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-rw-r--r--Documentation/admin-guide/kernel-parameters.txt65
-rw-r--r--Documentation/admin-guide/security-bugs.rst21
2 files changed, 73 insertions, 13 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 81d1d5a74728..aefd358a5ca3 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -856,7 +856,8 @@
causing system reset or hang due to sending
INIT from AP to BSP.
- disable_counter_freezing [HW]
+ perf_v4_pmi= [X86,INTEL]
+ Format: <bool>
Disable Intel PMU counter freezing feature.
The feature only exists starting from
Arch Perfmon v4 (Skylake and newer).
@@ -3504,6 +3505,10 @@
before loading.
See Documentation/blockdev/ramdisk.txt.
+ psi= [KNL] Enable or disable pressure stall information
+ tracking.
+ Format: <bool>
+
psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
probe for; one of (bare|imps|exps|lifebook|any).
psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
@@ -4194,9 +4199,13 @@
spectre_v2= [X86] Control mitigation of Spectre variant 2
(indirect branch speculation) vulnerability.
+ The default operation protects the kernel from
+ user space attacks.
- on - unconditionally enable
- off - unconditionally disable
+ on - unconditionally enable, implies
+ spectre_v2_user=on
+ off - unconditionally disable, implies
+ spectre_v2_user=off
auto - kernel detects whether your CPU model is
vulnerable
@@ -4206,6 +4215,12 @@
CONFIG_RETPOLINE configuration option, and the
compiler with which the kernel was built.
+ Selecting 'on' will also enable the mitigation
+ against user space to user space task attacks.
+
+ Selecting 'off' will disable both the kernel and
+ the user space protections.
+
Specific mitigations can also be selected manually:
retpoline - replace indirect branches
@@ -4215,6 +4230,48 @@
Not specifying this option is equivalent to
spectre_v2=auto.
+ spectre_v2_user=
+ [X86] Control mitigation of Spectre variant 2
+ (indirect branch speculation) vulnerability between
+ user space tasks
+
+ on - Unconditionally enable mitigations. Is
+ enforced by spectre_v2=on
+
+ off - Unconditionally disable mitigations. Is
+ enforced by spectre_v2=off
+
+ prctl - Indirect branch speculation is enabled,
+ but mitigation can be enabled via prctl
+ per thread. The mitigation control state
+ is inherited on fork.
+
+ prctl,ibpb
+ - Like "prctl" above, but only STIBP is
+ controlled per thread. IBPB is issued
+ always when switching between different user
+ space processes.
+
+ seccomp
+ - Same as "prctl" above, but all seccomp
+ threads will enable the mitigation unless
+ they explicitly opt out.
+
+ seccomp,ibpb
+ - Like "seccomp" above, but only STIBP is
+ controlled per thread. IBPB is issued
+ always when switching between different
+ user space processes.
+
+ auto - Kernel selects the mitigation depending on
+ the available CPU features and vulnerability.
+
+ Default mitigation:
+ If CONFIG_SECCOMP=y then "seccomp", otherwise "prctl"
+
+ Not specifying this option is equivalent to
+ spectre_v2_user=auto.
+
spec_store_bypass_disable=
[HW] Control Speculative Store Bypass (SSB) Disable mitigation
(Speculative Store Bypass vulnerability)
@@ -4713,6 +4770,8 @@
prevent spurious wakeup);
n = USB_QUIRK_DELAY_CTRL_MSG (Device needs a
pause after every control message);
+ o = USB_QUIRK_HUB_SLOW_RESET (Hub needs extra
+ delay after resetting its port);
Example: quirks=0781:5580:bk,0a5c:5834:gij
usbhid.mousepoll=
diff --git a/Documentation/admin-guide/security-bugs.rst b/Documentation/admin-guide/security-bugs.rst
index 164bf71149fd..30187d49dc2c 100644
--- a/Documentation/admin-guide/security-bugs.rst
+++ b/Documentation/admin-guide/security-bugs.rst
@@ -32,16 +32,17 @@ Disclosure and embargoed information
The security list is not a disclosure channel. For that, see Coordination
below.
-Once a robust fix has been developed, our preference is to release the
-fix in a timely fashion, treating it no differently than any of the other
-thousands of changes and fixes the Linux kernel project releases every
-month.
-
-However, at the request of the reporter, we will postpone releasing the
-fix for up to 5 business days after the date of the report or after the
-embargo has lifted; whichever comes first. The only exception to that
-rule is if the bug is publicly known, in which case the preference is to
-release the fix as soon as it's available.
+Once a robust fix has been developed, the release process starts. Fixes
+for publicly known bugs are released immediately.
+
+Although our preference is to release fixes for publicly undisclosed bugs
+as soon as they become available, this may be postponed at the request of
+the reporter or an affected party for up to 7 calendar days from the start
+of the release process, with an exceptional extension to 14 calendar days
+if it is agreed that the criticality of the bug requires more time. The
+only valid reason for deferring the publication of a fix is to accommodate
+the logistics of QA and large scale rollouts which require release
+coordination.
Whilst embargoed information may be shared with trusted individuals in
order to develop a fix, such information will not be published alongside
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