6.15-stable review patch. If anyone has any objections, please let me know.
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From: Keith Busch kbusch@kernel.org
[ Upstream commit 5b2c214a95942f7997d1916a4c44017becbc3cac ]
NVMe devices from multiple vendors appear to get stuck in a reset state that we can't get out of with an NVMe level Controller Reset. The kernel would report these with messages that look like:
Device not ready; aborting reset, CSTS=0x1
These have historically required a power cycle to make them usable again, but in many cases, a PCIe FLR is sufficient to restart operation without a power cycle. Try it if the initial controller reset fails during any nvme reset attempt.
Signed-off-by: Keith Busch kbusch@kernel.org Reviewed-by: Chaitanya Kulkarni kch@nvidia.com Reviewed-by: Nitesh Shetty nj.shetty@samsung.com Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/host/pci.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-)
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 776c867fb64d..5396282015a2 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1888,8 +1888,28 @@ static int nvme_pci_configure_admin_queue(struct nvme_dev *dev) * might be pointing at! */ result = nvme_disable_ctrl(&dev->ctrl, false); - if (result < 0) - return result; + if (result < 0) { + struct pci_dev *pdev = to_pci_dev(dev->dev); + + /* + * The NVMe Controller Reset method did not get an expected + * CSTS.RDY transition, so something with the device appears to + * be stuck. Use the lower level and bigger hammer PCIe + * Function Level Reset to attempt restoring the device to its + * initial state, and try again. + */ + result = pcie_reset_flr(pdev, false); + if (result < 0) + return result; + + pci_restore_state(pdev); + result = nvme_disable_ctrl(&dev->ctrl, false); + if (result < 0) + return result; + + dev_info(dev->ctrl.device, + "controller reset completed after pcie flr\n"); + }
result = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH); if (result)