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arch/x86/power/cpu_32.c __save_processor_state calls read_cr4() only a i486 CPU doesn't have the CR4 register. Trying to read it produces an invalid opcode oops during suspend to disk. Use the safe rc4 reading op instead. If the value to be written is zero the write is skipped. arch/x86/power/hibernate_asm_32.S done: swapped the use of %eax and %ecx to use jecxz for the zero test and jump over store to %cr4. restore_image: s/%ecx/%eax/ to be consistent with done: In addition to __save_processor_state, acpi_save_state_mem, efi_call_phys_prelog, and efi_call_phys_epilog had checks added (acpi restore was in assembly and already had a check for non-zero). There were other reads and writes of CR4, but MCE and virtualization shouldn't be executed on a i486 anyway. Signed-off-by: David Fries <david@fries.net> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
113 lines
2.9 KiB
C
113 lines
2.9 KiB
C
/*
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* Extensible Firmware Interface
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*
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* Based on Extensible Firmware Interface Specification version 1.0
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*
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* Copyright (C) 1999 VA Linux Systems
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* Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
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* Copyright (C) 1999-2002 Hewlett-Packard Co.
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* David Mosberger-Tang <davidm@hpl.hp.com>
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* Stephane Eranian <eranian@hpl.hp.com>
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*
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* All EFI Runtime Services are not implemented yet as EFI only
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* supports physical mode addressing on SoftSDV. This is to be fixed
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* in a future version. --drummond 1999-07-20
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*
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* Implemented EFI runtime services and virtual mode calls. --davidm
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*
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* Goutham Rao: <goutham.rao@intel.com>
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* Skip non-WB memory and ignore empty memory ranges.
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*/
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#include <linux/kernel.h>
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#include <linux/types.h>
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#include <linux/ioport.h>
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#include <linux/efi.h>
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#include <asm/io.h>
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#include <asm/page.h>
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#include <asm/pgtable.h>
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#include <asm/tlbflush.h>
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#include <asm/efi.h>
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/*
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* To make EFI call EFI runtime service in physical addressing mode we need
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* prelog/epilog before/after the invocation to disable interrupt, to
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* claim EFI runtime service handler exclusively and to duplicate a memory in
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* low memory space say 0 - 3G.
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*/
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static unsigned long efi_rt_eflags;
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static pgd_t efi_bak_pg_dir_pointer[2];
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void efi_call_phys_prelog(void)
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{
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unsigned long cr4;
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unsigned long temp;
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struct desc_ptr gdt_descr;
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local_irq_save(efi_rt_eflags);
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/*
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* If I don't have PAE, I should just duplicate two entries in page
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* directory. If I have PAE, I just need to duplicate one entry in
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* page directory.
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*/
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cr4 = read_cr4_safe();
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if (cr4 & X86_CR4_PAE) {
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efi_bak_pg_dir_pointer[0].pgd =
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swapper_pg_dir[pgd_index(0)].pgd;
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swapper_pg_dir[0].pgd =
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swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
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} else {
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efi_bak_pg_dir_pointer[0].pgd =
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swapper_pg_dir[pgd_index(0)].pgd;
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efi_bak_pg_dir_pointer[1].pgd =
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swapper_pg_dir[pgd_index(0x400000)].pgd;
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swapper_pg_dir[pgd_index(0)].pgd =
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swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
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temp = PAGE_OFFSET + 0x400000;
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swapper_pg_dir[pgd_index(0x400000)].pgd =
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swapper_pg_dir[pgd_index(temp)].pgd;
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}
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/*
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* After the lock is released, the original page table is restored.
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*/
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__flush_tlb_all();
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gdt_descr.address = __pa(get_cpu_gdt_table(0));
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gdt_descr.size = GDT_SIZE - 1;
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load_gdt(&gdt_descr);
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}
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void efi_call_phys_epilog(void)
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{
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unsigned long cr4;
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struct desc_ptr gdt_descr;
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gdt_descr.address = (unsigned long)get_cpu_gdt_table(0);
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gdt_descr.size = GDT_SIZE - 1;
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load_gdt(&gdt_descr);
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cr4 = read_cr4_safe();
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if (cr4 & X86_CR4_PAE) {
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swapper_pg_dir[pgd_index(0)].pgd =
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efi_bak_pg_dir_pointer[0].pgd;
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} else {
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swapper_pg_dir[pgd_index(0)].pgd =
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efi_bak_pg_dir_pointer[0].pgd;
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swapper_pg_dir[pgd_index(0x400000)].pgd =
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efi_bak_pg_dir_pointer[1].pgd;
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}
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/*
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* After the lock is released, the original page table is restored.
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*/
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__flush_tlb_all();
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local_irq_restore(efi_rt_eflags);
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}
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