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-rw-r--r--Documentation/admin-guide/kernel-parameters.txt44
1 files changed, 44 insertions, 0 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 607a8937f175..8724c2c580b8 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2149,6 +2149,23 @@
different crypto accelerators. This option can be used
to achieve best performance for particular HW.
+ indirect_target_selection= [X86,Intel] Mitigation control for Indirect
+ Target Selection(ITS) bug in Intel CPUs. Updated
+ microcode is also required for a fix in IBPB.
+
+ on: Enable mitigation (default).
+ off: Disable mitigation.
+ force: Force the ITS bug and deploy default
+ mitigation.
+ vmexit: Only deploy mitigation if CPU is affected by
+ guest/host isolation part of ITS.
+ stuff: Deploy RSB-fill mitigation when retpoline is
+ also deployed. Otherwise, deploy the default
+ mitigation.
+
+ For details see:
+ Documentation/admin-guide/hw-vuln/indirect-target-selection.rst
+
init= [KNL]
Format: <full_path>
Run specified binary instead of /sbin/init as init
@@ -3510,6 +3527,7 @@
expose users to several CPU vulnerabilities.
Equivalent to: if nokaslr then kpti=0 [ARM64]
gather_data_sampling=off [X86]
+ indirect_target_selection=off [X86]
kvm.nx_huge_pages=off [X86]
l1tf=off [X86]
mds=off [X86]
@@ -3530,6 +3548,7 @@
srbds=off [X86,INTEL]
ssbd=force-off [ARM64]
tsx_async_abort=off [X86]
+ vmscape=off [X86]
Exceptions:
This does not have any effect on
@@ -6243,6 +6262,8 @@
Selecting 'on' will also enable the mitigation
against user space to user space task attacks.
+ Selecting specific mitigation does not force enable
+ user mitigations.
Selecting 'off' will disable both the kernel and
the user space protections.
@@ -6973,6 +6994,19 @@
having this key zero'ed is acceptable. E.g. in testing
scenarios.
+ tsa= [X86] Control mitigation for Transient Scheduler
+ Attacks on AMD CPUs. Search the following in your
+ favourite search engine for more details:
+
+ "Technical guidance for mitigating transient scheduler
+ attacks".
+
+ off - disable the mitigation
+ on - enable the mitigation (default)
+ user - mitigate only user/kernel transitions
+ vm - mitigate only guest/host transitions
+
+
tsc= Disable clocksource stability checks for TSC.
Format: <string>
[x86] reliable: mark tsc clocksource as reliable, this
@@ -7392,6 +7426,16 @@
vmpoff= [KNL,S390] Perform z/VM CP command after power off.
Format: <command>
+ vmscape= [X86] Controls mitigation for VMscape attacks.
+ VMscape attacks can leak information from a userspace
+ hypervisor to a guest via speculative side-channels.
+
+ off - disable the mitigation
+ ibpb - use Indirect Branch Prediction Barrier
+ (IBPB) mitigation (default)
+ force - force vulnerability detection even on
+ unaffected processors
+
vsyscall= [X86-64,EARLY]
Controls the behavior of vsyscalls (i.e. calls to
fixed addresses of 0xffffffffff600x00 from legacy