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X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sat, Sep 06, 2025 at 12:45:58AM -0700, Nicolin Chen wrote: > One thing that I noticed is that group mutex alone isn't enough, > because there can be two arm_smmu_build_invs() calls during the > same attach_dev callback. And the second one would overwrite. Well the group mutex is what makes it non-concurrent. Two things using it sequentially within the same thread are a different issue Jason