Hi Marc, On 8/20/21 9:47 AM, Marc Zyngier wrote: > Trying to boot without SYSFS, but with OF_DYNAMIC quickly > results in a crash: > > [ 0.088460] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000070 > [...] > [ 0.103927] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.14.0-rc3 #4179 > [ 0.105810] Hardware name: linux,dummy-virt (DT) > [ 0.107147] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO BTYPE=--) > [ 0.108876] pc : kernfs_find_and_get_ns+0x3c/0x7c > [ 0.110244] lr : kernfs_find_and_get_ns+0x3c/0x7c > [...] > [ 0.134087] Call trace: > [ 0.134800] kernfs_find_and_get_ns+0x3c/0x7c > [ 0.136054] safe_name+0x4c/0xd0 > [ 0.136994] __of_attach_node_sysfs+0xf8/0x124 > [ 0.138287] of_core_init+0x90/0xfc > [ 0.139296] driver_init+0x30/0x4c > [ 0.140283] kernel_init_freeable+0x160/0x1b8 > [ 0.141543] kernel_init+0x30/0x140 > [ 0.142561] ret_from_fork+0x10/0x18 > > While not having sysfs isn't a very common option these days, > it is still expected that such configuration would work. > > Paper over it by bailing out from __of_attach_node_sysfs() if > CONFIG_SYSFS isn't enabled. CONFIG_SYSFS should be automatically selected when CONFIG_OF_DYNAMIC is enabled, and it should not be possible to disable CONFIG_SYSFS in this case. Can you send your .config? What ARCH did you build the kernel with? Thanks, Frank > > Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> > --- > drivers/of/kobj.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/of/kobj.c b/drivers/of/kobj.c > index a32e60b024b8..6675b5e56960 100644 > --- a/drivers/of/kobj.c > +++ b/drivers/of/kobj.c > @@ -119,7 +119,7 @@ int __of_attach_node_sysfs(struct device_node *np) > struct property *pp; > int rc; > > - if (!of_kset) > + if (!IS_ENABLED(CONFIG_SYSFS) || !of_kset) > return 0; > > np->kobj.kset = of_kset; >
