From: Keith Busch <keith.busch@xxxxxxxxx> [ Upstream commit 9fe5c59ff6a1e5e26a39b75489a1420e7eaaf0b1 ] The nvme pci driver had been adding its CMB resource to the P2P DMA subsystem everytime on on a controller reset. This results in the following warning: ------------[ cut here ]------------ nvme 0000:00:03.0: Conflicting mapping in same section WARNING: CPU: 7 PID: 81 at kernel/memremap.c:155 devm_memremap_pages+0xa6/0x380 ... Call Trace: pci_p2pdma_add_resource+0x153/0x370 nvme_reset_work+0x28c/0x17b1 [nvme] ? add_timer+0x107/0x1e0 ? dequeue_entity+0x81/0x660 ? dequeue_entity+0x3b0/0x660 ? pick_next_task_fair+0xaf/0x610 ? __switch_to+0xbc/0x410 process_one_work+0x1cf/0x350 worker_thread+0x215/0x3d0 ? process_one_work+0x350/0x350 kthread+0x107/0x120 ? kthread_park+0x80/0x80 ret_from_fork+0x1f/0x30 ---[ end trace f7ea76ac6ee72727 ]--- nvme nvme0: failed to register the CMB This patch fixes this by registering the CMB with P2P only once. Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx> Reviewed-by: Logan Gunthorpe <logang@xxxxxxxxxxxx> Signed-off-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/nvme/host/pci.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index e10b0d20c4a7..113e5c786231 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1718,6 +1718,9 @@ static void nvme_map_cmb(struct nvme_dev *dev) struct pci_dev *pdev = to_pci_dev(dev->dev); int bar; + if (dev->cmb_size) + return; + dev->cmbsz = readl(dev->bar + NVME_REG_CMBSZ); if (!dev->cmbsz) return; @@ -2200,7 +2203,6 @@ static void nvme_pci_disable(struct nvme_dev *dev) { struct pci_dev *pdev = to_pci_dev(dev->dev); - nvme_release_cmb(dev); pci_free_irq_vectors(pdev); if (pci_is_enabled(pdev)) { @@ -2648,6 +2650,7 @@ static void nvme_remove(struct pci_dev *pdev) nvme_stop_ctrl(&dev->ctrl); nvme_remove_namespaces(&dev->ctrl); nvme_dev_disable(dev, true); + nvme_release_cmb(dev); nvme_free_host_mem(dev); nvme_dev_remove_admin(dev); nvme_free_queues(dev, 0); -- 2.17.1