__kcsan_check_write(9)

💅 __kcsan_check_write — check regular write access for races

okay so first things first, bestie: this lil guy lives in the Kernel API Manual, section 9, and its government name is __kcsan_check_write. Say it with me — it's the "hey KCSAN, I'm about to write something, pls watch for races" check 🎀

---

✨ NAME ✨

__kcsan_check_write — check regular write access for races 🌸

Like, it's giving "tell the race detector that a plain ol' regular write is happening at this address, with this size." No cap, that's the whole job. 💖

---

🦋 SYNOPSIS 🦋

__kcsan_check_write (ptr , size );

yep that's it, that's the icon. two arguments, spaced all cute like the original, copy-paste it exactly and you're golden ✨

---

👑 ARGUMENTS 👑

• ptr — address of access 📍 like, where the write is happening, babe.
• size — size of access 📏 how many bytes we're writing. be honest about this one fr fr.

---

🌈 SEE ALSO 🌈

okay this is the part where the manpage just. keeps. going. 💀 but every single one of these is part of the family so we're listing them ALL, no skipping, periodt:

• Kernel file ./include/linux/kcsan-checks.h 📁
• __kcsan_check_access(9)
• __kcsan_mb(9)
• __kcsan_wmb(9)
• __kcsan_rmb(9)
• __kcsan_release(9)
• kcsan_disable_current(9)
• kcsan_enable_current(9)
• kcsan_nestable_atomic_begin(9)
• kcsan_nestable_atomic_end(9)
• kcsan_flat_atomic_begin(9)
• kcsan_flat_atomic_end(9)
• kcsan_atomic_next(9)
• kcsan_set_access_mask(9)
• kcsan_begin_scoped_access(9)
• kcsan_end_scoped_access(9)
• __kcsan_check_read(9)
• __kcsan_check_read_write(9)
• kcsan_check_read(9)
• kcsan_check_write(9)
• kcsan_check_read_write(9)
• ASSERT_EXCLUSIVE_WRITER(9)
• ASSERT_EXCLUSIVE_WRITER_SCOPED(9)
• ASSERT_EXCLUSIVE_ACCESS(9)
• ASSERT_EXCLUSIVE_ACCESS_SCOPED(9)
• ASSERT_EXCLUSIVE_BITS(9)

like, go read them, they're all lowkey iconic in their own way 🫶

---

ngl the whole KCSAN crew is a vibe — this one's just the "regular write" member of the squad, so hit up the others when you need reads, atomics, scoped access, or the ASSERT_EXCLUSIVE_* besties 💜

---

kay that's the whole page, mwah 💋 — this came straight out of ./include/linux, dated October 2026, and the header/footer literally just repeat __kcsan_check_write(9) at you because the manpage format is dramatic like that. slay. 💅✨