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| author |   H. Peter Anvin <hpa@zytor.com> | 2009-08-31 13:59:53 -0700 |
|---|---|---|
| committer | H. Peter Anvin <hpa@zytor.com> | 2009-08-31 15:14:47 -0700 |
| commit | 79c5dca3619d6ae15815eec14cd7a43db5f38b47 (patch) | |
| tree | f2a10abc4862d1812a08dcb44bc5a7a8a78ec57f | |
| parent | x86, asm: Make _ASM_EXTABLE() usable from assembly code (diff) | |
| download | linux-dev-79c5dca3619d6ae15815eec14cd7a43db5f38b47.tar.xz linux-dev-79c5dca3619d6ae15815eec14cd7a43db5f38b47.zip | |
x86, msr: CFI annotations, cleanups for msr-reg.S
Add CFI annotations for native_{rd,wr}msr_safe_regs().
Simplify the 64-bit implementation: we don't allow the upper half
registers to be set, and so we can use them to carry state across the
operation.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Borislav Petkov <petkovbb@gmail.com>
LKML-Reference: <1251705011-18636-1-git-send-email-petkovbb@gmail.com>
| -rw-r--r-- | arch/x86/lib/msr-reg.S | 80 |
1 files changed, 42 insertions, 38 deletions
diff --git a/arch/x86/lib/msr-reg.S b/arch/x86/lib/msr-reg.S index 51f1bb3f8c79..9e8cdcf5d73c 100644 --- a/arch/x86/lib/msr-reg.S +++ b/arch/x86/lib/msr-reg.S @@ -1,5 +1,6 @@ #include <linux/linkage.h> #include <linux/errno.h> +#include <asm/dwarf2.h> #include <asm/asm.h> #include <asm/msr.h> @@ -12,10 +13,11 @@ */ .macro op_safe_regs op:req ENTRY(native_\op\()_safe_regs) - push %rbx - push %rbp - push $0 /* Return value */ - push %rdi + CFI_STARTPROC + pushq_cfi %rbx + pushq_cfi %rbp + movq %rdi, %r10 /* Save pointer */ + xorl %r11d, %r11d /* Return value */ movl (%rdi), %eax movl 4(%rdi), %ecx movl 8(%rdi), %edx @@ -23,27 +25,26 @@ ENTRY(native_\op\()_safe_regs) movl 20(%rdi), %ebp movl 24(%rdi), %esi movl 28(%rdi), %edi + CFI_REMEMBER_STATE 1: \op -2: movl %edi, %r10d - pop %rdi - movl %eax, (%rdi) - movl %ecx, 4(%rdi) - movl %edx, 8(%rdi) - movl %ebx, 12(%rdi) - movl %ebp, 20(%rdi) - movl %esi, 24(%rdi) - movl %r10d, 28(%rdi) - pop %rax - pop %rbp - pop %rbx +2: movl %eax, (%r10) + movl %r11d, %eax /* Return value */ + movl %ecx, 4(%r10) + movl %edx, 8(%r10) + movl %ebx, 12(%r10) + movl %ebp, 20(%r10) + movl %esi, 24(%r10) + movl %edi, 28(%r10) + popq_cfi %rbp + popq_cfi %rbx ret 3: - movq $-EIO, 8(%rsp) + CFI_RESTORE_STATE + movl $-EIO, %r11d jmp 2b - .section __ex_table,"ax" - .balign 4 - .quad 1b, 3b - .previous + + _ASM_EXTABLE(1b, 3b) + CFI_ENDPROC ENDPROC(native_\op\()_safe_regs) .endm @@ -51,12 +52,13 @@ ENDPROC(native_\op\()_safe_regs) .macro op_safe_regs op:req ENTRY(native_\op\()_safe_regs) - push %ebx - push %ebp - push %esi - push %edi - push $0 /* Return value */ - push %eax + CFI_STARTPROC + pushl_cfi %ebx + pushl_cfi %ebp + pushl_cfi %esi + pushl_cfi %edi + pushl_cfi $0 /* Return value */ + pushl_cfi %eax movl 4(%eax), %ecx movl 8(%eax), %edx movl 12(%eax), %ebx @@ -64,30 +66,32 @@ ENTRY(native_\op\()_safe_regs) movl 24(%eax), %esi movl 28(%eax), %edi movl (%eax), %eax + CFI_REMEMBER_STATE 1: \op -2: push %eax +2: pushl_cfi %eax movl 4(%esp), %eax - pop (%eax) + popl_cfi (%eax) addl $4, %esp + CFI_ADJUST_CFA_OFFSET -4 movl %ecx, 4(%eax) movl %edx, 8(%eax) movl %ebx, 12(%eax) movl %ebp, 20(%eax) movl %esi, 24(%eax) movl %edi, 28(%eax) - pop %eax - pop %edi - pop %esi - pop %ebp - pop %ebx + popl_cfi %eax + popl_cfi %edi + popl_cfi %esi + popl_cfi %ebp + popl_cfi %ebx ret 3: + CFI_RESTORE_STATE movl $-EIO, 4(%esp) jmp 2b - .section __ex_table,"ax" - .balign 4 - .long 1b, 3b - .previous + + _ASM_EXTABLE(1b, 3b) + CFI_ENDPROC ENDPROC(native_\op\()_safe_regs) .endm |