From: Eric W. Biederman Date: Sun, 2 Dec 2007 01:34:06 +0000 (-0700) Subject: x86: fix x86-32 early fixmap initialization. X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=17d57a9206b4de6ad082ac9f2d2346985abbd2aa;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git x86: fix x86-32 early fixmap initialization. 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" Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index 374b7ece896..ac0637a6d71 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -193,6 +193,12 @@ default_entry: jb 10b 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) */ jmp 3f /* @@ -208,12 +214,6 @@ default_entry: .section .init.text,"ax",@progbits #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 ENTRY(startup_32_smp) cld