Commit Graph

30456 Commits

Author SHA1 Message Date
Andrii Nakryiko
03d5b99138 libbpf: Cleanup struct bpf_core_cand.
Remove two redundant fields from struct bpf_core_cand.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211201181040.23337-8-alexei.starovoitov@gmail.com
2021-12-02 11:18:35 -08:00
Alexei Starovoitov
fbd94c7afc bpf: Pass a set of bpf_core_relo-s to prog_load command.
struct bpf_core_relo is generated by llvm and processed by libbpf.
It's a de-facto uapi.
With CO-RE in the kernel the struct bpf_core_relo becomes uapi de-jure.
Add an ability to pass a set of 'struct bpf_core_relo' to prog_load command
and let the kernel perform CO-RE relocations.

Note the struct bpf_line_info and struct bpf_func_info have the same
layout when passed from LLVM to libbpf and from libbpf to the kernel
except "insn_off" fields means "byte offset" when LLVM generates it.
Then libbpf converts it to "insn index" to pass to the kernel.
The struct bpf_core_relo's "insn_off" field is always "byte offset".

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211201181040.23337-6-alexei.starovoitov@gmail.com
2021-12-02 11:18:35 -08:00
Alexei Starovoitov
46334a0cd2 bpf: Define enum bpf_core_relo_kind as uapi.
enum bpf_core_relo_kind is generated by llvm and processed by libbpf.
It's a de-facto uapi.
With CO-RE in the kernel the bpf_core_relo_kind values become uapi de-jure.
Also rename them with BPF_CORE_ prefix to distinguish from conflicting names in
bpf_core_read.h. The enums bpf_field_info_kind, bpf_type_id_kind,
bpf_type_info_kind, bpf_enum_value_kind are passing different values from bpf
program into llvm.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211201181040.23337-5-alexei.starovoitov@gmail.com
2021-12-02 11:18:35 -08:00
Alexei Starovoitov
29db4bea1d bpf: Prepare relo_core.c for kernel duty.
Make relo_core.c to be compiled for the kernel and for user space libbpf.

Note the patch is reducing BPF_CORE_SPEC_MAX_LEN from 64 to 32.
This is the maximum number of nested structs and arrays.
For example:
 struct sample {
     int a;
     struct {
         int b[10];
     };
 };

 struct sample *s = ...;
 int *y = &s->b[5];
This field access is encoded as "0:1:0:5" and spec len is 4.

The follow up patch might bump it back to 64.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211201181040.23337-4-alexei.starovoitov@gmail.com
2021-12-02 11:18:34 -08:00
Alexei Starovoitov
74753e1462 libbpf: Replace btf__type_by_id() with btf_type_by_id().
To prepare relo_core.c to be compiled in the kernel and the user space
replace btf__type_by_id with btf_type_by_id.

In libbpf btf__type_by_id and btf_type_by_id have different behavior.

bpf_core_apply_relo_insn() needs behavior of uapi btf__type_by_id
vs internal btf_type_by_id, but type_id range check is already done
in bpf_core_apply_relo(), so it's safe to replace it everywhere.
The kernel btf_type_by_id() does the check anyway. It doesn't hurt.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211201181040.23337-2-alexei.starovoitov@gmail.com
2021-12-02 11:18:34 -08:00
Li Zhijian
36d7d36fcf selftests: net: remove meaningless help option
$ ./fcnal-test.sh -t help
Test names: help

Looks it intent to list the available tests but it didn't do the right
thing. I will add another option the do that in the later patch.

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-02 13:12:27 +00:00
Li Zhijian
a05431b22b selftests: net: Correct case name
ipv6_addr_bind/ipv4_addr_bind are function names. Previously, bind test
would not be run by default due to the wrong case names

Fixes: 34d0302ab8 ("selftests: Add ipv6 address bind tests to fcnal-test")
Fixes: 75b2b2b3db ("selftests: Add ipv4 address bind tests to fcnal-test")
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-02 12:19:08 +00:00
Boqun Feng
c438b7d860 tools/memory-model: litmus: Add two tests for unlock(A)+lock(B) ordering
The memory model has been updated to provide a stronger ordering
guarantee for unlock(A)+lock(B) on the same CPU/thread. Therefore add
two litmus tests describing this new guarantee, these tests are simple
yet can clearly show the usage of the new guarantee, also they can serve
as the self tests for the modification in the model.

Co-developed-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:47:08 -08:00
Boqun Feng
b47c05ecf6 tools/memory-model: doc: Describe the requirement of the litmus-tests directory
It's better that we have some "standard" about which test should be put
in the litmus-tests directory because it helps future contributors
understand whether they should work on litmus-tests in kernel or Paul's
GitHub repo. Therefore explain a little bit on what a "representative"
litmus test is.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:47:08 -08:00
Boqun Feng
ddfe12944e tools/memory-model: Provide extra ordering for unlock+lock pair on the same CPU
A recent discussion[1] shows that we are in favor of strengthening the
ordering of unlock + lock on the same CPU: a unlock and a po-after lock
should provide the so-called RCtso ordering, that is a memory access S
po-before the unlock should be ordered against a memory access R
po-after the lock, unless S is a store and R is a load.

