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Subject[PATCH 1/1] x86/speculation, objtool: Annotate indirect calls/jumps for objtool on 32bit
Date
In 9e0e3c5130e9 ("x86/speculation, objtool: Annotate indirect calls/jumps
for objtool") we added annotations for CALL_NOSPEC/JMP_NOSPEC on x86 64bit.
We did not annotate the 32bit path. Annotate it similarly.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
---
arch/x86/include/asm/nospec-branch.h | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

While reviewing indirect calls in our builds I noted that the
i386 retpoline CALL_NOSPEC is not annotated safe even though
its amd64 equivalent is. I cannot see any reason this is not
also inherantly safe. Peter was there a reason that you did
not annotate this one too? Anyhow, on the assumption this was
just missed, this patch annotates it.

-apw

diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index d0dabeae0505..07886162bdf8 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -183,7 +183,10 @@
* otherwise we'll run out of registers. We don't care about CET
* here, anyway.
*/
-# define CALL_NOSPEC ALTERNATIVE("call *%[thunk_target]\n", \
+# define CALL_NOSPEC \
+ ALTERNATIVE( \
+ ANNOTATE_RETPOLINE_SAFE \
+ "call *%[thunk_target]\n", \
" jmp 904f;\n" \
" .align 16\n" \
"901: call 903f;\n" \
--
2.15.1
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