Frank Rowand <frowand.list@xxxxxxxxx> writes: > On 12/11/18 8:07 AM, Rob Herring wrote: >> On Tue, Dec 11, 2018 at 7:29 AM Michael Ellerman <mpe@xxxxxxxxxxxxxx> wrote: ... >>> diff --git a/drivers/of/base.c b/drivers/of/base.c >>> index 09692c9b32a7..d8e4534c0686 100644 >>> --- a/drivers/of/base.c >>> +++ b/drivers/of/base.c >>> @@ -1190,6 +1190,10 @@ struct device_node *of_find_node_by_phandle(phandle handle) >>> if (phandle_cache[masked_handle] && >>> handle == phandle_cache[masked_handle]->phandle) >>> np = phandle_cache[masked_handle]; >>> + >>> + /* If we find a detached node, remove it */ >>> + if (of_node_check_flag(np, OF_DETACHED)) >>> + np = phandle_cache[masked_handle] = NULL; > > The bug you found exposes a couple of different issues, a little bit > deeper than the proposed fix. I'll work on a fuller fix tonight or > tomorrow. OK thanks. >> I'm wondering if we should explicitly remove the node from the cache >> when we set OF_DETACHED. Otherwise, it could be possible that the node >> pointer has been freed already. Or maybe we need both? > > Yes, it should be explicitly removed. I may also add in a paranoia check in > of_find_node_by_phandle(). That seems best to me. cheers
