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Tom Lendacky 9272c25734 x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h 
[ Upstream commit c49a0a8013 ]

There have been reports of RDRAND issues after resuming from suspend on
some AMD family 15h and family 16h systems. This issue stems from a BIOS
not performing the proper steps during resume to ensure RDRAND continues
to function properly.

RDRAND support is indicated by CPUID Fn00000001_ECX[30]. This bit can be
reset by clearing MSR C001_1004[62]. Any software that checks for RDRAND
support using CPUID, including the kernel, will believe that RDRAND is
not supported.

Update the CPU initialization to clear the RDRAND CPUID bit for any family
15h and 16h processor that supports RDRAND. If it is known that the family
15h or family 16h system does not have an RDRAND resume issue or that the
system will not be placed in suspend, the "rdrand=force" kernel parameter
can be used to stop the clearing of the RDRAND CPUID bit.

Additionally, update the suspend and resume path to save and restore the
MSR C001_1004 value to ensure that the RDRAND CPUID setting remains in
place after resuming from suspend.

Note, that clearing the RDRAND CPUID bit does not prevent a processor
that normally supports the RDRAND instruction from executing it. So any
code that determined the support based on family and model won't #UD.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chen Yu <yu.c.chen@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: "linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>
Cc: "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: <stable@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "x86@kernel.org" <x86@kernel.org>
Link: https://lkml.kernel.org/r/7543af91666f491547bd86cebb1e17c66824ab9f.1566229943.git.thomas.lendacky@amd.com
[sl: adjust context in docs]
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-06 10:19:41 +02:00
..
80211
docs-rst: sphinxify 802.11 documentation
2016-10-11 16:19:17 -06:00
ABI
Documentation: Add MDS vulnerability documentation
2019-05-14 19:19:41 +02:00
accounting
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acpi
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aoe
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arm
ARM: 8833/1: Ensure that NEON code always compiles with Clang
2019-04-05 22:29:11 +02:00
arm64
arm64: Add work around for Arm Cortex-A55 Erratum 1024718
2018-05-16 10:08:42 +02:00
auxdisplay
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backlight
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blackfin
samples: move blackfin gptimers-example from Documentation
2016-10-10 07:12:02 -06:00
block
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blockdev
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bus-devices
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cdrom
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cgroup-v1
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cma
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connector
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console
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cpu-freq
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cpuidle
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cris
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crypto
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dev-tools
mm: kmemleak: avoid using __va() on addresses that don't have a lowmem mapping
2016-10-11 15:06:33 -07:00
development-process
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device-mapper
dm thin: fix documentation relative to low water mark threshold
2018-05-30 07:50:20 +02:00
devicetree
arm64: dts: marvell: Fix A37xx UART0 register size
2019-08-04 09:33:44 +02:00
dmaengine
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DocBook
Merge tag 'docs-4.9-2' of git://git.lwn.net/linux
2016-10-14 14:11:22 -07:00
driver-api
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driver-model
Merge tag 'for-v4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply
2016-10-06 18:21:15 -07:00
early-userspace
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EDID
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extcon
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fault-injection
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fb
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features
Documentation: MIPS supports HAVE_REGS_AND_STACK_ACCESS_API
2016-10-13 17:19:19 +02:00
filesystems
mm, proc: be more verbose about unstable VMA flags in /proc/<pid>/smaps
2019-01-26 09:38:36 +01:00
firmware_class
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fmc
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fpga
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frv
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gpio
gpio/board.txt: point to gpiod_set_value
2016-10-20 14:14:11 +02:00
gpu
Merge tag 'drm-for-v4.9' of git://people.freedesktop.org/~airlied/linux
2016-10-11 18:12:22 -07:00
hid
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hw-vuln
Documentation: Correct the possible MDS sysfs values
2019-05-14 19:19:42 +02:00
hwmon
hwmon: (ina2xx) fix sysfs shunt resistor read access
2018-10-03 17:01:52 -07:00
i2c
i2c: Documentation: i2c-topology: fix minor whitespace nit
2016-11-10 21:18:56 +01:00
ia64
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ide
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iio
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infiniband
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input
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ioctl
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isdn
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ja_JP
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kbuild
Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
2016-10-14 14:26:58 -07:00
kdump
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ko_KR
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laptops
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leds
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livepatch
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locking
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m68k
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media
videodev2.h: go back to limited range Y'CbCr for SRGB and, ADOBERGB
2017-02-23 17:44:37 +01:00
memory-devices
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metag
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mic
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mips
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misc-devices
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mmc
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mn10300
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mtd
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namespaces
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netlabel
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networking
tcp: add tcp_min_snd_mss sysctl
2019-06-17 19:53:33 +02:00
nfc
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nios2
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nvdimm
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nvmem
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parisc
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PCI
Merge tag 'pci-v4.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
2016-10-07 11:46:37 -07:00
pcmcia
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perf
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phy
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platform
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power
Merge tag 'for-v4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply
2016-10-06 18:21:15 -07:00
powerpc
Merge tag 'powerpc-4.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
2016-10-07 20:19:31 -07:00
pps
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prctl
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pti
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ptp
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rapidio
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RCU
kthread: kthread worker API cleanup
2016-10-11 15:06:33 -07:00
s390
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scheduler
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scsi
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security
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serial
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sh
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sound
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sphinx
docs: sphinx-extensions: make rstFlatTable work with docutils 0.13
2017-01-09 08:32:18 +01:00
sphinx-static
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spi
Doc: update 00-INDEX files to reflect the runnable code move
2016-10-10 07:12:09 -06:00
sysctl
bpf: add bpf_jit_limit knob to restrict unpriv allocations
2019-08-25 10:51:41 +02:00
target
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thermal
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timers
Doc: update 00-INDEX files to reflect the runnable code move
2016-10-10 07:12:09 -06:00
tpm
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trace
Merge tag 'trace-v4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
2016-10-06 11:48:41 -07:00
usb
USB: core: Fix bug caused by duplicate interface PM usage counter
2019-05-08 07:19:08 +02:00
virtual
KVM: Reject device ioctls from processes other than the VM's creator
2019-04-03 06:24:19 +02:00
vm
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w1
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watchdog
Merge tag 'linux-kselftest-4.9-rc1-update' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
2016-10-14 15:17:12 -07:00
wimax
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x86
x86/speculation/mds: Improve CPU buffer clear documentation
2019-05-21 18:48:56 +02:00
xtensa
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zh_CN
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.gitignore
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00-INDEX
Doc: update 00-INDEX files to reflect the runnable code move
