Merge branch 'linus' into perf/urgent, to synchronize with upstream (fdff7c21) · Commits · 戴 / test

.mailmap

+5 −0

Original line number	Diff line number	Diff line
		@@ -139,6 +139,7 @@ Juha Yrjola <at solidboot.com>
		Juha Yrjola <juha.yrjola@nokia.com>
		Juha Yrjola <juha.yrjola@solidboot.com>
		Julien Thierry <julien.thierry.kdev@gmail.com> <julien.thierry@arm.com>
		Kamil Konieczny <k.konieczny@samsung.com> <k.konieczny@partner.samsung.com>
		Kay Sievers <kay.sievers@vrfy.org>
		Kenneth W Chen <kenneth.w.chen@intel.com>
		Konstantin Khlebnikov <koct9i@gmail.com> <k.khlebnikov@samsung.com>
		@@ -210,6 +211,10 @@ Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
		Patrick Mochel <mochel@digitalimplant.org>
		Paul Burton <paulburton@kernel.org> <paul.burton@imgtec.com>
		Paul Burton <paulburton@kernel.org> <paul.burton@mips.com>
		Paul E. McKenney <paulmck@kernel.org> <paulmck@linux.ibm.com>
		Paul E. McKenney <paulmck@kernel.org> <paulmck@linux.vnet.ibm.com>
		Paul E. McKenney <paulmck@kernel.org> <paul.mckenney@linaro.org>
		Paul E. McKenney <paulmck@kernel.org> <paulmck@us.ibm.com>
		Peter A Jonsson <pj@ludd.ltu.se>
		Peter Oruba <peter@oruba.de>
		Peter Oruba <peter.oruba@amd.com>

Documentation/ABI/testing/ima_policy

+14 −2

Original line number	Diff line number	Diff line
		@@ -25,11 +25,11 @@ Description:
		lsm: [[subj_user=] [subj_role=] [subj_type=]
		[obj_user=] [obj_role=] [obj_type=]]
		option: [[appraise_type=]] [template=] [permit_directio]
		[appraise_flag=]
		[appraise_flag=] [keyrings=]
		base: func:= [BPRM_CHECK][MMAP_CHECK][CREDS_CHECK][FILE_CHECK][MODULE_CHECK]
		[FIRMWARE_CHECK]
		[KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK]
		[KEXEC_CMDLINE]
		[KEXEC_CMDLINE] [KEY_CHECK]
		mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND]
		[[^]MAY_EXEC]
		fsmagic:= hex value
		@@ -42,6 +42,9 @@ Description:
		appraise_flag:= [check_blacklist]
		Currently, blacklist check is only for files signed with appended
		signature.
		keyrings:= list of keyrings
		(eg, .builtin_trusted_keys\|.ima). Only valid
		when action is "measure" and func is KEY_CHECK.
		template:= name of a defined IMA template type
		(eg, ima-ng). Only valid when action is "measure".
		pcr:= decimal value
		@@ -113,3 +116,12 @@ Description:
		Example of appraise rule allowing modsig appended signatures:

		appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig\|modsig

		Example of measure rule using KEY_CHECK to measure all keys:

		measure func=KEY_CHECK

		Example of measure rule using KEY_CHECK to only measure
		keys added to .builtin_trusted_keys or .ima keyring:

		measure func=KEY_CHECK keyrings=.builtin_trusted_keys\|.ima

Documentation/ABI/testing/sysfs-bus-mdio

0 → 100644

+63 −0

Original line number	Diff line number	Diff line
		What: /sys/bus/mdio_bus/devices/.../statistics/
		Date: January 2020
		KernelVersion: 5.6
		Contact: netdev@vger.kernel.org
		Description:
		This folder contains statistics about global and per
		MDIO bus address statistics.

		What: /sys/bus/mdio_bus/devices/.../statistics/transfers
		Date: January 2020
		KernelVersion: 5.6
		Contact: netdev@vger.kernel.org
		Description:
		Total number of transfers for this MDIO bus.

		What: /sys/bus/mdio_bus/devices/.../statistics/errors
		Date: January 2020
		KernelVersion: 5.6
		Contact: netdev@vger.kernel.org
		Description:
		Total number of transfer errors for this MDIO bus.