The strengthening meets programmers' expection that "sequence of two
locked regions to be ordered wrt each other" (from Linus), and can
reduce the mental burden when using locks. Therefore add it in LKMM.

[1]: https://lore.kernel.org/lkml/20210909185937.GA12379@rowland.harvard.edu/

Co-developed-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> (RISC-V)
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:47:08 -08:00
Paul E. McKenney
90b21bcfb2 torture: Properly redirect kvm-remote.sh "echo" commands
The echo commands following initialization of the "oldrun" variable need
to be "tee"d to $oldrun/remote-log.  This commit fixes several stragglers.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:30:29 -08:00
Paul E. McKenney
b6c9dbf04f torture: Fix incorrectly redirected "exit" in kvm-remote.sh
The "exit 4" in kvm-remote.sh is pointlessly redirected, so this commit
removes the redirection.

Fixes: 0092eae4cb ("torture: Add kvm-remote.sh script for distributed rcutorture test runs")
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:30:29 -08:00
Paul E. McKenney
a959ed627a rcutorture: Test RCU Tasks lock-contention detection
This commit adjusts the TRACE02 scenario to use a pair of callback-flood
kthreads.  This in turn forces lock contention on the single RCU Tasks
Trace callback queue, which forces use of all CPUs' queues, thus testing
this transition.  (No, there is not yet any way to transition back.

Cc: Neeraj Upadhyay <neeraj.iitr10@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:30:29 -08:00
Paul E. McKenney
4ead4e3319 rcutorture: Cause TREE02 and TREE10 scenarios to do more callback flooding
This commit enables two callback-flood kthreads for the TREE02 scenario
and 28 for the TREE10 scenario.

Cc: Neeraj Upadhyay <neeraj.iitr10@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:30:29 -08:00
Paul E. McKenney
f61537009e torture: Retry download once before giving up
Currently, a transient network error can kill a run if it happens while
downloading the tarball to one of the target systems.  This commit
therefore does a 60-second wait and then a retry.  If further experience
indicates, a more elaborate mechanism might be used later.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:30:29 -08:00
Paul E. McKenney
c06354a121 torture: Make kvm-find-errors.sh report link-time undefined symbols
This commit makes kvm-find-errors.sh check for and report undefined
symbols that are detected at link time.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:30:28 -08:00
Paul E. McKenney
b6a4fd35d2 torture: Catch kvm.sh help text up with actual options
This commit brings the kvm.sh script's help text up to date with recently
(and some not-so-recently) added parameters.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:30:28 -08:00
Mark Brown
b0fe9dec66 tools/nolibc: Implement gettid()
Allow test programs to determine their thread ID.

Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:26:42 -08:00
Ammar Faizi
7bdc0e7a39 tools/nolibc: x86-64: Use mov $60,%eax instead of mov $60,%rax
Note that mov to 32-bit register will zero extend to 64-bit register.
Thus `mov $60,%eax` has the same effect with `mov $60,%rax`. Use the
shorter opcode to achieve the same thing.
```
  b8 3c 00 00 00       	mov    $60,%eax (5 bytes) [1]
  48 c7 c0 3c 00 00 00 	mov    $60,%rax (7 bytes) [2]
```
Currently, we use [2]. Change it to [1] for shorter code.

Signed-off-by: Ammar Faizi <ammar.faizi@students.amikom.ac.id>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:26:42 -08:00
Ammar Faizi
bf91666959 tools/nolibc: x86: Remove r8, r9 and r10 from the clobber list
Linux x86-64 syscall only clobbers rax, rcx and r11 (and "memory").

  - rax for the return value.
  - rcx to save the return address.
  - r11 to save the rflags.

Other registers are preserved.

Having r8, r9 and r10 in the syscall clobber list is harmless, but this
results in a missed-optimization.

As the syscall doesn't clobber r8-r10, GCC should be allowed to reuse
their value after the syscall returns to userspace. But since they are
in the clobber list, GCC will always miss this opportunity.

Remove them from the x86-64 syscall clobber list to help GCC generate
better code and fix the comment.

See also the x86-64 ABI, section A.2 AMD64 Linux Kernel Conventions,
A.2.1 Calling Conventions [1].

Extra note:
Some people may think it does not really give a benefit to remove r8,
r9 and r10 from the syscall clobber list because the impression of
syscall is a C function call, and function call always clobbers those 3.

However, that is not the case for nolibc.h, because we have a potential
to inline the "syscall" instruction (which its opcode is "0f 05") to the
user functions.

All syscalls in the nolibc.h are written as a static function with inline
ASM and are likely always inline if we use optimization flag, so this is
a profit not to have r8, r9 and r10 in the clobber list.

Here is the example where this matters.

