[PATCH] nvme: fix PCIe subsystem reset controller state transition

[Daniel Wagner]

On Wed, Jan 14, 2026 at 12:54:13PM +0530, Nilay Shroff wrote:
> 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 at vger.kernel.org
> Fixes: d2fe192348f9 ("nvme: only allow entering LIVE from CONNECTING state")
> Signed-off-by: Nilay Shroff <nilay at linux.ibm.com>

Thanks for fixing this.

Reviewed-by: Daniel Wagner <dwagner at suse.de>