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    Subject[PATCH 5/5] x86/entry_64.S: get rid of int_ret_from_sys_call_fixup
    Date
    With FIXUP_TOP_OF_STACK removed, this intermediate jump
    is unnecessary.

    Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
    CC: Linus Torvalds <torvalds@linux-foundation.org>
    CC: Steven Rostedt <rostedt@goodmis.org>
    CC: Ingo Molnar <mingo@kernel.org>
    CC: Borislav Petkov <bp@alien8.de>
    CC: "H. Peter Anvin" <hpa@zytor.com>
    CC: Andy Lutomirski <luto@amacapital.net>
    CC: Oleg Nesterov <oleg@redhat.com>
    CC: Frederic Weisbecker <fweisbec@gmail.com>
    CC: Alexei Starovoitov <ast@plumgrid.com>
    CC: Will Drewry <wad@chromium.org>
    CC: Kees Cook <keescook@chromium.org>
    CC: x86@kernel.org
    CC: linux-kernel@vger.kernel.org
    ---
    arch/x86/kernel/entry_64.S | 5 +----
    1 file changed, 1 insertion(+), 4 deletions(-)

    diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
    index 829459e..8d7f905 100644
    --- a/arch/x86/kernel/entry_64.S
    +++ b/arch/x86/kernel/entry_64.S
    @@ -268,7 +268,7 @@ system_call_fastpath:
    */
    ret_from_sys_call:
    testl $_TIF_ALLWORK_MASK,TI_flags+THREAD_INFO(%rsp,SIZEOF_PTREGS)
    - jnz int_ret_from_sys_call_fixup /* Go the the slow path */
    + jnz int_ret_from_sys_call /* Go the slow path */

    LOCKDEP_SYS_EXIT
    DISABLE_INTERRUPTS(CLBR_NONE)
    @@ -293,9 +293,6 @@ ret_from_sys_call:

    CFI_RESTORE_STATE

    -int_ret_from_sys_call_fixup:
    - jmp int_ret_from_sys_call
    -
    /* Do syscall entry tracing */
    tracesys:
    movq %rsp, %rdi
    --
    1.8.1.4


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