On 2018-11-26 3:49 a.m., Greg Kroah-Hartman wrote:
4.19-stable review patch. If anyone has any objections, please let me know.
This commit is fixing a bug in the p2pdma code which was merged for 4.20. I'm not sure it would actually fix anything in the stable kernels. On the other hand, based on my understanding, it shouldn't hurt anything either.
Thanks,
Logan
[ 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 CMBThis patch fixes this by registering the CMB with P2P only once.
Signed-off-by: Keith Busch keith.busch@intel.com Reviewed-by: Logan Gunthorpe logang@deltatee.com Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org
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 d668682f91df..da18e0ac9fa2 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1647,6 +1647,9 @@ 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;
@@ -2129,7 +2132,6 @@ 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)) { @@ -2577,6 +2579,7 @@ 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);