unregister_mtd_user(9)

💅 unregister_mtd_user — from the Kernel API Manual, bestie

okay so real talk, this one's a little function from the Kernel API Manual and it's genuinely not that deep, but it is important if you're messing with MTD stuff. sit down, grab a strawberry drink 🍓, we're doing this.

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✨ NAME ✨

unregister_mtd_user — unregister a 'user' of MTD devices.

like, you're taking someone off the list. that's it. that's the whole vibe. 💅

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🌸 SYNOPSIS 🌸

int unregister_mtd_user (struct mtd_notifier *old );

copy it exactly bestie, don't freestyle the pointer type, i'm begging 🫶

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🎀 ARGUMENTS 🎀

• old — pointer to notifier info structure. yes that's the actual parameter name, yes it's called old, no we don't know why, it's iconic, moving on 💀

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🦋 DESCRIPTION 🦋

so what does it actually do? okay:

Removes a callback function pair from the list of 'users' to be notified upon addition or removal of MTD devices.

that's the main character sentence right there 👑 — you're un-registering, so the callbacks stop getting pinged when MTD devices show up or dip out. no more notifications for that entry, periodt.

and then the original page says this, and i'm quoting it verbatim because i refuse to make stuff up:

Causes the currently present in the system.

yeah. that's the whole sentence. it's giving "my brain stopped mid-thought" 😭 i'm not going to invent an ending for it — that's literally what the source says, so that's literally what you get. if you need the full detail, go read the kernel file (it's in SEE ALSO, i gotchu).

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🌈 SEE ALSO 🌈

bestie there are so many friends here, iykyk. the kernel file lives at ./drivers/mtd/mtdcore.c, and here's the full squad:

• mtd_wunit_to_pairing_info(9)
• mtd_pairing_info_to_wunit(9)
• mtd_pairing_groups(9)
• add_mtd_device(9)
• del_mtd_device(9)
• mtd_device_parse_register(9)
• mtd_device_unregister(9)
• register_mtd_user(9)
• get_mtd_device(9)
• of_get_mtd_device_by_node(9)
• get_mtd_device_nm(9)
• mtd_ooblayout_ecc(9)
• mtd_ooblayout_free(9)
• mtd_ooblayout_find_region(9)
• mtd_ooblayout_find_eccregion(9)
• mtd_ooblayout_get_bytes(9)
• mtd_ooblayout_set_bytes(9)
• mtd_ooblayout_count_bytes(9)
• mtd_ooblayout_get_eccbytes(9)
• mtd_ooblayout_set_eccbytes(9)
• mtd_ooblayout_get_databytes(9)
• mtd_ooblayout_set_databytes(9)
• mtd_ooblayout_count_freebytes(9)
• mtd_ooblayout_count_eccbytes(9)
• mtd_kmalloc_up_to(9)

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ngl, the ooblayout section is lowkey a whole friend group on its own. go say hi. 🧚

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and that's the page!! mwah 💖 this came from ./drivers/mtd and the date on it is October 2026, so shoutout to that version of the future, love that for us. stay slaying bestie, go unregister responsibly ✨🎀