push the lfence opcodes threshold to 70

1 files changed, 8 insertions, 5 deletions

diff --git a/spectre-meltdown-checker.sh b/spectre-meltdown-checker.sh
index 83e0019..9b78da3 100755
--- a/spectre-meltdown-checker.sh
+++ b/spectre-meltdown-checker.sh
@@ -1,7 +1,7 @@
 #! /bin/sh
 # Spectre & Meltdown checker
 # Stephane Lesimple
-VERSION=0.12
+VERSION=0.13
 
 # print status function
 pstatus()
@@ -117,13 +117,16 @@ else
 	else
 		# here we disassemble the kernel and count the number of occurences of the LFENCE opcode
 		# in non-patched kernels, this has been empirically determined as being around 40-50
-		# in patched kernels, this is more around 70-80
+		# in patched kernels, this is more around 70-80, sometimes way higher (100+)
+		# v0.13: 68 found in a 3.10.23-xxxx-std-ipv6-64 (with lots of modules compiled-in directly), which doesn't have the LFENCE patches,
+		# so let's push the threshold to 70.
+		# TODO LKML patch is starting to dump LFENCE in favor of the PAUSE opcode, we might need to check that (patch not stabilized yet)
 		nb_lfence=$(objdump -D "$vmlinux" | grep -wc lfence)
-		if [ "$nb_lfence" -lt 60 ]; then
-			pstatus red NO "only $nb_lfence opcodes found, should be >= 60"
+		if [ "$nb_lfence" -lt 70 ]; then
+			pstatus red NO "only $nb_lfence opcodes found, should be >= 70"
 			status=1
 		else
-			pstatus green YES "$nb_lfence opcodes found, which is >= 60"
+			pstatus green YES "$nb_lfence opcodes found, which is >= 70"
 			status=2
 		fi
 	fi