ef4_fill_loopback_test(9)

✨ ef4_fill_loopback_test(9) ✨

okay so bestie, we're in the Kernel API Manual, section 9 today, and we're about to fill in some loopback self-test entries 💅 this is the falcon-era sfc ethtool-adjacent lore, and honestly? iconic.

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🎀 NAME 🎀

ef4_fill_loopback_test — fill in a block of loopback self-test entries 🦋

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🌸 SYNOPSIS 🌸

int ef4_fill_loopback_test (struct ef4_nic *efx , struct
       ef4_loopback_self_tests *lb_tests , enum ef4_loopback_mode mode ,
       unsigned int test_index , u8 *strings , u64 *data );

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💖 ARGUMENTS 💖

• efx — the Efx NIC, aka the actual network card we're doing all this for 👑
• lb_tests — the Efx loopback self-test results structure, where the results get written ✨
• mode — the loopback test mode, like which flavour of loopback we're vibing with 🌀
• test_index — the starting index of the test, so we know where in the block we're beginning 📍
• strings — ethtool strings, or NULL if you're not about that life 🙈
• data — ethtool test results, or NULL for the same reason 😌

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⭐ DESCRIPTION ⭐

Fill in a block of loopback self-test entries. Return the new test index 🔥

like, that's the whole gig. you hand it the block starting at test_index, it fills the entries in, and it hands you back the new test index so you know where things landed. no cap, that's it 🫶

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🦋 SEE ALSO 🦋

• Kernel file ./drivers/net/ethernet/sfc/falcon/ethtool.c 📁
• ef4_fill_test(9)
• ef4_ethtool_fill_self_tests(9)

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aaaaand that's the page, bestie 🧚 this one came straight out of ./drivers/net/ethernet/sfc/falcon, dated October 2026, and yeah — it's fr fr the ef4_fill_loopback_test(9) manual page, slay 💜 🌈 🍓