linux_dsm_epyc7002/arch/nios2/kernel/prom.c
Tobias Klauser 921d701e6f nios2: reserve boot memory for device tree
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().

Cc: stable@vger.kernel.org
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>
2017-04-02 20:13:57 -07:00

122 lines
2.9 KiB
C

/*
* Device tree support
*
* Copyright (C) 2013, 2015 Altera Corporation
* Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
*
* Based on MIPS support for CONFIG_OF device tree support
*
* Copyright (C) 2010 Cisco Systems Inc. <dediao@cisco.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <linux/init.h>
#include <linux/types.h>
#include <linux/bootmem.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/io.h>
#include <asm/prom.h>
#include <asm/sections.h>
void __init early_init_dt_add_memory_arch(u64 base, u64 size)
{
u64 kernel_start = (u64)virt_to_phys(_text);
if (!memory_size &&
(kernel_start >= base) && (kernel_start < (base + size)))
memory_size = size;
}
void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
{
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;
#if defined(CONFIG_NIOS2_DTB_AT_PHYS_ADDR)
if (be32_to_cpup((__be32 *)CONFIG_NIOS2_DTB_PHYS_ADDR) ==
OF_DT_HEADER) {
params = (void *)CONFIG_NIOS2_DTB_PHYS_ADDR;
early_init_dt_scan(params);
return;
}
#endif
if (be32_to_cpu((__be32) *dtb) == OF_DT_HEADER)
params = (void *)__dtb_start;
early_init_dt_scan(params);
}
#ifdef CONFIG_EARLY_PRINTK
static int __init early_init_dt_scan_serial(unsigned long node,
const char *uname, int depth, void *data)
{
u64 *addr64 = (u64 *) data;
const char *p;
/* only consider serial nodes */
if (strncmp(uname, "serial", 6) != 0)
return 0;
p = of_get_flat_dt_prop(node, "compatible", NULL);
if (!p)
return 0;
/*
* We found an altera_jtaguart but it wasn't configured for console, so
* skip it.
*/
#ifndef CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE
if (strncmp(p, "altr,juart", 10) == 0)
return 0;
#endif
/*
* Same for altera_uart.
*/
#ifndef CONFIG_SERIAL_ALTERA_UART_CONSOLE
if (strncmp(p, "altr,uart", 9) == 0)
return 0;
#endif
*addr64 = of_flat_dt_translate_address(node);
return *addr64 == OF_BAD_ADDR ? 0 : 1;
}
unsigned long __init of_early_console(void)
{
u64 base = 0;
if (of_scan_flat_dt(early_init_dt_scan_serial, &base))
return (u32)ioremap(base, 32);
else
return 0;
}
#endif /* CONFIG_EARLY_PRINTK */