Patch "nios2: reserve boot memory for device tree" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

nios2: reserve boot memory for device tree

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
nios2-reserve-boot-memory-for-device-tree.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Tobias Klauser <[email protected]>
Date: Sun, 2 Apr 2017 20:08:04 -0700
Subject: nios2: reserve boot memory for device tree

From: Tobias Klauser <[email protected]>

commit 921d701e6f31e1ffaca3560416af1aa04edb4c4f 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:

Reference: http://lkml.kernel.org/r/[email protected]

---
 arch/nios2/kernel/prom.c  |    7 +++++++
 arch/nios2/kernel/setup.c |    3 +++
 2 files changed, 10 insertions(+)

@@ -48,6 +48,13 @@ void * __init early_init_dt_alloc_memory
 	return alloc_bootmem_align(size, align);
 }
 
+int __init early_init_dt_reserve_memory_arch(phys_addr_t base, phys_addr_t size,
+					     bool nomap)
+{
+	reserve_bootmem(base, size, BOOTMEM_DEFAULT);
+	return 0;
+}
+
 void __init early_init_devtree(void *params)
 {
 	__be32 *dtb = (u32 *)__dtb_start;

@@ -195,6 +195,9 @@ void __init setup_arch(char **cmdline_p)
 	}
 #endif /* CONFIG_BLK_DEV_INITRD */
 
+	early_init_fdt_reserve_self();
+	early_init_fdt_scan_reserved_mem();
+
 	unflatten_and_copy_device_tree();
 
 	setup_cpuinfo();

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/nios2-reserve-boot-memory-for-device-tree.patch