Daniel Sneddon e35c657943 x86/speculation: Add force option to GDS mitigation ... commit 553a5c03e90a6087e88f8ff878335ef0621536fb upstream The Gather Data Sampling (GDS) vulnerability allows malicious software to infer stale data previously stored in vector registers. This may include sensitive data such as cryptographic keys. GDS is mitigated in microcode, and systems with up-to-date microcode are protected by default. However, any affected system that is running with older microcode will still be vulnerable to GDS attacks. Since the gather instructions used by the attacker are part of the AVX2 and AVX512 extensions, disabling these extensions prevents gather instructions from being executed, thereby mitigating the system from GDS. Disabling AVX2 is sufficient, but we don't have the granularity to do this. The XCR0[2] disables AVX, with no option to just disable AVX2. Add a kernel parameter gather_data_sampling=force that will enable the microcode mitigation if available, otherwise it will disable AVX on affected systems. This option will be ignored if cmdline mitigations=off. This is a *big* hammer. It is known to break buggy userspace that uses incomplete, buggy AVX enumeration. Unfortunately, such userspace does exist in the wild: https://www.mail-archive.com/bug-coreutils@gnu.org/msg33046.html [ dhansen: add some more ominous warnings about disabling AVX ] Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2023-08-08 19:56:35 +02:00
..
ABI	x86/speculation: Add Gather Data Sampling mitigation	2023-08-08 19:56:35 +02:00
accounting	psi: Fix uaf issue when psi trigger is destroyed while being polled	2022-02-05 12:35:36 +01:00
admin-guide	x86/speculation: Add force option to GDS mitigation	2023-08-08 19:56:35 +02:00
arm	ARM: 9012/1: move device tree mapping out of linear region	2021-05-19 10:08:32 +02:00
arm64	arm64: errata: Remove AES hwcap for COMPAT tasks	2022-10-29 10:20:35 +02:00
block	docs: block: null_blk: enhance document style	2019-09-11 16:04:22 -06:00
bpf	bpf/flow_dissector: document flags	2019-07-25 18:00:41 -07:00
cdrom	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
core-api	XArray: add xas_split	2021-06-10 13:37:14 +02:00
cpu-freq	Documentation: cpufreq: Update policy notifier documentation	2019-09-02 22:44:05 +02:00
crypto	Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6	2019-09-18 12:11:14 -07:00
dev-tools	docs/scripts/gdb: add necessary make scripts_gdb step	2023-03-11 16:43:57 +01:00
devicetree	dt-bindings: rtc: sun6i-a31-rtc: Loosen the requirements on the clocks	2023-03-11 16:44:17 +01:00
doc-guide	docs: remove extra conf.py files	2019-07-17 06:57:52 -03:00
driver-api	spi: Update reference to struct spi_controller	2023-01-18 11:41:01 +01:00
EDID	docs: driver-api: add a series of orphaned documents	2019-07-15 11:03:02 -03:00
fault-injection	debugfs: fix error when writing negative value to atomic_t debugfs file	2023-01-18 11:40:56 +01:00
fb	fbdev: fix numbering of fbcon options	2020-02-24 08:36:42 +01:00
features	It's a somewhat calmer cycle for docs this time, as the churn of the mass	2019-09-17 16:22:26 -07:00
filesystems	fs: Lock moved directories	2023-07-27 08:37:26 +02:00
firmware_class
firmware-guide	Documentation: ACPI: EINJ: Fix obsolete example	2022-08-25 11:18:21 +02:00
fpga	Documentation: fpga: dfl: add descriptions for virtualization and new interfaces.	2019-09-03 19:35:42 -07:00
gpu	Merge drm/drm-next into drm-intel-next-queued	2019-08-22 00:10:36 -07:00
hid	docs: add some documentation dirs to the driver-api book	2019-07-15 11:03:02 -03:00
