caf62492f4
Remove invalid assumption in libbpf that .bss map doesn't have to be updated
in kernel. With addition of skeleton and memory-mapped initialization image,
.bss doesn't have to be all zeroes when BPF map is created, because user-code
might have initialized those variables from user-space.
Fixes: eba9c5f498a1 ("libbpf: Refactor global data map initialization")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200612194504.557844-1-andriin@fb.com
58 lines
959 B
C
58 lines
959 B
C
// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2019 Facebook */
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#include <stdbool.h>
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#include <linux/bpf.h>
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#include <bpf/bpf_helpers.h>
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struct s {
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int a;
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long long b;
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} __attribute__((packed));
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/* .data section */
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int in1 = -1;
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long long in2 = -1;
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/* .bss section */
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char in3 = '\0';
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long long in4 __attribute__((aligned(64))) = 0;
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struct s in5 = {};
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/* .rodata section */
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const volatile int in6 = 0;
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/* .data section */
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int out1 = -1;
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long long out2 = -1;
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/* .bss section */
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char out3 = 0;
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long long out4 = 0;
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int out6 = 0;
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extern bool CONFIG_BPF_SYSCALL __kconfig;
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extern int LINUX_KERNEL_VERSION __kconfig;
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bool bpf_syscall = 0;
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int kern_ver = 0;
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SEC("raw_tp/sys_enter")
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int handler(const void *ctx)
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{
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static volatile struct s out5;
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out1 = in1;
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out2 = in2;
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out3 = in3;
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out4 = in4;
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out5 = in5;
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out6 = in6;
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bpf_syscall = CONFIG_BPF_SYSCALL;
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kern_ver = LINUX_KERNEL_VERSION;
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return 0;
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}
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char _license[] SEC("license") = "GPL";
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