[PATCH AUTOSEL 5.4 08/17] crypto: x86/chacha20 - Avoid spurious jumps to other functions
From: Sasha Levin
Date: Wed Apr 06 2022 - 21:32:11 EST
From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
[ Upstream commit 4327d168515fd8b5b92fa1efdf1d219fb6514460 ]
The chacha_Nblock_xor_avx512vl() functions all have their own,
identical, .LdoneN label, however in one particular spot {2,4} jump to
the 8 version instead of their own. Resulting in:
arch/x86/crypto/chacha-x86_64.o: warning: objtool: chacha_2block_xor_avx512vl() falls through to next function chacha_8block_xor_avx512vl()
arch/x86/crypto/chacha-x86_64.o: warning: objtool: chacha_4block_xor_avx512vl() falls through to next function chacha_8block_xor_avx512vl()
Make each function consistently use its own done label.
Reported-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Martin Willi <martin@xxxxxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/x86/crypto/chacha-avx512vl-x86_64.S | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/crypto/chacha-avx512vl-x86_64.S b/arch/x86/crypto/chacha-avx512vl-x86_64.S
index 848f9c75fd4f..596f91e3a774 100644
--- a/arch/x86/crypto/chacha-avx512vl-x86_64.S
+++ b/arch/x86/crypto/chacha-avx512vl-x86_64.S
@@ -172,7 +172,7 @@ ENTRY(chacha_2block_xor_avx512vl)
# xor remaining bytes from partial register into output
mov %rcx,%rax
and $0xf,%rcx
- jz .Ldone8
+ jz .Ldone2
mov %rax,%r9
and $~0xf,%r9
@@ -438,7 +438,7 @@ ENTRY(chacha_4block_xor_avx512vl)
# xor remaining bytes from partial register into output
mov %rcx,%rax
and $0xf,%rcx
- jz .Ldone8
+ jz .Ldone4
mov %rax,%r9
and $~0xf,%r9
--
2.35.1