Consider the following C code:
```
  #include "tools/include/nolibc/nolibc.h"
  #define read_abc(a, b, c) __asm__ volatile("nop"::"r"(a),"r"(b),"r"(c))

  int main(void)
  {
  	int a = 0xaa;
  	int b = 0xbb;
  	int c = 0xcc;

  	read_abc(a, b, c);
  	write(1, "test\n", 5);
  	read_abc(a, b, c);

  	return 0;
  }
```

Compile with:
    gcc -Os test.c -o test -nostdlib

With r8, r9, r10 in the clobber list, GCC generates this:

0000000000001000 <main>:
    1000:	f3 0f 1e fa          	endbr64
    1004:	41 54                	push   %r12
    1006:	41 bc cc 00 00 00    	mov    $0xcc,%r12d
    100c:	55                   	push   %rbp
    100d:	bd bb 00 00 00       	mov    $0xbb,%ebp
    1012:	53                   	push   %rbx
    1013:	bb aa 00 00 00       	mov    $0xaa,%ebx
    1018:	90                   	nop
    1019:	b8 01 00 00 00       	mov    $0x1,%eax
    101e:	bf 01 00 00 00       	mov    $0x1,%edi
    1023:	ba 05 00 00 00       	mov    $0x5,%edx
    1028:	48 8d 35 d1 0f 00 00 	lea    0xfd1(%rip),%rsi
    102f:	0f 05                	syscall
    1031:	90                   	nop
    1032:	31 c0                	xor    %eax,%eax
    1034:	5b                   	pop    %rbx
    1035:	5d                   	pop    %rbp
    1036:	41 5c                	pop    %r12
    1038:	c3                   	ret

GCC thinks that syscall will clobber r8, r9, r10. So it spills 0xaa,
0xbb and 0xcc to callee saved registers (r12, rbp and rbx). This is
clearly extra memory access and extra stack size for preserving them.

But syscall does not actually clobber them, so this is a missed
optimization.

Now without r8, r9, r10 in the clobber list, GCC generates better code:

0000000000001000 <main>:
    1000:	f3 0f 1e fa          	endbr64
    1004:	41 b8 aa 00 00 00    	mov    $0xaa,%r8d
    100a:	41 b9 bb 00 00 00    	mov    $0xbb,%r9d
    1010:	41 ba cc 00 00 00    	mov    $0xcc,%r10d
    1016:	90                   	nop
    1017:	b8 01 00 00 00       	mov    $0x1,%eax
    101c:	bf 01 00 00 00       	mov    $0x1,%edi
    1021:	ba 05 00 00 00       	mov    $0x5,%edx
    1026:	48 8d 35 d3 0f 00 00 	lea    0xfd3(%rip),%rsi
    102d:	0f 05                	syscall
    102f:	90                   	nop
    1030:	31 c0                	xor    %eax,%eax
    1032:	c3                   	ret

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Acked-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Ammar Faizi <ammar.faizi@students.amikom.ac.id>
Link: https://gitlab.com/x86-psABIs/x86-64-ABI/-/wikis/x86-64-psABI [1]
Link: https://lore.kernel.org/lkml/20211011040344.437264-1-ammar.faizi@students.amikom.ac.id/
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:26:42 -08:00
Willy Tarreau
de0244ae40 tools/nolibc: fix incorrect truncation of exit code
Ammar Faizi reported that our exit code handling is wrong. We truncate
it to the lowest 8 bits but the syscall itself is expected to take a
regular 32-bit signed integer, not an unsigned char. It's the kernel
that later truncates it to the lowest 8 bits. The difference is visible
in strace, where the program below used to show exit(255) instead of
exit(-1):

  int main(void)
  {
        return -1;
  }

This patch applies the fix to all archs. x86_64, i386, arm64, armv7 and
mips were all tested and confirmed to work fine now. Risc-v was not
tested but the change is trivial and exactly the same as for other archs.

Reported-by: Ammar Faizi <ammar.faizi@students.amikom.ac.id>
Cc: stable@vger.kernel.org
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:26:42 -08:00
Willy Tarreau
ebbe0d8a44 tools/nolibc: i386: fix initial stack alignment
After re-checking in the spec and comparing stack offsets with glibc,
The last pushed argument must be 16-byte aligned (i.e. aligned before the
call) so that in the callee esp+4 is multiple of 16, so the principle is
the 32-bit equivalent to what Ammar fixed for x86_64. It's possible that
32-bit code using SSE2 or MMX could have been affected. In addition the
frame pointer ought to be zero at the deepest level.

