tools/testing/selftests/net/arp_ndisc_evict_nocarrier.sh
Source file repositories/reference/linux-study-clean/tools/testing/selftests/net/arp_ndisc_evict_nocarrier.sh
File Facts
- System
- Linux kernel
- Corpus path
tools/testing/selftests/net/arp_ndisc_evict_nocarrier.sh- Extension
.sh- Size
- 5324 bytes
- Lines
- 214
- Domain
- Support Tooling And Documentation
- Bucket
- tools
- Inferred role
- Support Tooling And Documentation: tools
- Status
- atlas-only
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
- No top-level syscall, struct, function, initcall, or export declaration detected by the generator.
Annotated Snippet
#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
#
# Tests sysctl options {arp,ndisc}_evict_nocarrier={0,1}
#
# Create a veth pair and set IPs/routes on both. Then ping to establish
# an entry in the ARP/ND table. Depending on the test set sysctl option to
# 1 or 0. Set remote veth down which will cause local veth to go into a no
# carrier state. Depending on the test check the ARP/ND table:
#
# {arp,ndisc}_evict_nocarrier=1 should contain no ARP/ND after no carrier
# {arp,ndisc}_evict_nocarrer=0 should still contain the single ARP/ND entry
#
source lib.sh
readonly V4_ADDR0=10.0.10.1
readonly V4_ADDR1=10.0.10.2
readonly V6_ADDR0=2001:db8:91::1
readonly V6_ADDR1=2001:db8:91::2
nsid=100
ret=0
cleanup_v6()
{
cleanup_ns ${me} ${peer}
sysctl -w net.ipv6.conf.veth1.ndisc_evict_nocarrier=1 >/dev/null 2>&1
sysctl -w net.ipv6.conf.all.ndisc_evict_nocarrier=1 >/dev/null 2>&1
}
setup_v6() {
setup_ns me peer
IP="ip -netns ${me}"
$IP li add veth1 type veth peer name veth2
$IP li set veth1 up
$IP -6 addr add $V6_ADDR0/64 dev veth1 nodad
$IP li set veth2 netns ${peer} up
ip -netns ${peer} -6 addr add $V6_ADDR1/64 dev veth2 nodad
ip netns exec ${me} sysctl -w $1 >/dev/null 2>&1
# Establish an ND cache entry
ip netns exec ${me} ping -6 -c1 -Iveth1 $V6_ADDR1 >/dev/null 2>&1
# Should have the veth1 entry in ND table
ip netns exec ${me} ip -6 neigh get $V6_ADDR1 dev veth1 >/dev/null 2>&1
if [ $? -ne 0 ]; then
cleanup_v6
echo "failed"
exit 1
fi
# Set veth2 down, which will put veth1 in NOCARRIER state
ip netns exec ${peer} ip link set veth2 down
}
setup_v4() {
setup_ns PEER_NS
ip link add name veth0 type veth peer name veth1
ip link set dev veth0 up
ip link set dev veth1 netns "${PEER_NS}"
ip netns exec "${PEER_NS}" ip link set dev veth1 up
ip addr add $V4_ADDR0/24 dev veth0
ip netns exec "${PEER_NS}" ip addr add $V4_ADDR1/24 dev veth1
ip netns exec ${PEER_NS} ip route add default via $V4_ADDR1 dev veth1
ip route add default via $V4_ADDR0 dev veth0
sysctl -w "$1" >/dev/null 2>&1
Annotation
- Atlas domain: Support Tooling And Documentation / tools.
- Implementation status: atlas-only.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.