From: Nilay Shroff Date: Wed, 14 Jan 2026 07:24:13 +0000 (+0530) Subject: nvme: fix PCIe subsystem reset controller state transition X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0edb475ac0a7d153318a24d4dca175a270a5cc4f;p=thirdparty%2Flinux.git nvme: fix PCIe subsystem reset controller state transition The commit d2fe192348f9 (“nvme: only allow entering LIVE from CONNECTING state”) disallows controller state transitions directly from RESETTING to LIVE. However, the NVMe PCIe subsystem reset path relies on this transition to recover the controller on PowerPC (PPC) systems. On PPC systems, issuing a subsystem reset causes a temporary loss of communication with the NVMe adapter. A subsequent PCIe MMIO read then triggers EEH recovery, which restores the PCIe link and brings the controller back online. For EEH recovery to proceed correctly, the controller must transition back to the LIVE state. Due to the changes introduced by commit d2fe192348f9 (“nvme: only allow entering LIVE from CONNECTING state”), the controller can no longer transition directly from RESETTING to LIVE. As a result, EEH recovery exits prematurely, leaving the controller stuck in the RESETTING state. Fix this by explicitly transitioning the controller state from RESETTING to CONNECTING and then to LIVE. This satisfies the updated state transition rules and allows the controller to be successfully recovered on PPC systems following a PCIe subsystem reset. Cc: stable@vger.kernel.org Fixes: d2fe192348f9 ("nvme: only allow entering LIVE from CONNECTING state") Reviewed-by: Daniel Wagner Signed-off-by: Nilay Shroff Signed-off-by: Keith Busch --- diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 29e715d5b8f3..58f3097888a7 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1532,7 +1532,10 @@ static int nvme_pci_subsystem_reset(struct nvme_ctrl *ctrl) } writel(NVME_SUBSYS_RESET, dev->bar + NVME_REG_NSSR); - nvme_change_ctrl_state(ctrl, NVME_CTRL_LIVE); + + if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_CONNECTING) || + !nvme_change_ctrl_state(ctrl, NVME_CTRL_LIVE)) + goto unlock; /* * Read controller status to flush the previous write and trigger a