Link: https://gitlab.com/x86-psABIs/i386-ABI/-/wikis/Intel386-psABI
Cc: Ammar Faizi <ammar.faizi@students.amikom.ac.id>
Cc: stable@vger.kernel.org
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:26:42 -08:00
Ammar Faizi
937ed91c71 tools/nolibc: x86-64: Fix startup code bug
Before this patch, the `_start` function looks like this:
```
0000000000001170 <_start>:
    1170:	pop    %rdi
    1171:	mov    %rsp,%rsi
    1174:	lea    0x8(%rsi,%rdi,8),%rdx
    1179:	and    $0xfffffffffffffff0,%rsp
    117d:	sub    $0x8,%rsp
    1181:	call   1000 <main>
    1186:	movzbq %al,%rdi
    118a:	mov    $0x3c,%rax
    1191:	syscall
    1193:	hlt
    1194:	data16 cs nopw 0x0(%rax,%rax,1)
    119f:	nop
```
Note the "and" to %rsp with $-16, it makes the %rsp be 16-byte aligned,
but then there is a "sub" with $0x8 which makes the %rsp no longer
16-byte aligned, then it calls main. That's the bug!

What actually the x86-64 System V ABI mandates is that right before the
"call", the %rsp must be 16-byte aligned, not after the "call". So the
"sub" with $0x8 here breaks the alignment. Remove it.

An example where this rule matters is when the callee needs to align
its stack at 16-byte for aligned move instruction, like `movdqa` and
`movaps`. If the callee can't align its stack properly, it will result
in segmentation fault.

x86-64 System V ABI also mandates the deepest stack frame should be
zero. Just to be safe, let's zero the %rbp on startup as the content
of %rbp may be unspecified when the program starts. Now it looks like
this:
```
0000000000001170 <_start>:
    1170:	pop    %rdi
    1171:	mov    %rsp,%rsi
    1174:	lea    0x8(%rsi,%rdi,8),%rdx
    1179:	xor    %ebp,%ebp                # zero the %rbp
    117b:	and    $0xfffffffffffffff0,%rsp # align the %rsp
    117f:	call   1000 <main>
    1184:	movzbq %al,%rdi
    1188:	mov    $0x3c,%rax
    118f:	syscall
    1191:	hlt
    1192:	data16 cs nopw 0x0(%rax,%rax,1)
    119d:	nopl   (%rax)
```

Cc: Bedirhan KURT <windowz414@gnuweeb.org>
Cc: Louvian Lyndal <louvianlyndal@gmail.com>
Reported-by: Peter Cordes <peter@cordes.ca>
Signed-off-by: Ammar Faizi <ammar.faizi@students.amikom.ac.id>
[wt: I did this on purpose due to a misunderstanding of the spec, other
     archs will thus have to be rechecked, particularly i386]
Cc: stable@vger.kernel.org
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:26:42 -08:00
Paul E. McKenney
e2c73a6860 rcu: Remove the RCU_FAST_NO_HZ Kconfig option
All of the uses of CONFIG_RCU_FAST_NO_HZ=y that I have seen involve
systems with RCU callbacks offloaded.  In this situation, all that this
Kconfig option does is slow down idle entry/exit with an additional
allways-taken early exit.  If this is the only use case, then this
Kconfig option nothing but an attractive nuisance that needs to go away.

This commit therefore removes the RCU_FAST_NO_HZ Kconfig option.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:24:47 -08:00
Paul E. McKenney
24eab6e1ff torture: Remove RCU_FAST_NO_HZ from rcu scenarios
All of the rcu scenarios that mentioning CONFIG_RCU_FAST_NO_HZ disable it.
But this Kconfig option is disabled by default, so this commit removes
the pointless "CONFIG_RCU_FAST_NO_HZ=n" lines from these scenarios.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:24:47 -08:00
Paul E. McKenney
f04cbe651b torture: Remove RCU_FAST_NO_HZ from rcuscale and refscale scenarios
All of the rcuscale and refscale scenarios that mention the Kconfig option
CONFIG_RCU_FAST_NO_HZ disable it.  But this Kconfig option is disabled by
default, so this commit removes the pointless "CONFIG_RCU_FAST_NO_HZ=n"
lines from these scenarios.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:24:46 -08:00
Paul E. McKenney
8c0abfd6d2 rcutorture: Add CONFIG_PREEMPT_DYNAMIC=n to tiny scenarios
With CONFIG_PREEMPT_DYNAMIC=y, the kernel builds with CONFIG_PREEMPTION=y
because preemption can be enabled at runtime.  This prevents any tests
of Tiny RCU or Tiny SRCU from running correctly.  This commit therefore
explicitly sets CONFIG_PREEMPT_DYNAMIC=n for those scenarios.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30 17:20:58 -08:00
Kumar Kartikeya Dwivedi
d995816b77 libbpf: Avoid reload of imm for weak, unresolved, repeating ksym
Alexei pointed out that we can use BPF_REG_0 which already contains imm
from move_blob2blob computation. Note that we now compare the second
insn's imm, but this should not matter, since both will be zeroed out
for the error case for the insn populated earlier.

Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211122235733.634914-4-memxor@gmail.com
2021-11-30 15:48:15 -08:00
Kumar Kartikeya Dwivedi
0270090d39 libbpf: Avoid double stores for success/failure case of ksym relocations
Instead, jump directly to success case stores in case ret >= 0, else do
the default 0 value store and jump over the success case. This is better
in terms of readability. Readjust the code for kfunc relocation as well
to follow a similar pattern, also leads to easier to follow code now.

Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211122235733.634914-3-memxor@gmail.com
2021-11-30 15:48:14 -08:00
Joanne Koong
ec151037af selftest/bpf/benchs: Add bpf_loop benchmark
Add benchmark to measure the throughput and latency of the bpf_loop
call.

Testing this on my dev machine on 1 thread, the data is as follows:

        nr_loops: 10
bpf_loop - throughput: 198.519 ± 0.155 M ops/s, latency: 5.037 ns/op

        nr_loops: 100
bpf_loop - throughput: 247.448 ± 0.305 M ops/s, latency: 4.041 ns/op

        nr_loops: 500
bpf_loop - throughput: 260.839 ± 0.380 M ops/s, latency: 3.834 ns/op

        nr_loops: 1000
bpf_loop - throughput: 262.806 ± 0.629 M ops/s, latency: 3.805 ns/op

        nr_loops: 5000
bpf_loop - throughput: 264.211 ± 1.508 M ops/s, latency: 3.785 ns/op

        nr_loops: 10000
bpf_loop - throughput: 265.366 ± 3.054 M ops/s, latency: 3.768 ns/op

        nr_loops: 50000
bpf_loop - throughput: 235.986 ± 20.205 M ops/s, latency: 4.238 ns/op

        nr_loops: 100000
bpf_loop - throughput: 264.482 ± 0.279 M ops/s, latency: 3.781 ns/op

        nr_loops: 500000
bpf_loop - throughput: 309.773 ± 87.713 M ops/s, latency: 3.228 ns/op

        nr_loops: 1000000
bpf_loop - throughput: 262.818 ± 4.143 M ops/s, latency: 3.805 ns/op

>From this data, we can see that the latency per loop decreases as the
number of loops increases. On this particular machine, each loop had an
overhead of about ~4 ns, and we were able to run ~250 million loops
per second.

Signed-off-by: Joanne Koong <joannekoong@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211130030622.4131246-5-joannekoong@fb.com
2021-11-30 10:56:28 -08:00
Joanne Koong
f6e659b7f9 selftests/bpf: Measure bpf_loop verifier performance
This patch tests bpf_loop in pyperf and strobemeta, and measures the
verifier performance of replacing the traditional for loop
with bpf_loop.

The results are as follows:

~strobemeta~

Baseline
    verification time 6808200 usec
    stack depth 496
    processed 554252 insns (limit 1000000) max_states_per_insn 16
    total_states 15878 peak_states 13489  mark_read 3110
    #192 verif_scale_strobemeta:OK (unrolled loop)

Using bpf_loop
    verification time 31589 usec
    stack depth 96+400
    processed 1513 insns (limit 1000000) max_states_per_insn 2
    total_states 106 peak_states 106 mark_read 60
    #193 verif_scale_strobemeta_bpf_loop:OK

~pyperf600~

Baseline
    verification time 29702486 usec
    stack depth 368
    processed 626838 insns (limit 1000000) max_states_per_insn 7
    total_states 30368 peak_states 30279 mark_read 748
    #182 verif_scale_pyperf600:OK (unrolled loop)

Using bpf_loop
    verification time 148488 usec
    stack depth 320+40
    processed 10518 insns (limit 1000000) max_states_per_insn 10
    total_states 705 peak_states 517 mark_read 38
    #183 verif_scale_pyperf600_bpf_loop:OK

Using the bpf_loop helper led to approximately a 99% decrease
in the verification time and in the number of instructions.

Signed-off-by: Joanne Koong <joannekoong@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211130030622.4131246-4-joannekoong@fb.com
2021-11-30 10:56:28 -08:00
Joanne Koong
4e5070b64b selftests/bpf: Add bpf_loop test
Add test for bpf_loop testing a variety of cases:
various nr_loops, null callback ctx, invalid flags, nested callbacks.

Signed-off-by: Joanne Koong <joannekoong@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211130030622.4131246-3-joannekoong@fb.com
2021-11-30 10:56:28 -08:00
Joanne Koong
e6f2dd0f80 bpf: Add bpf_loop helper
This patch adds the kernel-side and API changes for a new helper
function, bpf_loop:

long bpf_loop(u32 nr_loops, void *callback_fn, void *callback_ctx,
u64 flags);

where long (*callback_fn)(u32 index, void *ctx);

bpf_loop invokes the "callback_fn" **nr_loops** times or until the
callback_fn returns 1. The callback_fn can only return 0 or 1, and
this is enforced by the verifier. The callback_fn index is zero-indexed.

