Fix two device-unregistration lifecycle bugs in devmem TCP bindings and add netdevsim support plus selftests covering both RX and TX device unregistration:
1. net: devmem: unmap dma_buf synchronously on queue uninstall Synchronously unmap and detach binding->attachment under binding->lock when the last RX queue is uninstalled in mp_dmabuf_devmem_uninstall(), and unmap RX bindings that were already unbound on NETDEV_UNREGISTER, preventing slab-use-after-free in dma_unmap_sg_attrs() when the binding is freed after dma_dev. 2. net: devmem: detach TX bindings on NETDEV_UNREGISTER Extend net_devmem_dev_unregister() to fully detach and unmap TX bindings when binding->dev unregisters, or clear binding->vdev alone when only a virtual device unregisters while binding->dev lives. 3. netdevsim: support devmem RX and TX bindings Enable PP_FLAG_DMA_MAP | PP_FLAG_ALLOW_UNREADABLE_NETMEM, 64-bit DMA mask on nsim_bus_dev, and NETMEM_TX_DMA on netdevsim so devmem RX/TX bindings can be exercised in software selftests. 4. selftests: net: add devmem RX and TX netdev unregister tests Add devmem_bind_rx_unregister_check and devmem_bind_tx_unregister_check to tools/testing/selftests/net/nl_netdev.py. Cc: Tariq Toukan <[email protected]> Cc: Kaifeng Wang <[email protected]> --- v2: - 1/4: Don't unmap when a leased queue is unleased. Keep bindings in net_devmem_dmabuf_bindings until freed, hidden from TX lookups by an xarray mark, and unmap unbound RX bindings on NETDEV_UNREGISTER. Update the binding->lock and binding->ref comments. (Sashiko) - 2/4: Detach TX bindings from the same net_devmem_lock-protected walk, which now also covers unbound TX bindings, and clear the LIVE mark instead of erasing the ID. The walk no longer uses RCU or takes binding references (Stanislav). - Link to v1: https://lore.kernel.org/netdev/[email protected]/ Mina Almasry (4): net: devmem: unmap dma_buf synchronously on queue uninstall net: devmem: detach TX bindings on NETDEV_UNREGISTER netdevsim: support devmem RX and TX bindings selftests: net: add devmem RX and TX netdev unregister tests drivers/net/netdevsim/bus.c | 1 + drivers/net/netdevsim/netdev.c | 21 ++-- net/core/devmem.c | 121 ++++++++++++++++++++--- net/core/devmem.h | 10 +- net/core/netdev-genl.c | 1 + tools/testing/selftests/net/nl_netdev.py | 108 +++++++++++++++++++- 6 files changed, 236 insertions(+), 26 deletions(-) base-commit: 4f6ac74fa594a918d41255c941256e1d51592d3b -- 2.56.0.385.gd3acb90ef8-goog
