 07 00 00 cmp rax,0x7fe
6673: 0f 1f 40 00 nop DWORD PTR [rax+0x0]
6677: 74 1f je 0x6698
6679: 48 81 f8 ff 07 00 00 cmp rax,0x7ff
6680: 0f 1f 40 00 nop DWORD PTR [rax+0x0]
6684: 74 12 je 0x6698
6686: 48 81 f8 00 08 00 00 cmp rax,0x800
668d: 0f 1f 40 00 nop DWORD PTR [rax+0x0]
6691: 74 05 je 0x6698
6693: 0f 1f 44 00 00 nop DWORD PTR [rax+rax*1+0x0]
6698: b8 02 00 00 00 mov eax,0x2
669d: c9 leave
669e: c3 ret
Since insn 2051~4098 are optimized out right before the padding pass,
there are several conditional jumps from the first part are replaced with
imm8 jmp_cond, and this triggers the 4 bytes padding, for example at
6673, 6680, and 668d. On the other hand, Insn 2050 is replaced with the
5 bytes nops at 6693.
The third test is to invoke the first and second tests as subprogs to test
bpf2bpf. Per the system log, there was one more jit happened with only
one pass and the same jit code was produced.
v4:
- Add the second test case which triggers jmp_cond padding and imm32 nop
jmp padding.
- Add the new test case as another subprog
Signed-off-by: Gary Lin <glin@suse.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210119102501.511-4-glin@suse.com
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Currently tests for bpf_get_ns_current_pid_tgid() are outside test_progs.
This change folds test cases into test_progs.
Changes from v11:
- Fixed test failure is not detected.
- Removed EXIT(3) call as it will stop test_progs execution.
Signed-off-by: Carlos Neira <cneirabustos@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210114141033.GA17348@localhost
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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Conflicts:
drivers/net/can/dev.c
commit 03f16c5075b2 ("can: dev: can_restart: fix use after free bug")
commit 3e77f70e7345 ("can: dev: move driver related infrastructure into separate subdir")
Code move.
drivers/net/dsa/b53/b53_common.c
commit 8e4052c32d6b ("net: dsa: b53: fix an off by one in checking "vlan->vid"")
commit b7a9e0da2d1c ("net: switchdev: remove vid_begin -> vid_end range from VLAN objects")
Field rename.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Networking fixes for 5.11-rc5, including fixes from bpf, wireless, and
can trees.
Current release - regressions:
- nfc: nci: fix the wrong NCI_CORE_INIT parameters
Current release - new code bugs:
- bpf: allow empty module BTFs
Previous releases - regressions:
- bpf: fix signed_{sub,add32}_overflows type handling
- tcp: do not mess with cloned skbs in tcp_add_backlog()
- bpf: prevent double bpf_prog_put call from bpf_tracing_prog_attach
- bpf: don't leak memory in bpf getsockopt when optlen == 0
- tcp: fix potential use-after-free due to double kfree()
- mac80211: fix encryption issues with WEP
- devlink: use right genl user_ptr when handling port param get/set
- ipv6: set multicast flag on the multicast route
- tcp: fix TCP_USER_TIMEOUT with zero window
Previous releases - always broken:
- bpf: local storage helpers should check nullness of owner ptr passed
- mac80211: fix incorrect strlen of .write in debugfs
- cls_flower: call nla_ok() before nla_next()
- skbuff: back tiny skbs with kmalloc() in __netdev_alloc_skb() too"
* tag 'net-5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (52 commits)
net: systemport: free dev before on error path
net: usb: cdc_ncm: don't spew notifications
net: mscc: ocelot: Fix multicast to the CPU port
tcp: Fix potential use-after-free due to double kfree()
bpf: Fix signed_{sub,add32}_overflows type handling
can: peak_usb: fix use after free bugs
can: vxcan: vxcan_xmit: fix use after free bug
can: dev: can_restart: fix use after free bug
tcp: fix TCP socket rehash stats mis-accounting
net: dsa: b53: fix an off by one in checking "vlan->vid"
tcp: do not mess with cloned skbs in tcp_add_backlog()
selftests: net: fib_tests: remove duplicate log test
net: nfc: nci: fix the wrong NCI_CORE_INIT parameters
sh_eth: Fix power down vs. is_opened flag ordering
net: Disable NETIF_F_HW_TLS_RX when RXCSUM is disabled
netfilter: rpfilter: mask ecn bits before fib lookup
udp: mask TOS bits in udp_v4_early_demux()
xsk: Clear pool even for inactive queues
bpf: Fix helper bpf_map_peek_elem_proto pointing to wrong callback
sh_eth: Make PHY access aware of Runtime PM to fix reboot crash
...
