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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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fc0091b3c8
By writing directly, a memory access violation can occur whilst hotplugging a CPU if the entry was previously marked read-only. Signed-off-by: Alex Nixon <alex.nixon@citrix.com> Cc: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
31 lines
729 B
C
31 lines
729 B
C
/*
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* SMP stuff which is common to all sub-architectures.
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*/
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#include <linux/module.h>
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#include <asm/smp.h>
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#ifdef CONFIG_X86_32
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DEFINE_PER_CPU(unsigned long, this_cpu_off);
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EXPORT_PER_CPU_SYMBOL(this_cpu_off);
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/*
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* Initialize the CPU's GDT. This is either the boot CPU doing itself
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* (still using the master per-cpu area), or a CPU doing it for a
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* secondary which will soon come up.
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*/
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__cpuinit void init_gdt(int cpu)
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{
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struct desc_struct gdt;
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pack_descriptor(&gdt, __per_cpu_offset[cpu], 0xFFFFF,
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0x2 | DESCTYPE_S, 0x8);
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gdt.s = 1;
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write_gdt_entry(get_cpu_gdt_table(cpu),
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GDT_ENTRY_PERCPU, &gdt, DESCTYPE_S);
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per_cpu(this_cpu_off, cpu) = __per_cpu_offset[cpu];
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per_cpu(cpu_number, cpu) = cpu;
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}
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#endif
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