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	This is a fix against the issue that crash dump kernel may hang up
during booting, which can happen on any ACPI-based system with "ACPI
Reclaim Memory."
(kernel messages after panic kicked off kdump)
	   (snip...)
	Bye!
	   (snip...)
	ACPI: Core revision 20170728
	pud=000000002e7d0003, *pmd=000000002e7c0003, *pte=00e8000039710707
	Internal error: Oops: 96000021 [#1] SMP
	Modules linked in:
	CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.0-rc6 #1
	task: ffff000008d05180 task.stack: ffff000008cc0000
	PC is at acpi_ns_lookup+0x25c/0x3c0
	LR is at acpi_ds_load1_begin_op+0xa4/0x294
	   (snip...)
	Process swapper/0 (pid: 0, stack limit = 0xffff000008cc0000)
	Call trace:
	   (snip...)
	[<ffff0000084a6764>] acpi_ns_lookup+0x25c/0x3c0
	[<ffff00000849b4f8>] acpi_ds_load1_begin_op+0xa4/0x294
	[<ffff0000084ad4ac>] acpi_ps_build_named_op+0xc4/0x198
	[<ffff0000084ad6cc>] acpi_ps_create_op+0x14c/0x270
	[<ffff0000084acfa8>] acpi_ps_parse_loop+0x188/0x5c8
	[<ffff0000084ae048>] acpi_ps_parse_aml+0xb0/0x2b8
	[<ffff0000084a8e10>] acpi_ns_one_complete_parse+0x144/0x184
	[<ffff0000084a8e98>] acpi_ns_parse_table+0x48/0x68
	[<ffff0000084a82cc>] acpi_ns_load_table+0x4c/0xdc
	[<ffff0000084b32f8>] acpi_tb_load_namespace+0xe4/0x264
	[<ffff000008baf9b4>] acpi_load_tables+0x48/0xc0
	[<ffff000008badc20>] acpi_early_init+0x9c/0xd0
	[<ffff000008b70d50>] start_kernel+0x3b4/0x43c
	Code: b9008fb9 2a000318 36380054 32190318 (b94002c0)
	---[ end trace c46ed37f9651c58e ]---
	Kernel panic - not syncing: Fatal exception
	Rebooting in 10 seconds..
(diagnosis)
* This fault is a data abort, alignment fault (ESR=0x96000021)
  during reading out ACPI table.
* Initial ACPI tables are normally stored in system ram and marked as
  "ACPI Reclaim memory" by the firmware.
* After the commit f56ab9a5b7 ("efi/arm: Don't mark ACPI reclaim
  memory as MEMBLOCK_NOMAP"), those regions are differently handled
  as they are "memblock-reserved", without NOMAP bit.
* So they are now excluded from device tree's "usable-memory-range"
  which kexec-tools determines based on a current view of /proc/iomem.
* When crash dump kernel boots up, it tries to accesses ACPI tables by
  mapping them with ioremap(), not ioremap_cache(), in acpi_os_ioremap()
  since they are no longer part of mapped system ram.
* Given that ACPI accessor/helper functions are compiled in without
  unaligned access support (ACPI_MISALIGNMENT_NOT_SUPPORTED),
  any unaligned access to ACPI tables can cause a fatal panic.
With this patch, acpi_os_ioremap() always honors memory attribute
information provided by the firmware (EFI) and retaining cacheability
allows the kernel safe access to ACPI tables.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by and Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
		
	
			
		
			
				
	
	
		
			156 lines
		
	
	
	
		
			4.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			156 lines
		
	
	
	
		