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There are two spelling mistakes in check_fail messages. Fix them.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20210118111902.71096-1-colin.king@canonical.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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The previous test added an address with a specified metric and check if
correspond route was created. I somehow added two logs for the same
test. Remove the duplicated one.
Reported-by: Antoine Tenart <atenart@redhat.com>
Fixes: 0d29169a708b ("selftests/net/fib_tests: update addr_metric_test for peer route testing")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20210119025930.2810532-1-liuhangbin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix 'CPU too large' error in Intel PT
- Correct event attribute sizes in 'perf inject'
- Sync build_bug.h and kvm.h kernel copies
- Fix bpf.h header include directive in 5sec.c 'perf trace' bpf example
- libbpf tests fixes
- Fix shadow stat 'perf test' for non-bash shells
- Take cgroups into account for shadow stats in 'perf stat'
* tag 'perf-tools-fixes-2021-01-17' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf inject: Correct event attribute sizes
perf intel-pt: Fix 'CPU too large' error
perf stat: Take cgroups into account for shadow stats
perf stat: Introduce struct runtime_stat_data
libperf tests: Fail when failing to get a tracepoint id
libperf tests: If a test fails return non-zero
libperf tests: Avoid uninitialized variable warning
perf test: Fix shadow stat test for non-bash shells
tools headers: Syncronize linux/build_bug.h with the kernel sources
tools headers UAPI: Sync kvm.h headers with the kernel sources
perf bpf examples: Fix bpf.h header include directive in 5sec.c example
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Following patch add support for flow based tunneling API
to send and recv GTP tunnel packet over tunnel metadata API.
This would allow this device integration with OVS or eBPF using
flow based tunneling APIs.
Signed-off-by: Pravin B Shelar <pbshelar@fb.com>
Link: https://lore.kernel.org/r/20210110070021.26822-1-pbshelar@fb.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Daniel Borkmann says:
====================
pull-request: bpf-next 2021-01-16
1) Extend atomic operations to the BPF instruction set along with x86-64 JIT support,
that is, atomic{,64}_{xchg,cmpxchg,fetch_{add,and,or,xor}}, from Brendan Jackman.
2) Add support for using kernel module global variables (__ksym externs in BPF
programs) retrieved via module's BTF, from Andrii Nakryiko.
3) Generalize BPF stackmap's buildid retrieval and add support to have buildid
stored in mmap2 event for perf, from Jiri Olsa.
4) Various fixes for cross-building BPF sefltests out-of-tree which then will
unblock wider automated testing on ARM hardware, from Jean-Philippe Brucker.
5) Allow to retrieve SOL_SOCKET opts from sock_addr progs, from Daniel Borkmann.
6) Clean up driver's XDP buffer init and split into two helpers to init per-
descriptor and non-changing fields during processing, from Lorenzo Bianconi.
7) Minor misc improvements to libbpf & bpftool, from Ian Rogers.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (41 commits)
perf: Add build id data in mmap2 event
bpf: Add size arg to build_id_parse function
bpf: Move stack_map_get_build_id into lib
bpf: Document new atomic instructions
bpf: Add tests for new BPF atomic operations
bpf: Add bitwise atomic instructions
bpf: Pull out a macro for interpreting atomic ALU operations
bpf: Add instructions for atomic_[cmp]xchg
bpf: Add BPF_FETCH field / create atomic_fetch_add instruction
bpf: Move BPF_STX reserved field check into BPF_STX verifier code
bpf: Rename BPF_XADD and prepare to encode other atomics in .imm
bpf: x86: Factor out a lookup table for some ALU opcodes
bpf: x86: Factor out emission of REX byte
bpf: x86: Factor out emission of ModR/M for *(reg + off)
tools/bpftool: Add -Wall when building BPF programs
bpf, libbpf: Avoid unused function warning on bpf_tail_call_static
selftests/bpf: Install btf_dump test cases
selftests/bpf: Fix installation of urandom_read
selftests/bpf: Move generated test files to $(TEST_GEN_FILES)
selftests/bpf: Fix out-of-tree build
...
====================
Link: https://lore.kernel.org/r/20210116012922.17823-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Daniel Borkmann says:
====================
pull-request: bpf 2021-01-16
1) Fix a double bpf_prog_put() for BPF_PROG_{TYPE_EXT,TYPE_TRACING} types in
link creation's error path causing a refcount underflow, from Jiri Olsa.
