My Jetson TX2 freshly installed with Jetpack 3.0 immediately crashes and reboots whenever the dmidecode utility is run.
I have also verified the problem is not fixed by installing the latest Ubuntu updates.
The dmidecode utility is invoked by various hardware-discovery scripts that we run. Note that on the TX1 the utility produced this output:
root@jetson-tx1:~# dmidecode
dmidecode 3.0
Scanning /dev/mem for entry point.
No SMBIOS nor DMI entry point found, sorry.
root@jetson-tx1:~#
Bibek
April 14, 2017, 2:50am
3
“dmidecode” command is trying to read from address “0xf0000” using “/dev/mem” node. “drivers/char/mem.c” does mmap() on address from userspace and causes SError on accessing this address.
It needs to be fixed in the application.
sumitg
April 17, 2017, 6:13am
4
Below workaround patch can be applied to avoid the kernel crash.
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 6b1721f…10fe2bb 100644
— a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -80,6 +80,16 @@ static inline int range_is_allowed(unsigned long pfn, unsigned long size)
#else
static inline int range_is_allowed(unsigned long pfn, unsigned long size)
{
+#ifdef CONFIG_ARCH_OR_PLATFORM_TEGRA
//Not allow read/write requests for first 2MB and PFN Invalid
if((!pfn_valid(pfn)) && (pfn <= 0x200))
{
printk(KERN_INFO "Program %s tried to access /dev/mem between %lx->%lx.\n",
current->comm, (pfn << PAGE_SHIFT), ((pfn<<PAGE_SHIFT)+size));
return 0;
}
else
+#endif
return 1;
}
#endif