copy_mc_to_kernel(9)

🌸 copy_mc_to_kernel(9) 🌸

okay bestie, welcome to the Kernel API Manual, grab a strawberry 🍓 and let's talk about the memory copy that handles source exceptions — yes, that's the whole vibe of this page 💅

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✨ NAME ✨

copy_mc_to_kernel — a memory copy that handles source exceptions 🫶

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💖 SYNOPSIS 💖

unsigned long copy_mc_to_kernel (void *dst, const void *src, unsigned len );

like, that's the whole signature, no cap ✨

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🎀 ARGUMENTS 🎀

• dst — the destination address 💌
• src — the source address 🌟
• len — number of bytes to copy, literally the whole count 🔢

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🦋 DESCRIPTION 🦋

So here's the tea: this thing calls into the 'fragile' version on systems that benefit from avoiding corner case poison consumption scenarios 😭 for example, accessing poison across 2 cachelines with a single instruction — yeah, exactly that kind of cursed energy 💀

Almost all other uses case can use copy_mc_enhanced_fast_string for a fast recoverable copy, or fallback to plain memcpy 👑 iykyk.

It returns 0 for success, or the number of bytes not copied if there was an exception 🙈 so like, always check the return value bestie, fr fr.

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🌈 SEE ALSO 🌈

• Kernel file ./arch/x86/lib/copy_mc.c 📁

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okay that's the whole page, go forth and copy safely 🧚

this one came to you from ./arch/x86/lib, October 2026, and the page itself is copy_mc_to_kernel(9) — mwah, slay, periodt 💅💖