Files
android_kernel_xiaomi_sm8450/arch/riscv/kernel/setup.c
Conor Dooley 94ab8f88fe riscv: fix reserved memory setup
[ Upstream commit 50e63dd8ed92045eb70a72d7ec725488320fb68b ]

Currently, RISC-V sets up reserved memory using the "early" copy of the
device tree. As a result, when trying to get a reserved memory region
using of_reserved_mem_lookup(), the pointer to reserved memory regions
is using the early, pre-virtual-memory address which causes a kernel
panic when trying to use the buffer's name:

 Unable to handle kernel paging request at virtual address 00000000401c31ac
 Oops [#1]
 Modules linked in:
 CPU: 0 PID: 0 Comm: swapper Not tainted 6.0.0-rc1-00001-g0d9d6953d834 #1
 Hardware name: Microchip PolarFire-SoC Icicle Kit (DT)
 epc : string+0x4a/0xea
  ra : vsnprintf+0x1e4/0x336
 epc : ffffffff80335ea0 ra : ffffffff80338936 sp : ffffffff81203be0
  gp : ffffffff812e0a98 tp : ffffffff8120de40 t0 : 0000000000000000
  t1 : ffffffff81203e28 t2 : 7265736572203a46 s0 : ffffffff81203c20
  s1 : ffffffff81203e28 a0 : ffffffff81203d22 a1 : 0000000000000000
  a2 : ffffffff81203d08 a3 : 0000000081203d21 a4 : ffffffffffffffff
  a5 : 00000000401c31ac a6 : ffff0a00ffffff04 a7 : ffffffffffffffff
  s2 : ffffffff81203d08 s3 : ffffffff81203d00 s4 : 0000000000000008
  s5 : ffffffff000000ff s6 : 0000000000ffffff s7 : 00000000ffffff00
  s8 : ffffffff80d9821a s9 : ffffffff81203d22 s10: 0000000000000002
  s11: ffffffff80d9821c t3 : ffffffff812f3617 t4 : ffffffff812f3617
  t5 : ffffffff812f3618 t6 : ffffffff81203d08
 status: 0000000200000100 badaddr: 00000000401c31ac cause: 000000000000000d
 [<ffffffff80338936>] vsnprintf+0x1e4/0x336
 [<ffffffff80055ae2>] vprintk_store+0xf6/0x344
 [<ffffffff80055d86>] vprintk_emit+0x56/0x192
 [<ffffffff80055ed8>] vprintk_default+0x16/0x1e
 [<ffffffff800563d2>] vprintk+0x72/0x80
 [<ffffffff806813b2>] _printk+0x36/0x50
 [<ffffffff8068af48>] print_reserved_mem+0x1c/0x24
 [<ffffffff808057ec>] paging_init+0x528/0x5bc
 [<ffffffff808031ae>] setup_arch+0xd0/0x592
 [<ffffffff8080070e>] start_kernel+0x82/0x73c

early_init_fdt_scan_reserved_mem() takes no arguments as it operates on
initial_boot_params, which is populated by early_init_dt_verify(). On
RISC-V, early_init_dt_verify() is called twice. Once, directly, in
setup_arch() if CONFIG_BUILTIN_DTB is not enabled and once indirectly,
very early in the boot process, by parse_dtb() when it calls
early_init_dt_scan_nodes().

This first call uses dtb_early_va to set initial_boot_params, which is
not usable later in the boot process when
early_init_fdt_scan_reserved_mem() is called. On arm64 for example, the
corresponding call to early_init_dt_scan_nodes() uses fixmap addresses
and doesn't suffer the same fate.

Move early_init_fdt_scan_reserved_mem() further along the boot sequence,
after the direct call to early_init_dt_verify() in setup_arch() so that
the names use the correct virtual memory addresses. The above supposed
that CONFIG_BUILTIN_DTB was not set, but should work equally in the case
where it is - unflatted_and_copy_device_tree() also updates
initial_boot_params.

