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uaz4gDFB4B/hQwVfl65eV9dIoiRFTwWDRndyuvCtMzNfScB9/hFPTpclY9uGvmYncqjfBmLotab jTuPEEAmZyrdpCJB/3dBJos5PnsUtQj6cjTwIaOG04Ck1KdQlyuipH3NpGF4ZJPbg3pyMLSrUOy bOdVOprzyrbMs2wDL7pC9WgdD2d2eaY2RAzK59Idaqe5Kgk2DCw1gEerAeOx1a9frWswBJoKYMA gUdaVedYTN2EshqWrefRBOKBNwyR/SfN9TcEi0m/XwrBK29UodpLEyC2cCxMQ2NZtXYxomRR X-Proofpoint-GUID: 2hDzerFUfVxfsNptVaMUCYO89OgSD-C9 X-Authority-Analysis: v=2.4 cv=IsYecK/g c=1 sm=1 tr=0 ts=6881c38e b=1 cx=c_pps a=e1sVV491RgrpLwSTMOnk8w==:117 a=e1sVV491RgrpLwSTMOnk8w==:17 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=wKuvFiaSGQ0qltdbU6+NXLB8nM8=:19 a=Ol13hO9ccFRV9qXi2t6ftBPywas=:19 a=xqWC_Br6kY4A:10 a=IkcTkHD0fZMA:10 a=Wb1JkmetP80A:10 a=GoEa3M9JfhUA:10 a=1XWaLZrsAAAA:8 a=56QpafP7TFTAxLFPCxcA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 cc=ntf awl=host:13600 X-Proofpoint-ORIG-GUID: 2hDzerFUfVxfsNptVaMUCYO89OgSD-C9 On Wed, Jul 23, 2025 at 10:00:40PM +0200, Jann Horn wrote: > On Wed, Jul 23, 2025 at 9:52 PM Jann Horn wrote: > > I'm not sure if I'm understanding you correctly; but yes, > > __vma_enter_locked() waits for all the waiters to drop their > > "refcounts". (It's not really a refcount, you can also think of it as > > a sleepable read-write lock where the low bits are the number of > > readers.) > > Sorry, that's not entirely true, since an attached VMA has a refcount > elevated by one. It's kind of a refcount, and kind of forms part of a > sleepable read-write lock, it's complicated. And needs internal impl detail documentation IMO. Which I'll provide...