Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net (675f176b) · Commits · EulixOS / Software / Kernel

.mailmap

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		@@ -25,6 +25,8 @@ Aleksey Gorelov <aleksey_gorelov@phoenix.com>
		Alexander Lobakin <alobakin@pm.me> <alobakin@dlink.ru>
		Alexander Lobakin <alobakin@pm.me> <alobakin@marvell.com>
		Alexander Lobakin <alobakin@pm.me> <bloodyreaper@yandex.ru>
		Alexander Mikhalitsyn <alexander@mihalicyn.com> <alexander.mikhalitsyn@virtuozzo.com>
		Alexander Mikhalitsyn <alexander@mihalicyn.com> <aleksandr.mikhalitsyn@canonical.com>
		Alexandre Belloni <alexandre.belloni@bootlin.com> <alexandre.belloni@free-electrons.com>
		Alexei Starovoitov <ast@kernel.org> <alexei.starovoitov@gmail.com>
		Alexei Starovoitov <ast@kernel.org> <ast@fb.com>

Documentation/admin-guide/hw-vuln/cross-thread-rsb.rst

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		.. SPDX-License-Identifier: GPL-2.0

		Cross-Thread Return Address Predictions
		=======================================

		Certain AMD and Hygon processors are subject to a cross-thread return address
		predictions vulnerability. When running in SMT mode and one sibling thread
		transitions out of C0 state, the other sibling thread could use return target
		predictions from the sibling thread that transitioned out of C0.

		The Spectre v2 mitigations protect the Linux kernel, as it fills the return
		address prediction entries with safe targets when context switching to the idle
		thread. However, KVM does allow a VMM to prevent exiting guest mode when
		transitioning out of C0. This could result in a guest-controlled return target
		being consumed by the sibling thread.

		Affected processors
		-------------------

		The following CPUs are vulnerable:

		- AMD Family 17h processors
		- Hygon Family 18h processors

		Related CVEs
		------------

		The following CVE entry is related to this issue:

		============== =======================================
		CVE-2022-27672 Cross-Thread Return Address Predictions
		============== =======================================

		Problem
		-------

		Affected SMT-capable processors support 1T and 2T modes of execution when SMT
		is enabled. In 2T mode, both threads in a core are executing code. For the
		processor core to enter 1T mode, it is required that one of the threads
		requests to transition out of the C0 state. This can be communicated with the
		HLT instruction or with an MWAIT instruction that requests non-C0.
		When the thread re-enters the C0 state, the processor transitions back
		to 2T mode, assuming the other thread is also still in C0 state.

		In affected processors, the return address predictor (RAP) is partitioned
		depending on the SMT mode. For instance, in 2T mode each thread uses a private
		16-entry RAP, but in 1T mode, the active thread uses a 32-entry RAP. Upon
		transition between 1T/2T mode, the RAP contents are not modified but the RAP
		pointers (which control the next return target to use for predictions) may
		change. This behavior may result in return targets from one SMT thread being
		used by RET predictions in the sibling thread following a 1T/2T switch. In
		particular, a RET instruction executed immediately after a transition to 1T may
		use a return target from the thread that just became idle. In theory, this
		could lead to information disclosure if the return targets used do not come
		from trustworthy code.

		Attack scenarios
		----------------

		An attack can be mounted on affected processors by performing a series of CALL
		instructions with targeted return locations and then transitioning out of C0
		state.

		Mitigation mechanism
		--------------------

		Before entering idle state, the kernel context switches to the idle thread. The
		context switch fills the RAP entries (referred to as the RSB in Linux) with safe
		targets by performing a sequence of CALL instructions.

		Prevent a guest VM from directly putting the processor into an idle state by
		intercepting HLT and MWAIT instructions.

		Both mitigations are required to fully address this issue.

		Mitigation control on the kernel command line
		---------------------------------------------

		Use existing Spectre v2 mitigations that will fill the RSB on context switch.

		Mitigation control for KVM - module parameter
		---------------------------------------------

		By default, the KVM hypervisor mitigates this issue by intercepting guest
		attempts to transition out of C0. A VMM can use the KVM_CAP_X86_DISABLE_EXITS
		capability to override those interceptions, but since this is not common, the
		mitigation that covers this path is not enabled by default.