A few things to please note:
~ The "u64 flags" parameter is currently unused but is included in
case a future use case for it arises.
~ In the kernel-side implementation of bpf_loop (kernel/bpf/bpf_iter.c),
bpf_callback_t is used as the callback function cast.
~ A program can have nested bpf_loop calls but the program must
still adhere to the verifier constraint of its stack depth (the stack depth
cannot exceed MAX_BPF_STACK))
~ Recursive callback_fns do not pass the verifier, due to the call stack
for these being too deep.
~ The next patch will include the tests and benchmark

Signed-off-by: Joanne Koong <joannekoong@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211130030622.4131246-2-joannekoong@fb.com
2021-11-30 10:56:28 -08:00
Linus Torvalds
f080815fdb Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
 "ARM64:

   - Fix constant sign extension affecting TCR_EL2 and preventing
     running on ARMv8.7 models due to spurious bits being set

   - Fix use of helpers using PSTATE early on exit by always sampling it
     as soon as the exit takes place

   - Move pkvm's 32bit handling into a common helper

  RISC-V:

   - Fix incorrect KVM_MAX_VCPUS value

   - Unmap stage2 mapping when deleting/moving a memslot

  x86:

   - Fix and downgrade BUG_ON due to uninitialized cache

   - Many APICv and MOVE_ENC_CONTEXT_FROM fixes

   - Correctly emulate TLB flushes around nested vmentry/vmexit and when
     the nested hypervisor uses VPID

   - Prevent modifications to CPUID after the VM has run

   - Other smaller bugfixes

  Generic:

   - Memslot handling bugfixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (44 commits)
  KVM: fix avic_set_running for preemptable kernels
  KVM: VMX: clear vmx_x86_ops.sync_pir_to_irr if APICv is disabled
  KVM: SEV: accept signals in sev_lock_two_vms
  KVM: SEV: do not take kvm->lock when destroying
  KVM: SEV: Prohibit migration of a VM that has mirrors
  KVM: SEV: Do COPY_ENC_CONTEXT_FROM with both VMs locked
  selftests: sev_migrate_tests: add tests for KVM_CAP_VM_COPY_ENC_CONTEXT_FROM
  KVM: SEV: move mirror status to destination of KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM
  KVM: SEV: initialize regions_list of a mirror VM
  KVM: SEV: cleanup locking for KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM
  KVM: SEV: do not use list_replace_init on an empty list
  KVM: x86: Use a stable condition around all VT-d PI paths
  KVM: x86: check PIR even for vCPUs with disabled APICv
  KVM: VMX: prepare sync_pir_to_irr for running with APICv disabled
  KVM: selftests: page_table_test: fix calculation of guest_test_phys_mem
  KVM: x86/mmu: Handle "default" period when selectively waking kthread
  KVM: MMU: shadow nested paging does not have PKU
  KVM: x86/mmu: Remove spurious TLB flushes in TDP MMU zap collapsible path
  KVM: x86/mmu: Use yield-safe TDP MMU root iter in MMU notifier unmapping
  KVM: X86: Use vcpu->arch.walk_mmu for kvm_mmu_invlpg()
  ...
2021-11-30 09:22:15 -08:00
Matthew Wilcox (Oracle)
d6e6a27d96 tools: Fix math.h breakage
Commit 98e1385ef2 ("include/linux/radix-tree.h: replace kernel.h with
the necessary inclusions") broke the radix tree test suite in two
different ways; first by including math.h which didn't exist in the
tools directory, and second by removing an implicit include of
spinlock.h before lockdep.h.  Fix both issues.

Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-30 09:14:42 -08:00
Mehrdad Arshad Rad
c291d0a4d1 libbpf: Remove duplicate assignments
There is a same action when load_attr.attach_btf_id is initialized.

Signed-off-by: Mehrdad Arshad Rad <arshad.rad@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211128193337.10628-1-arshad.rad@gmail.com
2021-11-30 15:33:57 +01:00
Hangbin Liu
5944b5abd8 Bonding: add arp_missed_max option
Currently, we use hard code number to verify if we are in the
arp_interval timeslice. But some user may want to reduce/extend
the verify timeslice. With the similar team option 'missed_max'
the uers could change that number based on their own environment.

Acked-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-30 12:15:58 +00:00
Paolo Bonzini
17d44a96f0 KVM: SEV: Prohibit migration of a VM that has mirrors
VMs that mirror an encryption context rely on the owner to keep the
ASID allocated.  Performing a KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM
would cause a dangling ASID:

1. copy context from A to B (gets ref to A)
2. move context from A to L (moves ASID from A to L)
3. close L (releases ASID from L, B still references it)

The right way to do the handoff instead is to create a fresh mirror VM
on the destination first:

1. copy context from A to B (gets ref to A)
[later] 2. close B (releases ref to A)
3. move context from A to L (moves ASID from A to L)
4. copy context from L to M

So, catch the situation by adding a count of how many VMs are
mirroring this one's encryption context.

Fixes: 0b020f5af0 ("KVM: SEV: Add support for SEV-ES intra host migration")
Message-Id: <20211123005036.2954379-11-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:54:14 -05:00
Paolo Bonzini
dc79c9f4eb selftests: sev_migrate_tests: add tests for KVM_CAP_VM_COPY_ENC_CONTEXT_FROM
I am putting the tests in sev_migrate_tests because the failure conditions are
very similar and some of the setup code can be reused, too.

