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RoCE GID entries become stale when netdev properties change during the
IB device registration window. This is reproducible with a udev rule
that sets a MAC address when a VF netdev appears:
ACTION=="add", SUBSYSTEM=="net", KERNEL=="eth4", \
RUN+="/sbin/ip link set eth4 address 88:22:33:44:55:66"
After VF creation, show_gids displays GIDs derived from the original
random MAC rather than the configured one.
The root cause is a race between netdev event processing and device
registration:
CPU 0 (driver) CPU 1 (udev/workqueue)
────────────── ──────────────────────
ib_register_device()
ib_cache_setup_one()
gid_table_setup_one()
_gid_table_setup_one()
← GID table allocated
rdma_roce_rescan_device()
← GIDs populated with
OLD MAC
ip link set eth4 addr NEW_MAC
NETDEV_CHANGEADDR queued
netdevice_event_work_handler()
ib_enum_all_roce_netdevs()
← Iterates DEVICE_REGISTERED
← Device NOT marked yet, SKIP!
enable_device_and_get()
xa_set_mark(DEVICE_REGISTERED)
← Too late, event was lost
The netdev event handler uses ib_enum_all_roce_netdevs() which only
iterates devices marked DEVICE_REGISTERED. However, this mark is set
late in the registration process, after the GID cache is already
populated. Events arriving in this window are silently dropped.
Fix this by introducing a new xarray mark DEVICE_GID_UPDATES that is
set immediately after the GID table is allocated and initialized. Use
the new mark in ib_enum_all_roce_netdevs() function to iterate devices
instead of DEVICE_REGISTERED.
This is safe because:
- After _gid_table_setup_one(), all required structures exist (port_data,
immutable, cache.gid)
- The GID table mutex serializes concurrent access between the initial
rescan and event handlers
- Event handlers correctly update stale GIDs even when racing with rescan
- The mark is cleared in ib_cache_cleanup_one() before teardown
This also fixes similar races for IP address events (inetaddr_event,
inet6addr_event) which use the same enumeration path.
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .clippy.toml | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .pylintrc | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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