From: Michael Tremer <michael.tremer@ipfire.org>
To: development@lists.ipfire.org
Subject: [PATCH 3/3] smt: Do not disable SMT in virtual machines
Date: Tue, 21 Jul 2020 10:36:41 +0000 [thread overview]
Message-ID: <20200721103641.30305-3-michael.tremer@ipfire.org> (raw)
In-Reply-To: <20200721103641.30305-1-michael.tremer@ipfire.org>
[-- Attachment #1: Type: text/plain, Size: 914 bytes --]
Processors in virtual machines are *virtual*. Therefore this
only degrades the performance of the guest, but does not increase
it's security.
This patch always leaves SMT enabled in all virtual environments.
Signed-off-by: Michael Tremer <michael.tremer(a)ipfire.org>
---
src/initscripts/system/smt | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/src/initscripts/system/smt b/src/initscripts/system/smt
index cc4128b2d..bfa7d57b3 100644
--- a/src/initscripts/system/smt
+++ b/src/initscripts/system/smt
@@ -20,6 +20,11 @@ case "${1}" in
exit 0
fi 2>/dev/null
+ # Do not disable SMT inside virtual machines
+ if [ -d "/sys/hypervisor" ]; then
+ exit 0
+ fi
+
# Disable SMT when the processor is vulnerable to Foreshadow or Fallout/ZombieLoad/RIDL
for vuln in l1tf mds; do
if [ -r "/sys/devices/system/cpu/vulnerabilities/${vuln}" ] && \
--
2.20.1
prev parent reply other threads:[~2020-07-21 10:36 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-21 10:36 [PATCH 1/3] oci: Add detection for Oracle Cloud Michael Tremer
2020-07-21 10:36 ` [PATCH 2/3] oci: Add automatic configuration script Michael Tremer
2020-07-21 10:36 ` Michael Tremer [this message]
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