提交 166df91d 编写于 作者: B Borislav Petkov 提交者: H. Peter Anvin

x86, head_32: Remove i386 pieces

Remove code fragments detecting a 386 CPU since we don't support those
anymore. Also, do not do alignment checks because they're done only at
CPL3. Also, no need to preserve EFLAGS.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1360592538-10643-2-git-send-email-bp@alien8.deSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
上级 8ecba5af
...@@ -395,29 +395,20 @@ default_entry: ...@@ -395,29 +395,20 @@ default_entry:
call *%eax call *%eax
1: 1:
/* check if it is 486 or 386. */
/* /*
* XXX - this does a lot of unnecessary setup. Alignment checks don't * Check if it is 486
* apply at our cpl of 0 and the stack ought to be aligned already, and
* we don't need to preserve eflags.
*/ */
movl $-1,X86_CPUID # -1 for no CPUID initially movl $-1,X86_CPUID # -1 for no CPUID initially
movb $3,X86 # at least 386 movb $4,X86 # at least 486
pushfl # push EFLAGS pushfl # push EFLAGS
popl %eax # get EFLAGS popl %eax # get EFLAGS
movl %eax,%ecx # save original EFLAGS movl %eax,%ecx # save original EFLAGS
xorl $0x240000,%eax # flip AC and ID bits in EFLAGS xorl $0x200000,%eax # flip ID bit in EFLAGS
pushl %eax # copy to EFLAGS pushl %eax # copy to EFLAGS
popfl # set EFLAGS popfl # set EFLAGS
pushfl # get new EFLAGS pushfl # get new EFLAGS
popl %eax # put it in eax popl %eax # put it in eax
xorl %ecx,%eax # change in flags xorl %ecx,%eax # change in flags
pushl %ecx # restore original EFLAGS
popfl
testl $0x40000,%eax # check if AC bit changed
je is386
movb $4,X86 # at least 486
testl $0x200000,%eax # check if ID bit changed testl $0x200000,%eax # check if ID bit changed
je is486 je is486
...@@ -445,10 +436,7 @@ default_entry: ...@@ -445,10 +436,7 @@ default_entry:
movl %edx,X86_CAPABILITY movl %edx,X86_CAPABILITY
is486: movl $0x50022,%ecx # set AM, WP, NE and MP is486: movl $0x50022,%ecx # set AM, WP, NE and MP
jmp 2f movl %cr0,%eax
is386: movl $2,%ecx # set MP
2: movl %cr0,%eax
andl $0x80000011,%eax # Save PG,PE,ET andl $0x80000011,%eax # Save PG,PE,ET
orl %ecx,%eax orl %ecx,%eax
movl %eax,%cr0 movl %eax,%cr0
......
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