From b5b532cca13db3744103d8c7e5ee2deac5c72609 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Mon, 6 Jun 2022 09:53:17 -0700 Subject: [PATCH] nvme-pci: add trouble shooting steps for timeouts Many users have encountered IO timeouts with a CSTS value of 0xffffffff, which indicates a failure to read the register. While there are various potential causes for this observation, faulty NVMe APST has been the culprit quite frequently. Add the recommended troubleshooting steps in the error output when this condition occurs. Signed-off-by: Keith Busch Reviewed-by: Chaitanya Kulkarni Signed-off-by: Christoph Hellwig --- drivers/nvme/host/pci.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 96579d48002a1..be053d943731b 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1334,6 +1334,14 @@ static void nvme_warn_reset(struct nvme_dev *dev, u32 csts) dev_warn(dev->ctrl.device, "controller is down; will reset: CSTS=0x%x, PCI_STATUS read failed (%d)\n", csts, result); + + if (csts != ~0) + return; + + dev_warn(dev->ctrl.device, + "Does your device have a faulty power saving mode enabled?\n"); + dev_warn(dev->ctrl.device, + "Try \"nvme_core.default_ps_max_latency_us=0 pcie_aspm=off\" and report a bug\n"); } static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved) -- 2.39.5