hwmon	Revert "hwmon: Make chip parameter for with_info API mandatory"	2022-06-25 12:44:36 +02:00
i2c	docs: i2c: convert to ReST and add to driver-api bookset	2019-07-31 13:25:27 -06:00
ia64	docs: add SPDX tags to new index files	2019-07-15 11:03:03 -03:00
ide	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
iio	docs: add some documentation dirs to the driver-api book	2019-07-15 11:03:02 -03:00
infiniband	Documentation/infiniband: update name of some functions	2019-09-13 16:55:55 -03:00
input	Input: iforce - add support for Boeder Force Feedback Wheel	2022-09-20 12:27:59 +02:00
ioctl	Remove DECnet support from kernel	2023-06-21 15:44:10 +02:00
isdn	docs: isdn: convert to ReST and add to kAPI bookset	2019-07-31 13:30:25 -06:00
kbuild	kbuild: support LLVM=1 to switch the default tools to Clang/LLVM	2020-08-26 10:40:47 +02:00
kernel-hacking	docs: Add documentation for Symbol Namespaces	2019-09-10 10:30:49 +02:00
leds	leds: core: Add support for composing LED class device names	2019-07-25 20:07:52 +02:00
livepatch	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
locking	doc🔒 remove reference to clever use of read-write lock	2019-09-14 01:53:27 -06:00
m68k	docs: README.buddha: convert to ReST and add to m68k book	2019-07-31 13:30:10 -06:00
maintainer	docs: Fix typo on pull requests guide	2019-08-12 15:14:14 -06:00
media	media: uapi: add MEDIA_BUS_FMT_METADATA_FIXED media bus format.	2023-05-17 11:35:36 +02:00
mic	docs: driver-api: add remaining converted dirs to it	2019-07-15 11:03:03 -03:00
mips	Main MIPS changes for v5.4:	2019-09-22 09:30:30 -07:00
misc-devices	Docs: misc: xilinx_sdfec: Add documentation	2019-08-15 17:54:38 +02:00
netlabel	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
networking	xsk: Honor SO_BINDTODEVICE on bind	2023-07-27 08:37:23 +02:00
nios2	docs: nios2: add it to the main Documentation body	2019-07-31 13:31:51 -06:00
openrisc	docs: openrisc: convert to ReST and add to documentation body	2019-07-31 13:30:20 -06:00
parisc	docs: parisc: convert to ReST and add to documentation body	2019-07-31 13:30:15 -06:00
PCI	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2019-08-27 14:23:31 -07:00
pcmcia	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
power	Merge branches 'pm-opp', 'pm-qos', 'acpi-pm', 'pm-domains' and 'pm-tools'	2019-09-17 09:49:19 +02:00
powerpc	docs: powerpc: Add missing documentation reference	2019-09-17 23:59:34 +10:00
process	docs: update mediator contact information in CoC doc	2022-11-25 17:42:20 +01:00
RCU	Merge branches 'consolidate.2019.08.01b', 'fixes.2019.08.12a', 'lists.2019.08.13a' and 'torture.2019.08.01b' into HEAD	2019-08-13 14:30:30 -07:00
riscv	It's a somewhat calmer cycle for docs this time, as the churn of the mass	2019-09-17 16:22:26 -07:00
s390	Documentation/s390: remove outdated debugging390 documentation	2019-08-21 12:41:43 +02:00
scheduler	sched/fair: Fix low cpu usage with high throttling by removing expiration of cpu-local slices	2019-08-08 09:09:30 +02:00
scsi	scsi: smartpqi: Update attribute name to driver_version	2020-01-17 19:48:27 +01:00
security	Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity	2019-09-27 19:37:27 -07:00
sh	docs: remove extra conf.py files	2019-07-17 06:57:52 -03:00
sound	ALSA: hda/sigmatel: add pin overrides for Intel DP45SG motherboard	2023-04-20 12:07:35 +02:00
sparc	docs: add arch doc directories to the index	2019-07-15 11:03:01 -03:00
sphinx	docs: Fix the docs build with Sphinx 6.0	2023-01-18 11:42:01 +01:00
sphinx-static
spi	spi: docs: convert to ReST and add it to the kABI bookset	2019-07-31 14:13:13 -06:00
