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x86: fix x86-32 early fixmap initialization.

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pageexec@freemail.hu writes:

> i've just noticed that the chunk in i386/kernel/head.S ended up in a
> weird place, namely, it's not going to be executed as it's just after
> a 'jmp 3f' and before startup_32_smp, probably not what you intended.
> on a sidenote, the whole thing can be done in a single insn, like:
>
> movl $(swapper_pg_pmd - __PAGE_OFFSET + 0x067), (swapper_pg_dir -
> __PAGE_OFFSET+ 4092)

Thanks for the reminder I thought we had fixed this problem a while ago.

Needed to get fixed virtual address for USB debug and earlycon with mmio.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Eric W. Biederman
2007-12-01 18:34:06 -07:00
committed by Ingo Molnar
parent 0c1b272406
commit 17d57a9206
1 changed files with 6 additions and 6 deletions
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12
arch/x86/kernel/head_32.S
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@@ -193,6 +193,12 @@ default_entry:
jb 10b jb 10b
movl %edi,(init_pg_tables_end - __PAGE_OFFSET) movl %edi,(init_pg_tables_end - __PAGE_OFFSET)
/* Do an early initialization of the fixmap area */
movl $(swapper_pg_dir - __PAGE_OFFSET), %edx
movl $(swapper_pg_pmd - __PAGE_OFFSET), %eax
addl $0x007, %eax /* 0x007 = PRESENT+RW+USER */
movl %eax, 4092(%edx)
xorl %ebx,%ebx /* This is the boot CPU (BSP) */ xorl %ebx,%ebx /* This is the boot CPU (BSP) */
jmp 3f jmp 3f
/* /*
@@ -208,12 +214,6 @@ default_entry:
.section .init.text,"ax",@progbits .section .init.text,"ax",@progbits
#endif #endif
/* Do an early initialization of the fixmap area */
movl $(swapper_pg_dir - __PAGE_OFFSET), %edx
movl $(swapper_pg_pmd - __PAGE_OFFSET), %eax
addl $0x007, %eax /* 0x007 = PRESENT+RW+USER */
movl %eax, 4092(%edx)
#ifdef CONFIG_SMP #ifdef CONFIG_SMP
ENTRY(startup_32_smp) ENTRY(startup_32_smp)
cld cld