x86/speculation: Add a conditional CS prefix to CALL_NOSPEC
Retpoline mitigation for spectre-v2 uses thunks for indirect branches. To
support this mitigation compilers add a CS prefix with
-mindirect-branch-cs-prefix. For an indirect branch in asm, this needs to
be added manually.
CS prefix is already being added to indirect branches in asm files, but not
in inline asm. Add CS prefix to CALL_NOSPEC for inline asm as well. There
is no JMP_NOSPEC for inline asm.
Reported-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Pawan Gupta <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Andrew Cooper <[email protected]
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
1 file changed