Reported-by: Valentina Fernandez <valentina.fernandezalanis@microchip.com>
Reported-by: Evgenii Shatokhin <e.shatokhin@yadro.com>
Link: https://lore.kernel.org/linux-riscv/f8e67f82-103d-156c-deb0-d6d6e2756f5e@microchip.com/
Fixes: 922b0375fc ("riscv: Fix memblock reservation for device tree blob")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Evgenii Shatokhin <e.shatokhin@yadro.com>
Link: https://lore.kernel.org/r/20221107151524.3941467-1-conor.dooley@microchip.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-16 09:57:14 +01:00

135 lines
2.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
* Chen Liqin <liqin.chen@sunplusct.com>
* Lennox Wu <lennox.wu@sunplusct.com>
* Copyright (C) 2012 Regents of the University of California
*/
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/memblock.h>
#include <linux/sched.h>
#include <linux/console.h>
#include <linux/screen_info.h>
#include <linux/of_fdt.h>
#include <linux/of_platform.h>
#include <linux/sched/task.h>
#include <linux/swiotlb.h>
#include <linux/smp.h>
#include <linux/efi.h>
#include <asm/cpu_ops.h>
#include <asm/early_ioremap.h>
#include <asm/setup.h>
#include <asm/sections.h>
#include <asm/sbi.h>
#include <asm/tlbflush.h>
#include <asm/thread_info.h>
#include <asm/kasan.h>
#include <asm/efi.h>
#include "head.h"
#if defined(CONFIG_DUMMY_CONSOLE) || defined(CONFIG_EFI)
struct screen_info screen_info __section(".data") = {
.orig_video_lines = 30,
.orig_video_cols = 80,
.orig_video_mode = 0,
.orig_video_ega_bx = 0,
.orig_video_isVGA = 1,
.orig_video_points = 8
};
#endif
/*
* The lucky hart to first increment this variable will boot the other cores.
* This is used before the kernel initializes the BSS so it can't be in the
* BSS.
*/
atomic_t hart_lottery __section(".sdata");
unsigned long boot_cpu_hartid;
static DEFINE_PER_CPU(struct cpu, cpu_devices);
static void __init parse_dtb(void)
{
/* Early scan of device tree from init memory */
if (early_init_dt_scan(dtb_early_va)) {
const char *name = of_flat_dt_get_machine_name();
if (name) {
pr_info("Machine model: %s\n", name);
dump_stack_set_arch_desc("%s (DT)", name);
}
} else {
pr_err("No DTB passed to the kernel\n");
}
#ifdef CONFIG_CMDLINE_FORCE
strlcpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
pr_info("Forcing kernel command line to: %s\n", boot_command_line);
#endif
}
void __init setup_arch(char **cmdline_p)
{
parse_dtb();
init_mm.start_code = (unsigned long) _stext;
init_mm.end_code = (unsigned long) _etext;
init_mm.end_data = (unsigned long) _edata;
init_mm.brk = (unsigned long) _end;
*cmdline_p = boot_command_line;
early_ioremap_setup();
jump_label_init();
parse_early_param();
efi_init();
setup_bootmem();
paging_init();
#if IS_ENABLED(CONFIG_BUILTIN_DTB)
unflatten_and_copy_device_tree();
#else
if (early_init_dt_verify(__va(dtb_early_pa)))
unflatten_device_tree();
else
pr_err("No DTB found in kernel mappings\n");
#endif
early_init_fdt_scan_reserved_mem();
misc_mem_init();
#ifdef CONFIG_SWIOTLB
swiotlb_init(1);
#endif
#ifdef CONFIG_KASAN
kasan_init();
#endif
#if IS_ENABLED(CONFIG_RISCV_SBI)
sbi_init();
#endif
#ifdef CONFIG_SMP
setup_smp();
#endif
riscv_fill_hwcap();
}
static int __init topology_init(void)
{
int i;
for_each_possible_cpu(i) {
struct cpu *cpu = &per_cpu(cpu_devices, i);
cpu->hotpluggable = cpu_has_hotplug(i);
register_cpu(cpu, i);
}
return 0;
}
subsys_initcall(topology_init);