		What: /sys/bus/mdio_bus/devices/.../statistics/writes
		Date: January 2020
		KernelVersion: 5.6
		Contact: netdev@vger.kernel.org
		Description:
		Total number of write transactions for this MDIO bus.

		What: /sys/bus/mdio_bus/devices/.../statistics/reads
		Date: January 2020
		KernelVersion: 5.6
		Contact: netdev@vger.kernel.org
		Description:
		Total number of read transactions for this MDIO bus.

		What: /sys/bus/mdio_bus/devices/.../statistics/transfers_<addr>
		Date: January 2020
		KernelVersion: 5.6
		Contact: netdev@vger.kernel.org
		Description:
		Total number of transfers for this MDIO bus address.

		What: /sys/bus/mdio_bus/devices/.../statistics/errors_<addr>
		Date: January 2020
		KernelVersion: 5.6
		Contact: netdev@vger.kernel.org
		Description:
		Total number of transfer errors for this MDIO bus address.

		What: /sys/bus/mdio_bus/devices/.../statistics/writes_<addr>
		Date: January 2020
		KernelVersion: 5.6
		Contact: netdev@vger.kernel.org
		Description:
		Total number of write transactions for this MDIO bus address.

		What: /sys/bus/mdio_bus/devices/.../statistics/reads_<addr>
		Date: January 2020
		KernelVersion: 5.6
		Contact: netdev@vger.kernel.org
		Description:
		Total number of read transactions for this MDIO bus address.

Documentation/RCU/NMI-RCU.txt→Documentation/RCU/NMI-RCU.rst

+28 −25

Original line number	Diff line number	Diff line
		.. _NMI_rcu_doc:

		Using RCU to Protect Dynamic NMI Handlers
		=========================================


		Although RCU is usually used to protect read-mostly data structures,
		@@ -9,7 +12,7 @@ work in "arch/x86/oprofile/nmi_timer_int.c" and in
		"arch/x86/kernel/traps.c".

		The relevant pieces of code are listed below, each followed by a
		brief explanation.
		brief explanation::

		static int dummy_nmi_callback(struct pt_regs *regs, int cpu)
		{
		@@ -18,12 +21,12 @@ brief explanation.

		The dummy_nmi_callback() function is a "dummy" NMI handler that does
		nothing, but returns zero, thus saying that it did nothing, allowing
		the NMI handler to take the default machine-specific action.
		the NMI handler to take the default machine-specific action::

		static nmi_callback_t nmi_callback = dummy_nmi_callback;

		This nmi_callback variable is a global function pointer to the current
		NMI handler.
		NMI handler::

		void do_nmi(struct pt_regs * regs, long error_code)
		{
		@@ -53,11 +56,12 @@ anyway. However, in practice it is a good documentation aid, particularly
		for anyone attempting to do something similar on Alpha or on systems
		with aggressive optimizing compilers.

		Quick Quiz: Why might the rcu_dereference_sched() be necessary on Alpha,
		given that the code referenced by the pointer is read-only?
		Quick Quiz:
		Why might the rcu_dereference_sched() be necessary on Alpha, given that the code referenced by the pointer is read-only?

		:ref:`Answer to Quick Quiz <answer_quick_quiz_NMI>`

		Back to the discussion of NMI and RCU...
		Back to the discussion of NMI and RCU::

		void set_nmi_callback(nmi_callback_t callback)
		{
		@@ -68,7 +72,7 @@ The set_nmi_callback() function registers an NMI handler. Note that any
		data that is to be used by the callback must be initialized up -before-
		the call to set_nmi_callback(). On architectures that do not order
		writes, the rcu_assign_pointer() ensures that the NMI handler sees the
		initialized values.
		initialized values::

		void unset_nmi_callback(void)
		{
		@@ -82,7 +86,7 @@ up any data structures used by the old NMI handler until execution
		of it completes on all other CPUs.

		One way to accomplish this is via synchronize_rcu(), perhaps as
		follows:
		follows::

		unset_nmi_callback();
		synchronize_rcu();
		@@ -98,13 +102,12 @@ to free up the handler's data as soon as synchronize_rcu() returns.
		Important note: for this to work, the architecture in question must
		invoke nmi_enter() and nmi_exit() on NMI entry and exit, respectively.

