Pull STIBP fallout fixes from Thomas Gleixner:
"The performance destruction department finally got it's act together
and came up with a cure for the STIPB regression:
- Provide a command line option to control the spectre v2 user space
mitigations. Default is either seccomp or prctl (if seccomp is
disabled in Kconfig). prctl allows mitigation opt-in, seccomp
enables the migitation for sandboxed processes.
- Rework the code to handle the conditional STIBP/IBPB control and
remove the now unused ptrace_may_access_sched() optimization
attempt
- Disable STIBP automatically when SMT is disabled
- Optimize the switch_to() logic to avoid MSR writes and invocations
of __switch_to_xtra().
- Make the asynchronous speculation TIF updates synchronous to
prevent stale mitigation state.
As a general cleanup this also makes retpoline directly depend on
compiler support and removes the 'minimal retpoline' option which just
pretended to provide some form of security while providing none"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
x86/speculation: Provide IBPB always command line options
x86/speculation: Add seccomp Spectre v2 user space protection mode
x86/speculation: Enable prctl mode for spectre_v2_user
x86/speculation: Add prctl() control for indirect branch speculation
x86/speculation: Prepare arch_smt_update() for PRCTL mode
x86/speculation: Prevent stale SPEC_CTRL msr content
x86/speculation: Split out TIF update
ptrace: Remove unused ptrace_may_access_sched() and MODE_IBRS
x86/speculation: Prepare for conditional IBPB in switch_mm()
x86/speculation: Avoid __switch_to_xtra() calls
x86/process: Consolidate and simplify switch_to_xtra() code
x86/speculation: Prepare for per task indirect branch speculation control
x86/speculation: Add command line control for indirect branch speculation
x86/speculation: Unify conditional spectre v2 print functions
x86/speculataion: Mark command line parser data __initdata
x86/speculation: Mark string arrays const correctly
x86/speculation: Reorder the spec_v2 code
x86/l1tf: Show actual SMT state
x86/speculation: Rework SMT state change
sched/smt: Expose sched_smt_present static key
...
Mel Gorman reports a hackbench regression with psi that would prohibit
shipping the suse kernel with it default-enabled, but he'd still like
users to be able to opt in at little to no cost to others.
With the current combination of CONFIG_PSI and the psi_disabled bool set
from the commandline, this is a challenge. Do the following things to
make it easier:
1. Add a config option CONFIG_PSI_DEFAULT_DISABLED that allows distros
to enable CONFIG_PSI in their kernel but leave the feature disabled
unless a user requests it at boot-time.
To avoid double negatives, rename psi_disabled= to psi=.
2. Make psi_disabled a static branch to eliminate any branch costs
when the feature is disabled.
In terms of numbers before and after this patch, Mel says:
: The following is a comparision using CONFIG_PSI=n as a baseline against
: your patch and a vanilla kernel
:
: 4.20.0-rc4 4.20.0-rc4 4.20.0-rc4
: kconfigdisable-v1r1 vanilla psidisable-v1r1
: Amean 1 1.3100 ( 0.00%) 1.3923 ( -6.28%) 1.3427 ( -2.49%)
: Amean 3 3.8860 ( 0.00%) 4.1230 * -6.10%* 3.8860 ( -0.00%)
: Amean 5 6.8847 ( 0.00%) 8.0390 * -16.77%* 6.7727 ( 1.63%)
: Amean 7 9.9310 ( 0.00%) 10.8367 * -9.12%* 9.9910 ( -0.60%)
: Amean 12 16.6577 ( 0.00%) 18.2363 * -9.48%* 17.1083 ( -2.71%)
: Amean 18 26.5133 ( 0.00%) 27.8833 * -5.17%* 25.7663 ( 2.82%)
: Amean 24 34.3003 ( 0.00%) 34.6830 ( -1.12%) 32.0450 ( 6.58%)
: Amean 30 40.0063 ( 0.00%) 40.5800 ( -1.43%) 41.5087 ( -3.76%)
: Amean 32 40.1407 ( 0.00%) 41.2273 ( -2.71%) 39.9417 ( 0.50%)
:
: It's showing that the vanilla kernel takes a hit (as the bisection
: indicated it would) and that disabling PSI by default is reasonably
: close in terms of performance for this particular workload on this
: particular machine so;
Link: http://lkml.kernel.org/r/20181127165329.GA29728@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Provide the possibility to enable IBPB always in combination with 'prctl'
and 'seccomp'.
Add the extra command line options and rework the IBPB selection to
evaluate the command instead of the mode selected by the STIPB switch case.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185006.144047038@linutronix.de
If 'prctl' mode of user space protection from spectre v2 is selected
on the kernel command-line, STIBP and IBPB are applied on tasks which
restrict their indirect branch speculation via prctl.
