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Diffstat (limited to 'drivers/lguest/segments.c')
-rw-r--r--drivers/lguest/segments.c28
1 files changed, 17 insertions, 11 deletions
diff --git a/drivers/lguest/segments.c b/drivers/lguest/segments.c
index ede46581351..c4fb424dfdd 100644
--- a/drivers/lguest/segments.c
+++ b/drivers/lguest/segments.c
@@ -81,8 +81,8 @@ static void fixup_gdt_table(struct lg_cpu *cpu, unsigned start, unsigned end)
* sometimes careless and leaves this as 0, even though it's
* running at privilege level 1. If so, we fix it here.
*/
- if ((cpu->arch.gdt[i].b & 0x00006000) == 0)
- cpu->arch.gdt[i].b |= (GUEST_PL << 13);
+ if (cpu->arch.gdt[i].dpl == 0)
+ cpu->arch.gdt[i].dpl |= GUEST_PL;
/*
* Each descriptor has an "accessed" bit. If we don't set it
@@ -90,7 +90,7 @@ static void fixup_gdt_table(struct lg_cpu *cpu, unsigned start, unsigned end)
* that entry into a segment register. But the GDT isn't
* writable by the Guest, so bad things can happen.
*/
- cpu->arch.gdt[i].b |= 0x00000100;
+ cpu->arch.gdt[i].type |= 0x1;
}
}
@@ -114,13 +114,19 @@ void setup_default_gdt_entries(struct lguest_ro_state *state)
/*
* The TSS segment refers to the TSS entry for this particular CPU.
- * Forgive the magic flags: the 0x8900 means the entry is Present, it's
- * privilege level 0 Available 386 TSS system segment, and the 0x67
- * means Saturn is eclipsed by Mercury in the twelfth house.
*/
- gdt[GDT_ENTRY_TSS].a = 0x00000067 | (tss << 16);
- gdt[GDT_ENTRY_TSS].b = 0x00008900 | (tss & 0xFF000000)
- | ((tss >> 16) & 0x000000FF);
+ gdt[GDT_ENTRY_TSS].a = 0;
+ gdt[GDT_ENTRY_TSS].b = 0;
+
+ gdt[GDT_ENTRY_TSS].limit0 = 0x67;
+ gdt[GDT_ENTRY_TSS].base0 = tss & 0xFFFF;
+ gdt[GDT_ENTRY_TSS].base1 = (tss >> 16) & 0xFF;
+ gdt[GDT_ENTRY_TSS].base2 = tss >> 24;
+ gdt[GDT_ENTRY_TSS].type = 0x9; /* 32-bit TSS (available) */
+ gdt[GDT_ENTRY_TSS].p = 0x1; /* Entry is present */
+ gdt[GDT_ENTRY_TSS].dpl = 0x0; /* Privilege level 0 */
+ gdt[GDT_ENTRY_TSS].s = 0x0; /* system segment */
+
}
/*
@@ -135,8 +141,8 @@ void setup_guest_gdt(struct lg_cpu *cpu)
*/
cpu->arch.gdt[GDT_ENTRY_KERNEL_CS] = FULL_EXEC_SEGMENT;
cpu->arch.gdt[GDT_ENTRY_KERNEL_DS] = FULL_SEGMENT;
- cpu->arch.gdt[GDT_ENTRY_KERNEL_CS].b |= (GUEST_PL << 13);
- cpu->arch.gdt[GDT_ENTRY_KERNEL_DS].b |= (GUEST_PL << 13);
+ cpu->arch.gdt[GDT_ENTRY_KERNEL_CS].dpl |= GUEST_PL;
+ cpu->arch.gdt[GDT_ENTRY_KERNEL_DS].dpl |= GUEST_PL;
}
/*H:650