2) Fix BTF validation errors for the case where kernel modules don't declare
any new types and end up with an empty BTF, from Andrii Nakryiko.
3) Fix BPF local storage helpers to first check their {task,inode} owners for
being NULL before access, from KP Singh.
4) Fix a memory leak in BPF setsockopt handling for the case where optlen is
zero and thus temporary optval buffer should be freed, from Stanislav Fomichev.
5) Fix a syzbot memory allocation splat in BPF_PROG_TEST_RUN infra for
raw_tracepoint caused by too big ctx_size_in, from Song Liu.
6) Fix LLVM code generation issues with verifier where PTR_TO_MEM{,_OR_NULL}
registers were spilled to stack but not recognized, from Gilad Reti.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
MAINTAINERS: Update my email address
selftests/bpf: Add verifier test for PTR_TO_MEM spill
bpf: Support PTR_TO_MEM{,_OR_NULL} register spilling
bpf: Reject too big ctx_size_in for raw_tp test run
libbpf: Allow loading empty BTFs
bpf: Allow empty module BTFs
bpf: Don't leak memory in bpf getsockopt when optlen == 0
bpf: Update local storage test to check handling of null ptrs
bpf: Fix typo in bpf_inode_storage.c
bpf: Local storage helpers should check nullness of owner ptr passed
bpf: Prevent double bpf_prog_put call from bpf_tracing_prog_attach
====================
Link: https://lore.kernel.org/r/20210116002025.15706-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Catalin Marinas:
- Set the minimum GCC version to 5.1 for arm64 due to earlier compiler
bugs.
- Make atomic helpers __always_inline to avoid a section mismatch when
compiling with clang.
- Fix the CMA and crashkernel reservations to use ZONE_DMA (remove the
arm64_dma32_phys_limit variable, no longer needed with a dynamic
ZONE_DMA sizing in 5.11).
- Remove redundant IRQ flag tracing that was leaving lockdep
inconsistent with the hardware state.
- Revert perf events based hard lockup detector that was causing
smp_processor_id() to be called in preemptible context.
- Some trivial cleanups - spelling fix, renaming S_FRAME_SIZE to
PT_REGS_SIZE, function prototypes added.
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: selftests: Fix spelling of 'Mismatch'
arm64: syscall: include prototype for EL0 SVC functions
compiler.h: Raise minimum version of GCC to 5.1 for arm64
arm64: make atomic helpers __always_inline
arm64: rename S_FRAME_SIZE to PT_REGS_SIZE
Revert "arm64: Enable perf events based hard lockup detector"
arm64: entry: remove redundant IRQ flag tracing
arm64: Remove arm64_dma32_phys_limit and its uses
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When 'perf inject' reads a perf.data file from an older version of perf,
it writes event attributes into the output with the original size field,
but lays them out as if they had the size currently used. Readers see a
corrupt file. Update the size field to match the layout.
Signed-off-by: Al Grant <al.grant@foss.arm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20201124195818.30603-1-al.grant@arm.com
Signed-off-by: Denis Nikitin <denik@chromium.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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In some cases, the number of cpus (nr_cpus_online) is confused with the
maximum cpu number (nr_cpus_avail), which results in the error in the
example below:
Example on system with 8 cpus:
Before:
# echo 0 > /sys/devices/system/cpu/cpu2/online
# ./perf record --kcore -e intel_pt// taskset --cpu-list 7 uname
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.147 MB perf.data ]
# ./perf script --itrace=e
Requested CPU 7 too large. Consider raising MAX_NR_CPUS
0x25908 [0x8]: failed to process type: 68 [Invalid argument]
After:
# ./perf script --itrace=e
#
Fixes: 8c7274691f0d ("perf machine: Replace MAX_NR_CPUS with perf_env::nr_cpus_online")
Fixes: 7df4e36a4785 ("perf session: Replace MAX_NR_CPUS with perf_env::nr_cpus_online")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/20210107174159.24897-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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As of now it doesn't consider cgroups when collecting shadow stats and
metrics so counter values from different cgroups will be saved in a same
slot. This resulted in incorrect numbers when those cgroups have
different workloads.
For example, let's look at the scenario below: cgroups A and C runs same
workload which burns a cpu while cgroup B runs a light workload.
