Re: [RFC] Potential problem in qspinlock due to mixed-size accesses
Thomas Haas <[email protected]> Wed, 17 Dec 2025 20:05:23 +0100
| Newsgroups | dev.linux.lists.lkmm,org.kernel.vger.linux-arch,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
On 12.06.25 16:55, Thomas Haas wrote: > We have been taking a look if mixed-size accesses (MSA) can affect the > correctness of qspinlock. > We are focusing on aarch64 which is the only memory model with MSA > support [1]. > For this we extended the dartagnan [2] tool to support MSA and now it > reports liveness, synchronization, and mutex issues. --- cut off --- ARM has recently fixed the issue on their side by strengthening the memory model (see https://github.com/herd/herdtools7/commit/2b7921a44a61766e23a1234767d28af696b436a0) With the updated ARM-MSA model, Dartagnan does no longer find violations in qspinlock. No patches needed :) With best regards, Thomas