2016-10-10 07:12:09 -06:00
adding-syscalls.txt
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applying-patches.txt
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assoc_array.txt
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atomic_ops.txt
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bad_memory.txt
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basic_profiling.txt
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bcache.txt
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binfmt_misc.txt
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braille-console.txt
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bt8xxgpio.txt
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btmrvl.txt
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BUG-HUNTING
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bus-virt-phys-mapping.txt
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cachetlb.txt
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cgroup-v2.txt
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Changes
kbuild: verify that $DEPMOD is installed
2018-08-17 20:59:29 +02:00
circular-buffers.txt
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clk.txt
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CodeOfConflict
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CodingStyle
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conf.py
docs: Fix conf.py for Sphinx 2.0
2019-06-11 12:22:43 +02:00
cpu-hotplug.txt
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cpu-load.txt
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cputopology.txt
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crc32.txt
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dcdbas.txt
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debugging-modules.txt
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debugging-via-ohci1394.txt
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dell_rbu.txt
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devices.txt
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digsig.txt
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DMA-API-HOWTO.txt
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DMA-API.txt
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DMA-attributes.txt
dma-mapping: introduce the DMA_ATTR_NO_WARN attribute
2016-10-11 15:06:32 -07:00
dma-buf-sharing.txt
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DMA-ISA-LPC.txt
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docutils.conf
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dontdiff
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dynamic-debug-howto.txt
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edac.txt
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efi-stub.txt
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eisa.txt
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email-clients.txt
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flexible-arrays.txt
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futex-requeue-pi.txt
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gcc-plugins.txt
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highuid.txt
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HOWTO
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hw_random.txt
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hwspinlock.txt
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index.rst
Documentation: Move L1TF to separate directory
2019-05-14 19:19:41 +02:00
init.txt
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initrd.txt
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intel_txt.txt
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Intel-IOMMU.txt
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io_ordering.txt
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io-mapping.txt
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iostats.txt
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IPMI.txt
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IRQ-affinity.txt
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IRQ-domain.txt
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IRQ.txt
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irqflags-tracing.txt
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isa.txt
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isapnp.txt
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java.txt
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kernel-doc-nano-HOWTO.txt
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kernel-docs.txt
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kernel-documentation.rst
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kernel-parameters.txt
x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h
2019-09-06 10:19:41 +02:00
kernel-per-CPU-kthreads.txt
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kobject.txt
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kprobes.txt
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kref.txt
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kselftest.txt
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ldm.txt
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local_ops.txt
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lockup-watchdogs.txt
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logo.gif
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logo.txt
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lzo.txt
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magic-number.txt
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mailbox.txt
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Makefile
samples: move blackfin gptimers-example from Documentation
2016-10-10 07:12:02 -06:00
Makefile.sphinx
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ManagementStyle
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md-cluster.txt
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md.txt
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memory-barriers.txt
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memory-hotplug.txt
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men-chameleon-bus.txt
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module-signing.txt
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mono.txt
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nommu-mmap.txt
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ntb.txt
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numastat.txt
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oops-tracing.txt
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padata.txt
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parport-lowlevel.txt
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parport.txt
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percpu-rw-semaphore.txt
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phy.txt
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pi-futex.txt
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pinctrl.txt
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pnp.txt
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preempt-locking.txt
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printk-formats.txt
lib/vsprintf: Remove atomic-unsafe support for %pCr
2018-07-03 11:23:06 +02:00
pwm.txt
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ramoops.txt
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rbtree.txt
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remoteproc.txt
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rfkill.txt
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robust-futex-ABI.txt
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robust-futexes.txt
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rpmsg.txt
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rtc.txt
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SAK.txt
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SecurityBugs
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serial-console.txt
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sgi-ioc4.txt
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siphash.txt
siphash: implement HalfSipHash1-3 for hash tables
2019-08-25 10:51:42 +02:00
SM501.txt
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smsc_ece1099.txt
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spec_ctrl.txt
x86/speculation: Add prctl() control for indirect branch speculation
2019-05-14 19:19:39 +02:00
speculation.txt
Documentation: Document array_index_nospec
2018-02-13 12:35:59 +01:00
stable_api_nonsense.txt
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stable_kernel_rules.txt
Documentation: stable-kernel-rules: fix stable-tag format
2017-04-12 12:41:15 +02:00
static-keys.txt
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SubmitChecklist
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SubmittingDrivers
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SubmittingPatches
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svga.txt
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sync_file.txt
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sysfs-rules.txt
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sysrq.txt
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this_cpu_ops.txt
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unaligned-memory-access.txt
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unicode.txt
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unshare.txt
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vfio.txt
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VGA-softcursor.txt
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video-output.txt
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vme_api.txt
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volatile-considered-harmful.txt
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workqueue.txt
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xillybus.txt
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xz.txt
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zorro.txt
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