$ perf stat -a -e cycles,instructions --for-each-cgroup A,B,C sleep 1
Performance counter stats for 'system wide':
3,958,116,522 cycles A
6,722,650,929 instructions A # 2.53 insn per cycle
1,132,741 cycles B
571,743 instructions B # 0.00 insn per cycle
4,007,799,935 cycles C
6,793,181,523 instructions C # 2.56 insn per cycle
1.001050869 seconds time elapsed
When I run 'perf stat' with single workload, it usually shows IPC around
1.7. We can verify it (6,722,650,929.0 / 3,958,116,522 = 1.698) for cgroup A.
But in this case, since cgroups are ignored, cycles are averaged so it
used the lower value for IPC calculation and resulted in around 2.5.
avg cycle: (3958116522 + 1132741 + 4007799935) / 3 = 2655683066
IPC (A) : 6722650929 / 2655683066 = 2.531
IPC (B) : 571743 / 2655683066 = 0.0002
IPC (C) : 6793181523 / 2655683066 = 2.557
We can simply compare cgroup pointers in the evsel and it'll be NULL
when cgroups are not specified. With this patch, I can see correct
numbers like below:
$ perf stat -a -e cycles,instructions --for-each-cgroup A,B,C sleep 1
Performance counter stats for 'system wide':
4,171,051,687 cycles A
7,219,793,922 instructions A # 1.73 insn per cycle
1,051,189 cycles B
583,102 instructions B # 0.55 insn per cycle
4,171,124,710 cycles C
7,192,944,580 instructions C # 1.72 insn per cycle
1.007909814 seconds time elapsed
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20210115071139.257042-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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To pass more info to the saved_value in the runtime_stat, add a new
struct runtime_stat_data. Currently it only has 'ctx' field but later
patch will add more.
Note that we intentionally pass 0 as ctx to clock-related events for
compatibility. It was already there in a few places. So move the code
into the saved_value_lookup() explicitly and add a comment.
Suggested-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20210115071139.257042-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Permissions are necessary to get a tracepoint id. Fail the test when the
read fails.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20210114180250.3853825-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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If a test fails return -1 rather than 0. This is consistent with the
return value in test-cpumap.c
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20210114180250.3853825-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The variable 'bf' is read (for a write call) without being initialized
triggering a memory sanitizer warning. Use 'bf' in the read and switch
the write to reading from a string.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20210114212304.4018119-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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It was using some bash-specific features and failed to parse when
running with a different shell like below:
root@kbl-ppc:~/kbl-ws/perf-dev/lck-9077/acme.tmp/tools/perf# ./perf test 83 -vv
83: perf stat metrics (shadow stat) test :
--- start ---
test child forked, pid 3922
./tests/shell/stat+shadow_stat.sh: 19: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 24: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 30: ./tests/shell/stat+shadow_stat.sh: [[: not found
(standard_in) 2: syntax error
./tests/shell/stat+shadow_stat.sh: 36: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 19: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 24: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 30: ./tests/shell/stat+shadow_stat.sh: [[: not found
(standard_in) 2: syntax error
./tests/shell/stat+shadow_stat.sh: 36: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 45: ./tests/shell/stat+shadow_stat.sh: declare: not found
test child finished with -1
---- end ----
perf stat metrics (shadow stat) test: FAILED!
Reported-by: Jin Yao <yao.jin@linux.intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Laight <david.laight@aculab.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20210114050609.1258820-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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To pick up the changes in:
3a176b94609a18f5 ("Revert "kbuild: avoid static_assert for genksyms"")
And silence this perf build warning:
Warning: Kernel ABI header at 'tools/include/linux/build_bug.h' differs from latest version at 'include/linux/build_bug.h'
diff -u tools/include/linux/build_bug.h include/linux/build_bug.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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To pick the changes in:
647daca25d24fb6e ("KVM: SVM: Add support for booting APs in an SEV-ES guest")
That don't cause any tooling change, just silences this perf build
warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h'
diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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It was looking at bpf/bpf.h, which caused this problem:
# perf trace -e tools/perf/examples/bpf/5sec.c
/home/acme/git/perf/tools/perf/examples/bpf/5sec.c:42:10: fatal error: 'bpf/bpf.h' file not found
#include <bpf/bpf.h>
^~~~~~~~~~~
1 error generated.
ERROR: unable to compile tools/perf/examples/bpf/5sec.c
Hint: Check error message shown above.