SECCOMP enables the SSBD mitigation for sandboxed tasks already, so it
makes sense to prevent spectre v2 user space to user space attacks as
well.
The Intel mitigation guide documents how STIPB works:
Setting bit 1 (STIBP) of the IA32_SPEC_CTRL MSR on a logical processor
prevents the predicted targets of indirect branches on any logical
processor of that core from being controlled by software that executes
(or executed previously) on another logical processor of the same core.
Ergo setting STIBP protects the task itself from being attacked from a task
running on a different hyper-thread and protects the tasks running on
different hyper-threads from being attacked.
While the document suggests that the branch predictors are shielded between
the logical processors, the observed performance regressions suggest that
STIBP simply disables the branch predictor more or less completely. Of
course the document wording is vague, but the fact that there is also no
requirement for issuing IBPB when STIBP is used points clearly in that
direction. The kernel still issues IBPB even when STIBP is used until Intel
clarifies the whole mechanism.
IBPB is issued when the task switches out, so malicious sandbox code cannot
mistrain the branch predictor for the next user space task on the same
logical processor.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185006.051663132@linutronix.de
Now that all prerequisites are in place:
- Add the prctl command line option
- Default the 'auto' mode to 'prctl'
- When SMT state changes, update the static key which controls the
conditional STIBP evaluation on context switch.
- At init update the static key which controls the conditional IBPB
evaluation on context switch.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.958421388@linutronix.de
Add command line control for user space indirect branch speculation
mitigations. The new option is: spectre_v2_user=
The initial options are:
- on: Unconditionally enabled
- off: Unconditionally disabled
-auto: Kernel selects mitigation (default off for now)
When the spectre_v2= command line argument is either 'on' or 'off' this
implies that the application to application control follows that state even
if a contradicting spectre_v2_user= argument is supplied.
Originally-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.082720373@linutronix.de
Here are some small char/misc driver fixes for issues that have been
reported.
Nothing major, highlights include:
- gnss sync write fixes
- uio oops fix
- nvmem fixes
- other minor fixes and some documentation/maintainers updates
Full details are in the shortlog.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
"Here are some small char/misc driver fixes for issues that have been
reported.
Nothing major, highlights include:
- gnss sync write fixes
- uio oops fix
- nvmem fixes
- other minor fixes and some documentation/maintainers updates
Full details are in the shortlog.
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
Documentation/security-bugs: Postpone fix publication in exceptional cases
MAINTAINERS: Add Sasha as a stable branch maintainer
gnss: sirf: fix synchronous write timeout
gnss: serial: fix synchronous write timeout
uio: Fix an Oops on load
test_firmware: fix error return getting clobbered
nvmem: core: fix regression in of_nvmem_cell_get()
misc: atmel-ssc: Fix section annotation on atmel_ssc_get_driver_data
drivers/misc/sgi-gru: fix Spectre v1 vulnerability
Drivers: hv: kvp: Fix the recent regression caused by incorrect clean-up
slimbus: ngd: remove unnecessary check
Here are a number of small USB fixes for 4.20-rc4.
There's the usual xhci and dwc2/3 fixes as well as a few minor other
issues resolved for problems that have been reported. Full details are
in the shortlog.
All have been in linux-next for a while with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
"Here are a number of small USB fixes for 4.20-rc4.
There's the usual xhci and dwc2/3 fixes as well as a few minor other
issues resolved for problems that have been reported. Full details are
in the shortlog.
All have been in linux-next for a while with no reported issues"
* tag 'usb-4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: cdc-acm: add entry for Hiro (Conexant) modem
usb: xhci: Prevent bus suspend if a port connect change or polling state is detected
usb: core: Fix hub port connection events lost
usb: dwc3: gadget: fix ISOC TRB type on unaligned transfers
Revert "usb: gadget: ffs: Fix BUG when userland exits with submitted AIO transfers"
usb: dwc2: pci: Fix an error code in probe
usb: dwc3: Fix NULL pointer exception in dwc3_pci_remove()
xhci: Add quirk to workaround the errata seen on Cavium Thunder-X2 Soc
usb: xhci: fix timeout for transition from RExit to U0
usb: xhci: fix uninitialized completion when USB3 port got wrong status
xhci: Add check for invalid byte size error when UAS devices are connected.
xhci: handle port status events for removed USB3 hcd
xhci: Fix leaking USB3 shared_hcd at xhci removal
USB: misc: appledisplay: add 20" Apple Cinema Display
USB: quirks: Add no-lpm quirk for Raydium touchscreens
usb: quirks: Add delay-init quirk for Corsair K70 LUX RGB
USB: Wait for extra delay time after USB_PORT_FEAT_RESET for quirky hub
usb: dwc3: gadget: Properly check last unaligned/zero chain TRB
usb: dwc3: core: Clean up ULPI device
Kyle Huey reported that 'rr', a replay debugger, broke due to the following commit:
af3bdb991a ("perf/x86/intel: Add a separate Arch Perfmon v4 PMI handler")
Rework the 'disable_counter_freezing' __setup() parameter such that we
can explicitly enable/disable it and switch to default disabled.