			4.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 *  Copyright (C) 2013-2014, Linaro Ltd.
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 *	Author: Al Stone <al.stone@linaro.org>
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 *	Author: Graeme Gregory <graeme.gregory@linaro.org>
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 *	Author: Hanjun Guo <hanjun.guo@linaro.org>
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 *
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 *  This program is free software; you can redistribute it and/or modify
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 *  it under the terms of the GNU General Public License version 2 as
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 *  published by the Free Software Foundation;
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 */
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#ifndef _ASM_ACPI_H
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#define _ASM_ACPI_H
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#include <linux/efi.h>
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#include <linux/memblock.h>
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#include <linux/psci.h>
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#include <asm/cputype.h>
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#include <asm/io.h>
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#include <asm/smp_plat.h>
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#include <asm/tlbflush.h>
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/* Macros for consistency checks of the GICC subtable of MADT */
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#define ACPI_MADT_GICC_LENGTH	\
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	(acpi_gbl_FADT.header.revision < 6 ? 76 : 80)
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#define BAD_MADT_GICC_ENTRY(entry, end)					\
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	(!(entry) || (entry)->header.length != ACPI_MADT_GICC_LENGTH ||	\
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	(unsigned long)(entry) + ACPI_MADT_GICC_LENGTH > (end))
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/* Basic configuration for ACPI */
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#ifdef	CONFIG_ACPI
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pgprot_t __acpi_get_mem_attribute(phys_addr_t addr);
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/* ACPI table mapping after acpi_permanent_mmap is set */
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static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys,
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					    acpi_size size)
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{
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	/* For normal memory we already have a cacheable mapping. */
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	if (memblock_is_map_memory(phys))
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		return (void __iomem *)__phys_to_virt(phys);
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	/*
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	 * We should still honor the memory's attribute here because
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	 * crash dump kernel possibly excludes some ACPI (reclaim)
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	 * regions from memblock list.
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	 */
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	return __ioremap(phys, size, __acpi_get_mem_attribute(phys));
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}
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#define acpi_os_ioremap acpi_os_ioremap
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typedef u64 phys_cpuid_t;
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#define PHYS_CPUID_INVALID INVALID_HWID
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#define acpi_strict 1	/* No out-of-spec workarounds on ARM64 */
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extern int acpi_disabled;
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extern int acpi_noirq;
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extern int acpi_pci_disabled;
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static inline void disable_acpi(void)
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{
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	acpi_disabled = 1;
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	acpi_pci_disabled = 1;
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	acpi_noirq = 1;
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}
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static inline void enable_acpi(void)
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{
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	acpi_disabled = 0;
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	acpi_pci_disabled = 0;
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	acpi_noirq = 0;
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}
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/*
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 * The ACPI processor driver for ACPI core code needs this macro
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 * to find out this cpu was already mapped (mapping from CPU hardware
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 * ID to CPU logical ID) or not.
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 */
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#define cpu_physical_id(cpu) cpu_logical_map(cpu)
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/*
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 * It's used from ACPI core in kdump to boot UP system with SMP kernel,
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 * with this check the ACPI core will not override the CPU index
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 * obtained from GICC with 0 and not print some error message as well.
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 * Since MADT must provide at least one GICC structure for GIC
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 * initialization, CPU will be always available in MADT on ARM64.
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 */
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static inline bool acpi_has_cpu_in_madt(void)
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{
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	return true;
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}
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struct acpi_madt_generic_interrupt *acpi_cpu_get_madt_gicc(int cpu);
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static inline u32 get_acpi_id_for_cpu(unsigned int cpu)
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{
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	return	acpi_cpu_get_madt_gicc(cpu)->uid;
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}
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static inline void arch_fix_phys_package_id(int num, u32 slot) { }
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void __init acpi_init_cpus(void);
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#else
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static inline void acpi_init_cpus(void) { }
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#endif /* CONFIG_ACPI */
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#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
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bool acpi_parking_protocol_valid(int cpu);
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void __init
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acpi_set_mailbox_entry(int cpu, struct acpi_madt_generic_interrupt *processor);
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#else
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static inline bool acpi_parking_protocol_valid(int cpu) { return false; }
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static inline void
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acpi_set_mailbox_entry(int cpu, struct acpi_madt_generic_interrupt *processor)
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{}
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#endif
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static inline const char *acpi_get_enable_method(int cpu)
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{
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	if (acpi_psci_present())
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		return "psci";
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	if (acpi_parking_protocol_valid(cpu))
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		return "parking-protocol";
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	return NULL;
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}
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#ifdef	CONFIG_ACPI_APEI
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/*
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 * acpi_disable_cmcff is used in drivers/acpi/apei/hest.c for disabling
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 * IA-32 Architecture Corrected Machine Check (CMC) Firmware-First mode
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 * with a kernel command line parameter "acpi=nocmcoff". But we don't
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 * have this IA-32 specific feature on ARM64, this definition is only
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 * for compatibility.
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 */
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#define acpi_disable_cmcff 1
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static inline pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
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{
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	return __acpi_get_mem_attribute(addr);
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}
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#endif /* CONFIG_ACPI_APEI */
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#ifdef CONFIG_ACPI_NUMA
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int arm64_acpi_numa_init(void);
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int acpi_numa_get_nid(unsigned int cpu);
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void acpi_map_cpus_to_nodes(void);
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#else
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static inline int arm64_acpi_numa_init(void) { return -ENOSYS; }
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static inline int acpi_numa_get_nid(unsigned int cpu) { return NUMA_NO_NODE; }
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static inline void acpi_map_cpus_to_nodes(void) { }
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#endif /* CONFIG_ACPI_NUMA */
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#define ACPI_TABLE_UPGRADE_MAX_PHYS MEMBLOCK_ALLOC_ACCESSIBLE
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#endif /*_ASM_ACPI_H*/
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