Hint: You can also pre-compile it into .o using:
clang -target bpf -O2 -c tools/perf/examples/bpf/5sec.c
with proper -I and -D options.
event syntax error: 'tools/perf/examples/bpf/5sec.c'
\___ Failed to load tools/perf/examples/bpf/5sec.c from source: Error when compiling BPF scriptlet
#
Change that to plain bpf.h, to make it work again:
# perf trace -e tools/perf/examples/bpf/5sec.c sleep 5s
0.000 perf_bpf_probe:hrtimer_nanosleep(__probe_ip: -1776891872, rqtp: 5000000000)
# perf trace -e tools/perf/examples/bpf/5sec.c/max-stack=16/ sleep 5s
0.000 perf_bpf_probe:hrtimer_nanosleep(__probe_ip: -1776891872, rqtp: 5000000000)
hrtimer_nanosleep ([kernel.kallsyms])
common_nsleep ([kernel.kallsyms])
__x64_sys_clock_nanosleep ([kernel.kallsyms])
do_syscall_64 ([kernel.kallsyms])
entry_SYSCALL_64_after_hwframe ([kernel.kallsyms])
__clock_nanosleep_2 (/usr/lib64/libc-2.32.so)
# perf trace -e tools/perf/examples/bpf/5sec.c sleep 4s
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The SVE and FPSIMD stress tests have a spelling mistake in the output, fix
it.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210108183144.673-1-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull bootconfig fix from Steven Rostedt:
"Update bootconf scripts for tracing_on option
The tracing_on option is supported by bootconfig entries, but the
scripts to convert from ftrace to a bootconfig and back were not
updated"
* tag 'trace-v5.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tools/bootconfig: Add tracing_on support to helper scripts
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Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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The prog_test that's added depends on Clang/LLVM features added by
Yonghong in commit 286daafd6512 (was https://reviews.llvm.org/D72184).
Note the use of a define called ENABLE_ATOMICS_TESTS: this is used
to:
- Avoid breaking the build for people on old versions of Clang
- Avoid needing separate lists of test objects for no_alu32, where
atomics are not supported even if Clang has the feature.
The atomics_test.o BPF object is built unconditionally both for
test_progs and test_progs-no_alu32. For test_progs, if Clang supports
atomics, ENABLE_ATOMICS_TESTS is defined, so it includes the proper
test code. Otherwise, progs and global vars are defined anyway, as
stubs; this means that the skeleton user code still builds.
The atomics_test.o userspace object is built once and used for both
test_progs and test_progs-no_alu32. A variable called skip_tests is
defined in the BPF object's data section, which tells the userspace
object whether to skip the atomics test.
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-11-jackmanb@google.com
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This adds instructions for
atomic[64]_[fetch_]and
atomic[64]_[fetch_]or
atomic[64]_[fetch_]xor
All these operations are isomorphic enough to implement with the same
verifier, interpreter, and x86 JIT code, hence being a single commit.
The main interesting thing here is that x86 doesn't directly support
the fetch_ version these operations, so we need to generate a CMPXCHG
loop in the JIT. This requires the use of two temporary registers,
IIUC it's safe to use BPF_REG_AX and x86's AUX_REG for this purpose.
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-10-jackmanb@google.com
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This adds two atomic opcodes, both of which include the BPF_FETCH
flag. XCHG without the BPF_FETCH flag would naturally encode
atomic_set. This is not supported because it would be of limited
value to userspace (it doesn't imply any barriers). CMPXCHG without
BPF_FETCH woulud be an atomic compare-and-write. We don't have such
an operation in the kernel so it isn't provided to BPF either.
There are two significant design decisions made for the CMPXCHG
instruction:
- To solve the issue that this operation fundamentally has 3
operands, but we only have two register fields. Therefore the
operand we compare against (the kernel's API calls it 'old') is
hard-coded to be R0. x86 has similar design (and A64 doesn't
have this problem).
A potential alternative might be to encode the other operand's
register number in the immediate field.
- The kernel's atomic_cmpxchg returns the old value, while the C11
userspace APIs return a boolean indicating the comparison
result. Which should BPF do? A64 returns the old value. x86 returns
the old value in the hard-coded register (and also sets a
flag). That means return-old-value is easier to JIT, so that's
what we use.
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-8-jackmanb@google.com
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The BPF_FETCH field can be set in bpf_insn.imm, for BPF_ATOMIC
instructions, in order to have the previous value of the
atomically-modified memory location loaded into the src register
after an atomic op is carried out.
Suggested-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-7-jackmanb@google.com
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