linux-brain/arch/nios2
Tobias Klauser 1c47303355 nios2: reserve boot memory for device tree
commit 921d701e6f upstream.

Make sure to reserve the boot memory for the flattened device tree.
Otherwise it might get overwritten, e.g. when initial_boot_params is
copied, leading to a corrupted FDT and a boot hang/crash:

  bootconsole [early0] enabled
  Early console on uart16650 initialized at 0xf8001600
  OF: fdt: Error -11 processing FDT
  Kernel panic - not syncing: setup_cpuinfo: No CPU found in devicetree!

  ---[ end Kernel panic - not syncing: setup_cpuinfo: No CPU found in devicetree!

Guenter Roeck says:

> I think I found the problem. In unflatten_and_copy_device_tree(), with added
> debug information:
>
> OF: fdt: initial_boot_params=c861e400, dt=c861f000 size=28874 (0x70ca)
>
> ... and then initial_boot_params is copied to dt, which results in corrupted
> fdt since the memory overlaps. Looks like the initial_boot_params memory
> is not reserved and (re-)allocated by early_init_dt_alloc_memory_arch().

Reported-by: Guenter Roeck <linux@roeck-us.net>
Reference: http://lkml.kernel.org/r/20170226210338.GA19476@roeck-us.net
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Ley Foon Tan <ley.foon.tan@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:38:34 +02:00
..
boot nios2: Add Max10 device tree 2015-09-08 18:15:52 +08:00
configs nios2: add Max10 defconfig 2015-09-08 18:16:02 +08:00
include nios2: copy_from_user() should zero the tail of destination 2016-09-24 10:07:45 +02:00
kernel nios2: reserve boot memory for device tree 2017-04-12 12:38:34 +02:00
lib nios2: Remove unnecessary #ifdef guards 2015-11-09 10:33:30 +08:00
mm nios2: fix cache coherency 2015-11-26 22:25:58 +08:00
platform nios2: Build infrastructure 2014-12-08 12:56:06 +08:00
Kconfig nios2: add kgdb support 2015-02-16 19:26:43 +08:00
Kconfig.debug nios2: add early printk support 2015-02-10 23:21:08 +08:00
Makefile nios2: enable "make defconfig" 2014-12-17 13:37:09 +08:00