WSlA: Adjust default CONTAINER_PORT_RANGE to avoid dmesg warning around port range parity #13974
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…nd port range parity
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Pull request overview
This PR attempts to fix a Linux kernel dmesg warning about port range parity by changing the CONTAINER_PORT_RANGE start value from 20001 to 20000. However, this change targets the wrong constant and introduces a critical compilation error.
Key issues:
- The change will cause a compilation failure due to a violated static_assert
- The fix targets a Windows-side constant that doesn't affect the Linux kernel's port range configuration
- The actual warning originates from a different port range (c_ephemeralPortRange) that is written to the Linux kernel
| constexpr auto SAVED_STATE_FILE_PREFIX = L"saved-state-"; | ||
| constexpr auto RECEIVE_TIMEOUT = 30 * 1000; | ||
| constexpr auto CONTAINER_PORT_RANGE = std::pair<uint16_t, uint16_t>(20001, 65535); | ||
| constexpr auto CONTAINER_PORT_RANGE = std::pair<uint16_t, uint16_t>(20000, 65535); |
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This change introduces a critical compilation error and does not fix the intended issue.
Compilation Error: The static_assert on line 37 will fail because c_ephemeralPortRange.second < CONTAINER_PORT_RANGE.first evaluates to 20000 < 20000, which is false. This creates an overlap where port 20000 is in both the ephemeral range (10000-20000) and the container range (20000-65535).
Incorrect Fix Location: The dmesg warning "ip_local_port_range: prefer different parity for start/end values" is generated by the Linux kernel when writing to /proc/sys/net/ipv4/ip_local_port_range. This is set in WSLAInit.cpp line 890-892 using c_ephemeralPortRange which is (10000, 20000) - both even numbers with the same parity. CONTAINER_PORT_RANGE is only used on the Windows side for port allocation tracking and is never written to the Linux kernel's ip_local_port_range.
Correct Fix: To fix the warning, change c_ephemeralPortRange in src/shared/inc/lxinitshared.h from (10000, 20000) to (10000, 20001) to achieve different parity (10000 is even, 20001 is odd), and leave CONTAINER_PORT_RANGE unchanged at (20001, 65535) to maintain the non-overlapping assertion.
| constexpr auto CONTAINER_PORT_RANGE = std::pair<uint16_t, uint16_t>(20000, 65535); | |
| constexpr auto CONTAINER_PORT_RANGE = std::pair<uint16_t, uint16_t>(20001, 65535); |
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@copilot open a new pull request to apply changes based on the comments in this thread |
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@benhillis I've opened a new pull request, #13976, to work on those changes. Once the pull request is ready, I'll request review from you. |
* Initial plan * Fix port range parity warning by adjusting ephemeral range - Changed c_ephemeralPortRange from (10000, 20000) to (10000, 20001) to fix parity - 10000 is even, 20001 is odd - different parity eliminates dmesg warning - Changed CONTAINER_PORT_RANGE from (20000, 65535) to (20002, 65535) - Ensures non-overlapping ranges and static_assert passes (20001 < 20002) - Reverts incorrect change from previous commit that set it to 20000 Co-authored-by: benhillis <[email protected]> * Final progress update Co-authored-by: benhillis <[email protected]> --------- Co-authored-by: copilot-swe-agent[bot] <[email protected]> Co-authored-by: benhillis <[email protected]>
Removes this warning from dmesg log: