x/sys/unix: TestIoctlGetEthtoolDrvinfo failures

[gopherbot]

#!watchflakes
default <- pkg == "golang.org/x/sys/unix" && test == "TestIoctlGetEthtoolDrvinfo"

Issue created automatically to collect these failures.

Example (log):

=== RUN   TestIoctlGetEthtoolDrvinfo
    syscall_linux_test.go:61: end0: "st_gmac"
    syscall_linux_test.go:57: failed to get ethtool driver info for "end1": device or resource busy
--- FAIL: TestIoctlGetEthtoolDrvinfo (0.00s)

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "golang.org/x/sys/unix" && test == "TestIoctlGetEthtoolDrvinfo"

2024-05-09 17:46 x_sys-gotip-linux-riscv64 sys@f34bb9fc go@f43d9c40 x/sys/unix.TestIoctlGetEthtoolDrvinfo (log)

=== RUN   TestIoctlGetEthtoolDrvinfo
    syscall_linux_test.go:61: end0: "st_gmac"
    syscall_linux_test.go:57: failed to get ethtool driver info for "end1": device or resource busy
--- FAIL: TestIoctlGetEthtoolDrvinfo (0.00s)

— watchflakes

[mengzhuo]

It looks like a kernel bug to me.
dmesg shows DMA init failed.

[   46.926773] starfive-eth-plat 16040000.ethernet end1: PHY [stmmac-1:00] driver [YT8531 Gigabit Ethernet] (irq=POLL
)
[   46.939479] starfive-eth-plat 16040000.ethernet end1: Register MEM_TYPE_PAGE_POOL RxQ-0
[   47.954682] starfive-eth-plat 16040000.ethernet: Failed to reset the dma
[   47.961409] starfive-eth-plat 16040000.ethernet end1: stmmac_hw_setup: DMA engine initialization failed
[   47.970849] starfive-eth-plat 16040000.ethernet end1: stmmac_open: Hw setup failed

Using ethtool end1 has same outcome.

root@visionfive2-2:~# ethtool end1
netlink error: Device or resource busy
netlink error: Device or resource busy

[gopherbot]

Change https://go.dev/cl/586435 mentions this issue: unix: skip ethtool driver test for busy interface