Merge "Merge android-4.14.158 (84afceb) into msm-4.14" (2cf5a3b8) · Commits · e / devices / android_kernel_xiaomi_sm6125

Documentation/admin-guide/hw-vuln/mds.rst

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		@@ -265,8 +265,11 @@ time with the option "mds=". The valid arguments for this option are:

		============ =============================================================

		Not specifying this option is equivalent to "mds=full".

		Not specifying this option is equivalent to "mds=full". For processors
		that are affected by both TAA (TSX Asynchronous Abort) and MDS,
		specifying just "mds=off" without an accompanying "tsx_async_abort=off"
		will have no effect as the same mitigation is used for both
		vulnerabilities.

		Mitigation selection guide
		--------------------------

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		@@ -174,7 +174,10 @@ the option "tsx_async_abort=". The valid arguments for this option are:
		CPU is not vulnerable to cross-thread TAA attacks.
		============ =============================================================

		Not specifying this option is equivalent to "tsx_async_abort=full".
		Not specifying this option is equivalent to "tsx_async_abort=full". For
		processors that are affected by both TAA and MDS, specifying just
		"tsx_async_abort=off" without an accompanying "mds=off" will have no
		effect as the same mitigation is used for both vulnerabilities.

		The kernel command line also allows to control the TSX feature using the
		parameter "tsx=" on CPUs which support TSX control. MSR_IA32_TSX_CTRL is used

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		@@ -2276,6 +2276,12 @@
		SMT on vulnerable CPUs
		off - Unconditionally disable MDS mitigation

		On TAA-affected machines, mds=off can be prevented by
		an active TAA mitigation as both vulnerabilities are
		mitigated with the same mechanism so in order to disable
		this mitigation, you need to specify tsx_async_abort=off
		too.

		Not specifying this option is equivalent to
		mds=full.

		@@ -4625,6 +4631,11 @@
		vulnerable to cross-thread TAA attacks.
		off - Unconditionally disable TAA mitigation

		On MDS-affected machines, tsx_async_abort=off can be
		prevented by an active MDS mitigation as both vulnerabilities
		are mitigated with the same mechanism so in order to disable
		this mitigation, you need to specify mds=off too.

		Not specifying this option is equivalent to
		tsx_async_abort=full. On CPUs which are MDS affected
		and deploy MDS mitigation, TAA mitigation is not

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		@@ -100,6 +100,16 @@ its hardware characteristcs.

		* Optional properties for all components:
		* reg-names: names corresponding to each reg property value.

		* Optional properties for all components:

		* arm,coresight-loses-context-with-cpu : boolean. Indicates that the
		hardware will lose register context on CPU power down (e.g. CPUIdle).
		An example of where this may be needed are systems which contain a
		coresight component and CPU in the same power domain. When the CPU
		powers down the coresight component also powers down and loses its
		context. This property is currently only used for the ETM 4.x driver.

		* Optional properties for ETM/PTMs:

		* arm,cp14: must be present if the system accesses ETM/PTM management

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		@@ -160,7 +160,7 @@ them but you should handle them according to your needs.
		UHID_OUTPUT:
		This is sent if the HID device driver wants to send raw data to the I/O
		device on the interrupt channel. You should read the payload and forward it to
		the device. The payload is of type "struct uhid_data_req".
		the device. The payload is of type "struct uhid_output_req".
		This may be received even though you haven't received UHID_OPEN, yet.

		UHID_GET_REPORT: