From: Marc Zyngier maz@kernel.org
stable inclusion from linux-4.19.207 commit 3f3c58973177a70c9b94a3ce85375529d3cb5b3c
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[ Upstream commit 6211e9cb2f8faf7faae0b6caf844bfe9527cc607 ]
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.
Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20210820144722.169226-1-maz@kernel.org Signed-off-by: Rob Herring robh@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- 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 a32e60b024b8d..6675b5e56960c 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;