Rob Herring <r...@kernel.org> writes: > On Fri, Sep 15, 2017 at 6:04 AM, abdul <abdha...@linux.vnet.ibm.com> wrote: >> Hi, >> >> Mainline kernel panics during DLPAR CPU add/remove operation. >> >> Machine Type: Power8 PowerVM LPAR >> kernel 4.13.0 > > Did 4.12 work or when was it last working? I'm not seeing anything > recent in the DT code that looks suspicious.
I'm pretty sure it's: int dlpar_attach_node(struct device_node *dn, struct device_node *parent) { int rc; dn->parent = parent; rc = of_attach_node(dn); if (rc) { printk(KERN_ERR "Failed to add device node %pOF\n", dn); return rc; } of_node_put(dn->parent); HERE ^^^^^^^^^^ return 0; } Prior to 215ee763f8cb ("powerpc: pseries: remove dlpar_attach_node dependency on full path"), we re-looked up the parent, and got another reference on it. That meant the put before the return there was correct. But now it's not because the caller has a reference to parent but it's not ours to drop. Testing a fix, will report back. cheers