		The mitigation for the KVM_CAP_X86_DISABLE_EXITS capability can be turned on
		using the boolean module parameter mitigate_smt_rsb, e.g.:
		kvm.mitigate_smt_rsb=1

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

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		@@ -18,3 +18,4 @@ are configurable at compile, boot or run time.
		core-scheduling.rst
		l1d_flush.rst
		processor_mmio_stale_data.rst
		cross-thread-rsb.rst

MAINTAINERS

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		@@ -16135,7 +16135,7 @@ F: drivers/pci/controller/pci-v3-semi.c

		PCI ENDPOINT SUBSYSTEM
		M: Lorenzo Pieralisi <lpieralisi@kernel.org>
		R: Krzysztof Wilczyński <kw@linux.com>
		M: Krzysztof Wilczyński <kw@linux.com>
		R: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
		R: Kishon Vijay Abraham I <kishon@kernel.org>
		L: linux-pci@vger.kernel.org
		@@ -16143,7 +16143,7 @@ S: Supported
		Q: https://patchwork.kernel.org/project/linux-pci/list/
		B: https://bugzilla.kernel.org
		C: irc://irc.oftc.net/linux-pci
		T: git git://git.kernel.org/pub/scm/linux/kernel/git/lpieralisi/pci.git
		T: git git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git
		F: Documentation/PCI/endpoint/*
		F: Documentation/misc-devices/pci-endpoint-test.rst
		F: drivers/misc/pci_endpoint_test.c
		@@ -16178,7 +16178,7 @@ S: Supported
		Q: https://patchwork.kernel.org/project/linux-pci/list/
		B: https://bugzilla.kernel.org
		C: irc://irc.oftc.net/linux-pci
		T: git git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git
		T: git git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git
		F: Documentation/driver-api/pci/p2pdma.rst
		F: drivers/pci/p2pdma.c
		F: include/linux/pci-p2pdma.h
		@@ -16200,14 +16200,14 @@ F: drivers/pci/controller/pci-xgene-msi.c

		PCI NATIVE HOST BRIDGE AND ENDPOINT DRIVERS
		M: Lorenzo Pieralisi <lpieralisi@kernel.org>
		M: Krzysztof Wilczyński <kw@linux.com>
		R: Rob Herring <robh@kernel.org>
		R: Krzysztof Wilczyński <kw@linux.com>
		L: linux-pci@vger.kernel.org
		S: Supported
		Q: https://patchwork.kernel.org/project/linux-pci/list/
		B: https://bugzilla.kernel.org
		C: irc://irc.oftc.net/linux-pci
		T: git git://git.kernel.org/pub/scm/linux/kernel/git/lpieralisi/pci.git
		T: git git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git
		F: Documentation/devicetree/bindings/pci/
		F: drivers/pci/controller/
		F: drivers/pci/pci-bridge-emul.c
		@@ -16220,7 +16220,7 @@ S: Supported
		Q: https://patchwork.kernel.org/project/linux-pci/list/
		B: https://bugzilla.kernel.org
		C: irc://irc.oftc.net/linux-pci
		T: git git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git
		T: git git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git
		F: Documentation/PCI/
		F: Documentation/devicetree/bindings/pci/
		F: arch/x86/kernel/early-quirks.c
		@@ -20120,6 +20120,7 @@ F: drivers/watchdog/sunplus_wdt.c
		SUPERH
		M: Yoshinori Sato <ysato@users.sourceforge.jp>
		M: Rich Felker <dalias@libc.org>
		M: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
		L: linux-sh@vger.kernel.org
		S: Maintained
		Q: http://patchwork.kernel.org/project/linux-sh/list/
		@@ -20352,8 +20353,7 @@ S: Maintained
		F: drivers/platform/x86/system76_acpi.c

		SYSV FILESYSTEM
		M: Christoph Hellwig <hch@infradead.org>
		S: Maintained
		S: Orphan
		F: Documentation/filesystems/sysv-fs.rst
		F: fs/sysv/
		F: include/linux/sysv_fs.h
		@@ -21848,11 +21848,9 @@ W: http://en.wikipedia.org/wiki/Util-linux
		T: git git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git

		UUID HELPERS
		M: Christoph Hellwig <hch@lst.de>
		R: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
		L: linux-kernel@vger.kernel.org
		S: Maintained
		T: git git://git.infradead.org/users/hch/uuid.git
		F: include/linux/uuid.h
		F: include/uapi/linux/uuid.h
		F: lib/test_uuid.c

Makefile

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		@@ -2,7 +2,7 @@
		VERSION = 6
		PATCHLEVEL = 2
		SUBLEVEL = 0
		EXTRAVERSION = -rc7
		EXTRAVERSION = -rc8
		NAME = Hurr durr I'ma ninja sloth

		# DOCUMENTATION