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x86/speculation: Remove the extra #ifdef around CALL_NOSPEC

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commit c8c81458863ab686cda4fe1e603fccaae0f12460 upstream.

Commit:

  010c4a461c1d ("x86/speculation: Simplify and make CALL_NOSPEC consistent")

added an #ifdef CONFIG_MITIGATION_RETPOLINE around the CALL_NOSPEC definition.
This is not required as this code is already under a larger #ifdef.

Remove the extra #ifdef, no functional change.

vmlinux size remains same before and after this change:

 CONFIG_MITIGATION_RETPOLINE=y:
      text       data        bss         dec        hex    filename
  25434752    7342290    2301212    35078254    217406e    vmlinux.before
  25434752    7342290    2301212    35078254    217406e    vmlinux.after

 # CONFIG_MITIGATION_RETPOLINE is not set:
      text       data        bss         dec        hex    filename
  22943094    6214994    1550152    30708240    1d49210    vmlinux.before
  22943094    6214994    1550152    30708240    1d49210    vmlinux.after

Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Link: https://lore.kernel.org/r/20250320-call-nospec-extra-ifdef-v1-1-d9b084d24820@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Pawan Gupta
2025-03-20 11:13:15 -07:00
committed by Greg Kroah-Hartman
parent 9ebe6f1bd2
commit f23d4f4aeb
1 changed files with 0 additions and 4 deletions
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4
arch/x86/include/asm/nospec-branch.h
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@@ -452,12 +452,8 @@ static inline void call_depth_return_thunk(void) {}
* Inline asm uses the %V modifier which is only in newer GCC
* which is ensured when CONFIG_MITIGATION_RETPOLINE is defined.
*/
#ifdef CONFIG_MITIGATION_RETPOLINE
#define CALL_NOSPEC __CS_PREFIX("%V[thunk_target]") \
"call __x86_indirect_thunk_%V[thunk_target]\n"
#else
#define CALL_NOSPEC "call *%[thunk_target]\n"
#endif
# define THUNK_TARGET(addr) [thunk_target] "r" (addr)