From 1e9ced28f18ed75bef96df08e47baad27dd51829 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Sun, 1 Aug 2021 12:05:23 -0600 Subject: dm: core: Don't allow uclass use before ready At present it is possible to call uclass_get() before driver model is inited. In fact this happens on x86 boards which use Intel FSPv1, since mrccache_get_region() tries to get the SPI flash device very early during init. This has always been undefined behaviour. Previously it generally worked, i.e. returned an error code without crashing, because gd->uclass_root_s is zeroed and the uclass can be added despite driver model not being ready, due to the way lists are implemented. With the change to use a gd->uclass_root pointer, this no-longer works. For example, it causes a hang on minnowmax. Fix this by adding a check that driver model is ready when uclass_get() is called. This function is called in the process of locating any device, so it is a good place to add the check. This fixes booting on minnowmax. Signed-off-by: Simon Glass Fixes: 8a715530bb1 ("dm: core: Allow the uclass list to move") --- drivers/core/uclass.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/core') diff --git a/drivers/core/uclass.c b/drivers/core/uclass.c index 117d35ac49..3146dfd032 100644 --- a/drivers/core/uclass.c +++ b/drivers/core/uclass.c @@ -146,6 +146,9 @@ int uclass_get(enum uclass_id id, struct uclass **ucp) { struct uclass *uc; + /* Immediately fail if driver model is not set up */ + if (!gd->uclass_root) + return -EDEADLK; *ucp = NULL; uc = uclass_find(id); if (!uc) { -- cgit v1.2.3