On 2021/6/22 7:25, Jason Gunthorpe wrote: > On Fri, Jun 11, 2021 at 05:35:56PM +0800, Weihang Li wrote: >> From: Jiaran Zhang <zhangjiaran@xxxxxxxxxx> >> >> During the reset, the driver calls dma_pool_destroy() to release the >> dma_pool resources. If the dma_pool_free interface is called during the >> modify_qp operation, an exception will occur. The completion >> synchronization mechanism is used to ensure that dma_pool_destroy() is >> executed after the dma_pool_free operation is complete. > > This should probably be a simple rwsem instead of faking one up with a > refcount and completion. > > The only time you need this pattern is if the code is returning to > userspace, which didn't look like was happening here. > > Jason > Thank you, we'll think about how to use rwsem to fix this. Weihang
