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    Subject[PATCH 04/24] x86/entry: Expose the address of .Lgs_change to traps.c
    Date
    From: Lai Jiangshan <laijs@linux.alibaba.com>

    The address of .Lgs_change will be used in traps.c in later patch when
    some entry code is implemented in traps.c. So the address of .Lgs_change
    is exposed to traps.c for preparation.

    The label .Lgs_change is still needed in ASM code for extable.

    Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
    ---
    arch/x86/entry/entry_64.S | 3 ++-
    arch/x86/entry/traps.c | 1 +
    2 files changed, 3 insertions(+), 1 deletion(-)

    diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
    index e38a4cf795d9..9164e85b36b8 100644
    --- a/arch/x86/entry/entry_64.S
    +++ b/arch/x86/entry/entry_64.S
    @@ -729,6 +729,7 @@ _ASM_NOKPROBE(common_interrupt_return)
    SYM_FUNC_START(asm_load_gs_index)
    FRAME_BEGIN
    swapgs
    +SYM_INNER_LABEL(asm_load_gs_index_gs_change, SYM_L_GLOBAL)
    .Lgs_change:
    movl %edi, %gs
    2: ALTERNATIVE "", "mfence", X86_BUG_SWAPGS_FENCE
    @@ -1011,7 +1012,7 @@ SYM_CODE_START_LOCAL(error_entry)
    movl %ecx, %eax /* zero extend */
    cmpq %rax, RIP+8(%rsp)
    je .Lbstep_iret
    - cmpq $.Lgs_change, RIP+8(%rsp)
    + cmpq $asm_load_gs_index_gs_change, RIP+8(%rsp)
    jne .Lerror_entry_done_lfence

    /*
    diff --git a/arch/x86/entry/traps.c b/arch/x86/entry/traps.c
    index 7869343473b7..f71db7934f90 100644
    --- a/arch/x86/entry/traps.c
    +++ b/arch/x86/entry/traps.c
    @@ -67,6 +67,7 @@
    #include <asm/proto.h>

    extern unsigned char native_irq_return_iret[];
    +extern unsigned char asm_load_gs_index_gs_change[];

    #else
    #include <asm/processor-flags.h>
    --
    2.19.1.6.gb485710b
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