The tests cover both successful creation of a mirror VM, and error
conditions.

Cc: Peter Gonda <pgonda@google.com>
Cc: Sean Christopherson <seanjc@google.com>
Message-Id: <20211123005036.2954379-9-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:54:13 -05:00
Maciej S. Szmigiero
81835ee113 KVM: selftests: page_table_test: fix calculation of guest_test_phys_mem
A kvm_page_table_test run with its default settings fails on VMX due to
memory region add failure:
> ==== Test Assertion Failure ====
>  lib/kvm_util.c:952: ret == 0
>  pid=10538 tid=10538 errno=17 - File exists
>     1  0x00000000004057d1: vm_userspace_mem_region_add at kvm_util.c:947
>     2  0x0000000000401ee9: pre_init_before_test at kvm_page_table_test.c:302
>     3   (inlined by) run_test at kvm_page_table_test.c:374
>     4  0x0000000000409754: for_each_guest_mode at guest_modes.c:53
>     5  0x0000000000401860: main at kvm_page_table_test.c:500
>     6  0x00007f82ae2d8554: ?? ??:0
>     7  0x0000000000401894: _start at ??:?
>  KVM_SET_USER_MEMORY_REGION IOCTL failed,
>  rc: -1 errno: 17
>  slot: 1 flags: 0x0
>  guest_phys_addr: 0xc0000000 size: 0x40000000

This is because the memory range that this test is trying to add
(0x0c0000000 - 0x100000000) conflicts with LAPIC mapping at 0x0fee00000.

Looking at the code it seems that guest_test_*phys*_mem variable gets
mistakenly overwritten with guest_test_*virt*_mem while trying to adjust
the former for alignment.
With the correct variable adjusted this test runs successfully.

Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Message-Id: <52e487458c3172923549bbcf9dfccfbe6faea60b.1637940473.git.maciej.szmigiero@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:12:13 -05:00
Jason A. Donenfeld
20ae1d6aa1 wireguard: device: reset peer src endpoint when netns exits
Each peer's endpoint contains a dst_cache entry that takes a reference
to another netdev. When the containing namespace exits, we take down the
socket and prevent future sockets from being created (by setting
creating_net to NULL), which removes that potential reference on the
netns. However, it doesn't release references to the netns that a netdev
cached in dst_cache might be taking, so the netns still might fail to
exit. Since the socket is gimped anyway, we can simply clear all the
dst_caches (by way of clearing the endpoint src), which will release all
references.

However, the current dst_cache_reset function only releases those
references lazily. But it turns out that all of our usages of
wg_socket_clear_peer_endpoint_src are called from contexts that are not
exactly high-speed or bottle-necked. For example, when there's
connection difficulty, or when userspace is reconfiguring the interface.
And in particular for this patch, when the netns is exiting. So for
those cases, it makes more sense to call dst_release immediately. For
that, we add a small helper function to dst_cache.

This patch also adds a test to netns.sh from Hangbin Liu to ensure this
doesn't regress.

Tested-by: Hangbin Liu <liuhangbin@gmail.com>
Reported-by: Xiumei Mu <xmu@redhat.com>
Cc: Toke Høiland-Jørgensen <toke@redhat.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Fixes: 900575aa33 ("wireguard: device: avoid circular netns references")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-29 19:50:45 -08:00
Li Zhijian
7e938beb83 wireguard: selftests: rename DEBUG_PI_LIST to DEBUG_PLIST
DEBUG_PI_LIST was renamed to DEBUG_PLIST since 8e18faeac3 ("lib/plist:
rename DEBUG_PI_LIST to DEBUG_PLIST").

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Fixes: 8e18faeac3 ("lib/plist: rename DEBUG_PI_LIST to DEBUG_PLIST")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-29 19:50:40 -08:00
Jason A. Donenfeld
782c72af56 wireguard: selftests: actually test for routing loops
We previously removed the restriction on looping to self, and then added
a test to make sure the kernel didn't blow up during a routing loop. The
kernel didn't blow up, thankfully, but on certain architectures where
skb fragmentation is easier, such as ppc64, the skbs weren't actually
being discarded after a few rounds through. But the test wasn't catching
this. So actually test explicitly for massive increases in tx to see if
we have a routing loop. Note that the actual loop problem will need to
be addressed in a different commit.

Fixes: b673e24aad ("wireguard: socket: remove errant restriction on looping to self")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-29 19:50:29 -08:00
Jason A. Donenfeld
03ff1b1def wireguard: selftests: increase default dmesg log size
The selftests currently parse the kernel log at the end to track
potential memory leaks. With these tests now reading off the end of the
buffer, due to recent optimizations, some creation messages were lost,
making the tests think that there was a free without an alloc. Fix this
by increasing the kernel log size.