target	tweewide: Fix most Shebang lines	2021-05-22 11:38:30 +02:00
timers	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
trace	tracing/histogram: Update document for KEYS_MAX size	2022-11-10 17:57:55 +01:00
translations	doc: arm64: fix grammar dtb placed in no attributes region	2019-09-06 08:44:34 -06:00
usb	USB: rio500: Remove Rio 500 kernel driver	2019-10-04 10:53:36 +02:00
userspace-api	Documentation: seccomp: Fix user notification documentation	2021-06-03 08:59:03 +02:00
virt	KVM: s390: disable migration mode when dirty tracking is disabled	2023-03-11 16:44:01 +01:00
virtual	cpuidle: add haltpoll governor	2019-07-30 17:27:37 +02:00
vm	arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL	2022-05-15 19:54:46 +02:00
w1	docs: w1: convert to ReST and add to the kAPI group of docs	2019-07-31 14:16:17 -06:00
watchdog	linux-watchdog 5.4-rc1 tag	2019-09-27 11:17:38 -07:00
x86	x86/CPU/AMD: Save AMD NodeId as cpu_die_id	2020-12-30 11:51:47 +01:00
xtensa	xtensa: fix TLBTEMP area placement	2020-11-24 13:29:22 +01:00
.gitignore
asm-annotations.rst	linkage: Introduce new macros for assembler symbols	2020-11-10 12:37:24 +01:00
atomic_bitops.txt	locking/atomic: Make test_and_*_bit() ordered on failure	2022-08-25 11:18:31 +02:00
atomic_t.txt	Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2019-07-08 16:12:03 -07:00
bus-virt-phys-mapping.txt
Changes
CodingStyle
conf.py	docs/conf.py: Cope with removal of language=None in Sphinx 5.0.0	2022-06-14 18:11:49 +02:00
COPYING-logo	docs: logo.txt: rename it to COPYING-logo	2019-07-15 09:20:27 -03:00
crc32.txt
debugging-modules.txt
debugging-via-ohci1394.txt
digsig.txt
DMA-API-HOWTO.txt	docs: DMA-API-HOWTO.txt: fix an unmarked code block	2019-07-15 09:20:24 -03:00
DMA-API.txt	dma-mapping: remove dma_release_declared_memory	2019-09-04 11:13:19 +02:00
DMA-attributes.txt	Reinstate some of "swiotlb: rework "fix info leak with DMA_FROM_DEVICE""	2022-05-25 09:14:38 +02:00
DMA-ISA-LPC.txt
docutils.conf	doc-rst: Add missing newline at end of file	2019-06-20 14:16:56 -06:00
dontdiff	kbuild: create *.mod with full directory path and remove MODVERDIR	2019-07-18 02:19:31 +09:00
futex-requeue-pi.txt
hwspinlock.txt	hwspinlock: add the 'in_atomic' API	2019-06-29 21:08:14 -07:00
index.rst	linkage: Introduce new macros for assembler symbols	2020-11-10 12:37:24 +01:00
io_ordering.txt
io-mapping.txt
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt
IRQ.txt
irqflags-tracing.txt
Kconfig	docs: Kbuild/Makefile: allow check for missing docs at build time	2019-06-07 11:33:16 -06:00
kobject.txt
kprobes.txt
kref.txt
logo.gif
lzo.txt	lib/lzo: fix ambiguous encoding bug in lzo-rle	2020-06-17 16:40:28 +02:00
mailbox.txt
Makefile	docs: Kbuild/Makefile: allow check for missing docs at build time	2019-06-07 11:33:16 -06:00
memory-barriers.txt	docs: fix broken doc references due to renames	2019-07-17 06:57:51 -03:00
nommu-mmap.txt
padata.txt	padata: allocate workqueue internally	2019-09-13 21:15:39 +10:00
percpu-rw-semaphore.txt
pi-futex.txt	docs: locking: convert docs to ReST and rename to *.rst	2019-07-15 08:53:27 -03:00
preempt-locking.txt
rbtree.txt	docs: rbtree.txt: fix Sphinx build warnings	2019-07-15 09:20:24 -03:00
remoteproc.txt	remoteproc: add vendor resources handling	2019-06-29 12:02:17 -07:00
robust-futex-ABI.txt
robust-futexes.txt
rpmsg.txt
speculation.txt
static-keys.txt
SubmittingPatches
tee.txt	Documentation: tee: Grammar s/the its/its/	2019-06-07 11:23:38 -06:00
this_cpu_ops.txt
unaligned-memory-access.txt
xz.txt