x86, realmode: header for trampoline code
Added header for trampoline code that can be used to supply
input data to it. This makes interface between real mode code
and kernel cleaner and simpler. Replaced two confusing pointers
to level4 pgt in trampoline_64.S with a single pointer to the
beginning of the page table.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-21-git-send-email-jarkko.sakkinen@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
diff --git a/arch/x86/kernel/realmode.c b/arch/x86/kernel/realmode.c
index 632c810..712fba8 100644
--- a/arch/x86/kernel/realmode.c
+++ b/arch/x86/kernel/realmode.c
@@ -17,8 +17,11 @@
u16 *seg;
int i;
unsigned char *base;
-
+ struct trampoline_header *trampoline_header;
size_t size = PAGE_ALIGN(real_mode_blob_end - real_mode_blob);
+#ifdef CONFIG_X86_64
+ u64 *trampoline_pgd;
+#endif
/* Has to be in very low memory so we can execute real-mode AP code. */
mem = memblock_find_in_range(0, 1<<20, size, PAGE_SIZE);
@@ -28,7 +31,6 @@
base = __va(mem);
memblock_reserve(mem, size);
real_mode_header = (struct real_mode_header *) base;
-
printk(KERN_DEBUG "Base memory trampoline at [%p] %llx size %zu\n",
base, (unsigned long long)mem, size);
@@ -53,18 +55,19 @@
*ptr += __pa(base);
}
+ /* Must be perfomed *after* relocation. */
+ trampoline_header = (struct trampoline_header *)
+ __va(real_mode_header->trampoline_header);
+
#ifdef CONFIG_X86_32
- *((u32 *)__va(real_mode_header->startup_32_smp)) = __pa(startup_32_smp);
- *((u32 *)__va(real_mode_header->boot_gdt)) = __pa(boot_gdt);
+ trampoline_header->start = __pa(startup_32_smp);
+ trampoline_header->gdt_limit = __BOOT_DS + 7;
+ trampoline_header->gdt_base = __pa(boot_gdt);
#else
- *((u64 *) __va(real_mode_header->startup_64_smp)) =
- (u64)secondary_startup_64;
-
- *((u64 *) __va(real_mode_header->level3_ident_pgt)) =
- __pa(level3_ident_pgt) + _KERNPG_TABLE;
-
- *((u64 *) __va(real_mode_header->level3_kernel_pgt)) =
- __pa(level3_kernel_pgt) + _KERNPG_TABLE;
+ trampoline_header->start = (u64) secondary_startup_64;
+ trampoline_pgd = (u64 *) __va(real_mode_header->trampoline_pgd);
+ trampoline_pgd[0] = __pa(level3_ident_pgt) + _KERNPG_TABLE;
+ trampoline_pgd[511] = __pa(level3_kernel_pgt) + _KERNPG_TABLE;
#endif
}
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index b8c0661..757c4b1 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -667,7 +667,7 @@
volatile u32 *trampoline_status =
(volatile u32 *) __va(real_mode_header->trampoline_status);
/* start_ip had better be page-aligned! */
- unsigned long start_ip = real_mode_header->trampoline_data;
+ unsigned long start_ip = real_mode_header->trampoline_start;
unsigned long boot_error = 0;
int timeout;