		.. _answer_quick_quiz_NMI:

		Answer to Quick Quiz

		Why might the rcu_dereference_sched() be necessary on Alpha, given
		that the code referenced by the pointer is read-only?
		Answer to Quick Quiz:
		Why might the rcu_dereference_sched() be necessary on Alpha, given that the code referenced by the pointer is read-only?

		Answer: The caller to set_nmi_callback() might well have
		The caller to set_nmi_callback() might well have
		initialized some data that is to be used by the new NMI
		handler. In this case, the rcu_dereference_sched() would
		be needed, because otherwise a CPU that received an NMI

Documentation/RCU/arrayRCU.txt→Documentation/RCU/arrayRCU.rst

+23 −11

Original line number	Diff line number	Diff line
		Using RCU to Protect Read-Mostly Arrays
		.. _array_rcu_doc:

		Using RCU to Protect Read-Mostly Arrays
		=======================================

		Although RCU is more commonly used to protect linked lists, it can
		also be used to protect arrays. Three situations are as follows:

		1. Hash Tables
		1. :ref:`Hash Tables <hash_tables>`

		2. Static Arrays
		2. :ref:`Static Arrays <static_arrays>`

		3. Resizeable Arrays
		3. :ref:`Resizable Arrays <resizable_arrays>`

		Each of these three situations involves an RCU-protected pointer to an
		array that is separately indexed. It might be tempting to consider use
		of RCU to instead protect the index into an array, however, this use
		case is -not- supported. The problem with RCU-protected indexes into
		case is not supported. The problem with RCU-protected indexes into
		arrays is that compilers can play way too many optimization games with
		integers, which means that the rules governing handling of these indexes
		are far more trouble than they are worth. If RCU-protected indexes into
		@@ -24,16 +26,20 @@ to be safely used.
		That aside, each of the three RCU-protected pointer situations are
		described in the following sections.

		.. _hash_tables:

		Situation 1: Hash Tables
		------------------------

		Hash tables are often implemented as an array, where each array entry
		has a linked-list hash chain. Each hash chain can be protected by RCU
		as described in the listRCU.txt document. This approach also applies
		to other array-of-list situations, such as radix trees.

		.. _static_arrays:

		Situation 2: Static Arrays
		--------------------------

		Static arrays, where the data (rather than a pointer to the data) is
		located in each array element, and where the array is never resized,
		@@ -41,13 +47,17 @@ have not been used with RCU. Rik van Riel recommends using seqlock in
		this situation, which would also have minimal read-side overhead as long
		as updates are rare.

		Quick Quiz: Why is it so important that updates be rare when
		using seqlock?
		Quick Quiz:
		Why is it so important that updates be rare when using seqlock?

		:ref:`Answer to Quick Quiz <answer_quick_quiz_seqlock>`

		.. _resizable_arrays:

		Situation 3: Resizeable Arrays
		Situation 3: Resizable Arrays
		------------------------------

		Use of RCU for resizeable arrays is demonstrated by the grow_ary()
		Use of RCU for resizable arrays is demonstrated by the grow_ary()
		function formerly used by the System V IPC code. The array is used
		to map from semaphore, message-queue, and shared-memory IDs to the data
		structure that represents the corresponding IPC construct. The grow_ary()
		@@ -60,7 +70,7 @@ the remainder of the new, updates the ids->entries pointer to point to
		the new array, and invokes ipc_rcu_putref() to free up the old array.
		Note that rcu_assign_pointer() is used to update the ids->entries pointer,
		which includes any memory barriers required on whatever architecture
		you are running on.
		you are running on::

		static int grow_ary(struct ipc_ids* ids, int newsize)
		{
		@@ -112,7 +122,7 @@ a simple check suffices. The pointer to the structure corresponding
		to the desired IPC object is placed in "out", with NULL indicating
		a non-existent entry. After acquiring "out->lock", the "out->deleted"
		flag indicates whether the IPC object is in the process of being
		deleted, and, if not, the pointer is returned.
		deleted, and, if not, the pointer is returned::

		struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id)
		{
		@@ -144,8 +154,10 @@ deleted, and, if not, the pointer is returned.
		return out;
		}

		.. _answer_quick_quiz_seqlock:

		Answer to Quick Quiz:
		Why is it so important that updates be rare when using seqlock?

		The reason that it is important that updates be rare when
		using seqlock is that frequent updates can livelock readers.

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