Hi Sachin,
On Thu, Jun 30, 2022 at 05:01:57PM +0530, Sachin Sant wrote:
> [ 0.000478] kobject: '(null)' ((____ptrval____)): is not initialized, yet kobject_get() is being called.
> [ 0.002925] [c000000002a0fb30] [c00000000073b0bc] kobject_get+0x8c/0x100 (unreliable)
> [ 0.003071] [c000000002a0fba0] [c00000000087e464] device_add+0xf4/0xb00
> [ 0.003194] [c000000002a0fc80] [c000000000a7f6e4] of_device_add+0x64/0x80
> [ 0.003321] [c000000002a0fcb0] [c000000000a800d0] of_platform_device_create_pdata+0xd0/0x1b0
> [ 0.003476] [c000000002a0fd00] [c00000000201fa44] pnv_get_random_long_early+0x240/0x2e4
> [ 0.003623] [c000000002a0fe20] [c000000002060c38] random_init+0xc0/0x214
Huh, that's a surprise, because random_init() is being called long after
all of the arch-specific stuff is initialized. This might point to
something else fishy happening during ppc's init? Or maybe the of device
needs a parent that hasn't been initialized yet. Not sure... But see if
the below patch fixes the issue. I don't have a POWER8 machine to try
this on, but if it works for you, I'll build it into a real patch.
Jason
diff --git a/arch/powerpc/platforms/powernv/rng.c b/arch/powerpc/platforms/powernv/rng.c
index 463c78c52cc5..bd5ad5f351c2 100644
--- a/arch/powerpc/platforms/powernv/rng.c
+++ b/arch/powerpc/platforms/powernv/rng.c
@@ -176,12 +176,8 @@ static int __init pnv_get_random_long_early(unsigned long *v)
NULL) != pnv_get_random_long_early)
return 0;
- for_each_compatible_node(dn, NULL, "ibm,power-rng") {
- if (rng_create(dn))
- continue;
- /* Create devices for hwrng driver */
- of_platform_device_create(dn, NULL, NULL);
- }
+ for_each_compatible_node(dn, NULL, "ibm,power-rng")
+ rng_create(dn);
if (!ppc_md.get_random_seed)
return 0;
@@ -205,10 +201,16 @@ void __init pnv_rng_init(void)
static int __init pnv_rng_late_init(void)
{
+ struct device_node *dn;
unsigned long v;
+
/* In case it wasn't called during init for some other reason. */
if (ppc_md.get_random_seed == pnv_get_random_long_early)
pnv_get_random_long_early(&v);
+ if (ppc_md.get_random_seed == powernv_get_random_long) {
+ for_each_compatible_node(dn, NULL, "ibm,power-rng")
+ of_platform_device_create(dn, NULL, NULL);
+ }
return 0;
}
machine_subsys_initcall(powernv, pnv_rng_late_init);