Fixes: 24b70eeeb4 ("wireguard: use synchronize_net rather than synchronize_rcu")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-29 19:50:29 -08:00
Alan Maguire
43174f0d45 libbpf: Silence uninitialized warning/error in btf_dump_dump_type_data
When compiling libbpf with gcc 4.8.5, we see:

  CC       staticobjs/btf_dump.o
btf_dump.c: In function ‘btf_dump_dump_type_data.isra.24’:
btf_dump.c:2296:5: error: ‘err’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
  if (err < 0)
     ^
cc1: all warnings being treated as errors
make: *** [staticobjs/btf_dump.o] Error 1

While gcc 4.8.5 is too old to build the upstream kernel, it's possible it
could be used to build standalone libbpf which suffers from the same problem.
Silence the error by initializing 'err' to 0.  The warning/error seems to be
a false positive since err is set early in the function.  Regardless we
shouldn't prevent libbpf from building for this.

Fixes: 920d16af9b ("libbpf: BTF dumper support for typed data")
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1638180040-8037-1-git-send-email-alan.maguire@oracle.com
2021-11-29 09:36:44 -08:00
Ivan Vecera
754d71be52 selftests: net: bridge: fix typo in vlan_filtering dependency test
Prior patch:
]# TESTS=vlmc_filtering_test ./bridge_vlan_mcast.sh
TEST: Vlan multicast snooping enable                                [ OK ]
Device "bridge" does not exist.
TEST: Disable multicast vlan snooping when vlan filtering is disabled   [FAIL]
        Vlan filtering is disabled but multicast vlan snooping is still enabled

After patch:
# TESTS=vlmc_filtering_test ./bridge_vlan_mcast.sh
TEST: Vlan multicast snooping enable                                [ OK ]
TEST: Disable multicast vlan snooping when vlan filtering is disabled   [ OK ]

Fixes: f5a9dd58f4 ("selftests: net: bridge: add test for vlan_filtering dependency")
Cc: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-29 12:49:53 +00:00
Hengqi Chen
baeead213e selftests/bpf: Test BPF_MAP_TYPE_PROG_ARRAY static initialization
Add testcase for BPF_MAP_TYPE_PROG_ARRAY static initialization.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211128141633.502339-3-hengqi.chen@gmail.com
2021-11-28 22:24:57 -08:00
Hengqi Chen
341ac5ffc4 libbpf: Support static initialization of BPF_MAP_TYPE_PROG_ARRAY
Support static initialization of BPF_MAP_TYPE_PROG_ARRAY with a
syntax similar to map-in-map initialization ([0]):

    SEC("socket")
    int tailcall_1(void *ctx)
    {
        return 0;
    }

    struct {
        __uint(type, BPF_MAP_TYPE_PROG_ARRAY);
        __uint(max_entries, 2);
        __uint(key_size, sizeof(__u32));
        __array(values, int (void *));
    } prog_array_init SEC(".maps") = {
        .values = {
            [1] = (void *)&tailcall_1,
        },
    };

Here's the relevant part of libbpf debug log showing what's
going on with prog-array initialization:

libbpf: sec '.relsocket': collecting relocation for section(3) 'socket'
libbpf: sec '.relsocket': relo #0: insn #2 against 'prog_array_init'
libbpf: prog 'entry': found map 0 (prog_array_init, sec 4, off 0) for insn #0
libbpf: .maps relo #0: for 3 value 0 rel->r_offset 32 name 53 ('tailcall_1')
libbpf: .maps relo #0: map 'prog_array_init' slot [1] points to prog 'tailcall_1'
libbpf: map 'prog_array_init': created successfully, fd=5
libbpf: map 'prog_array_init': slot [1] set to prog 'tailcall_1' fd=6

  [0] Closes: https://github.com/libbpf/libbpf/issues/354

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211128141633.502339-2-hengqi.chen@gmail.com
2021-11-28 22:24:52 -08:00
Kuniyuki Iwashima
5ce7ab4961 af_unix: Remove UNIX_ABSTRACT() macro and test sun_path[0] instead.
In BSD and abstract address cases, we store sockets in the hash table with
keys between 0 and UNIX_HASH_SIZE - 1.  However, the hash saved in a socket
varies depending on its address type; sockets with BSD addresses always
have UNIX_HASH_SIZE in their unix_sk(sk)->addr->hash.

This is just for the UNIX_ABSTRACT() macro used to check the address type.
The difference of the saved hashes comes from the first byte of the address
in the first place.  So, we can test it directly.

Then we can keep a real hash in each socket and replace unix_table_lock
with per-hash locks in the later patch.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 18:01:56 -08:00
Nikolay Aleksandrov
f5a9dd58f4 selftests: net: bridge: add test for vlan_filtering dependency
Add a test for dependency of mcast_vlan_snooping on vlan_filtering. If
vlan_filtering gets disabled, then mcast_vlan_snooping must be
automatically disabled as well.

TEST: Disable multicast vlan snooping when vlan filtering is disabled   [ OK ]

Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 16:43:17 -08:00