To this purpose, rename the parameter to "perf_v4_pmi=" which is a much
better description and allows requiring a bool argument.
[ mingo: Improved the changelog some more. ]
Reported-by: Kyle Huey <me@kylehuey.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert O'Callahan <robert@ocallahan.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Link: http://lkml.kernel.org/r/20181120170842.GZ2131@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
At the request of the reporter, the Linux kernel security team offers to
postpone the publishing of a fix for up to 5 business days from the date
of a report.
While it is generally undesirable to keep a fix private after it has
been developed, this short window is intended to allow distributions to
package the fix into their kernel builds and permits early inclusion of
the security team in the case of a co-ordinated disclosure with other
parties. Unfortunately, discussions with major Linux distributions and
cloud providers has revealed that 5 business days is not sufficient to
achieve either of these two goals.
As an example, cloud providers need to roll out KVM security fixes to a
global fleet of hosts with sufficient early ramp-up and monitoring. An
end-to-end timeline of less than two weeks dramatically cuts into the
amount of early validation and increases the chance of guest-visible
regressions.
The consequence of this timeline mismatch is that security issues are
commonly fixed without the involvement of the Linux kernel security team
and are instead analysed and addressed by an ad-hoc group of developers
across companies contributing to Linux. In some cases, mainline (and
therefore the official stable kernels) can be left to languish for
extended periods of time. This undermines the Linux kernel security
process and puts upstream developers in a difficult position should they
find themselves involved with an undisclosed security problem that they
are unable to report due to restrictions from their employer.
To accommodate the needs of these users of the Linux kernel and
encourage them to engage with the Linux security team when security
issues are first uncovered, extend the maximum period for which fixes
may be delayed to 7 calendar days, or 14 calendar days in exceptional
cases, where the logistics of QA and large scale rollouts specifically
need to be accommodated. This brings parity with the linux-distros@
maximum embargo period of 14 calendar days.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Amit Shah <aams@amazon.com>
Cc: Laura Abbott <labbott@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Co-developed-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix a typo in the admin-guide documentation for cpufreq.
Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Devices connected under Terminus Technology Inc. Hub (1a40:0101) may
fail to work after the system resumes from suspend:
[ 206.063325] usb 3-2.4: reset full-speed USB device number 4 using xhci_hcd
[ 206.143691] usb 3-2.4: device descriptor read/64, error -32
[ 206.351671] usb 3-2.4: device descriptor read/64, error -32
Info for this hub:
T: Bus=03 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#= 2 Spd=480 MxCh= 4
D: Ver= 2.00 Cls=09(hub ) Sub=00 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=1a40 ProdID=0101 Rev=01.11
S: Product=USB 2.0 Hub
C: #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=100mA
I: If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub
Some expirements indicate that the USB devices connected to the hub are
innocent, it's the hub itself is to blame. The hub needs extra delay
time after it resets its port.
Hence wait for extra delay, if the device is connected to this quirky
hub.
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull x86 fixes from Ingo Molnar:
"A number of fixes and some late updates:
- make in_compat_syscall() behavior on x86-32 similar to other
platforms, this touches a number of generic files but is not
intended to impact non-x86 platforms.
- objtool fixes
- PAT preemption fix
- paravirt fixes/cleanups
- cpufeatures updates for new instructions
- earlyprintk quirk
- make microcode version in sysfs world-readable (it is already
world-readable in procfs)
- minor cleanups and fixes"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
compat: Cleanup in_compat_syscall() callers
x86/compat: Adjust in_compat_syscall() to generic code under !COMPAT
objtool: Support GCC 9 cold subfunction naming scheme
x86/numa_emulation: Fix uniform-split numa emulation
x86/paravirt: Remove unused _paravirt_ident_32
x86/mm/pat: Disable preemption around __flush_tlb_all()
x86/paravirt: Remove GPL from pv_ops export
x86/traps: Use format string with panic() call
x86: Clean up 'sizeof x' => 'sizeof(x)'
x86/cpufeatures: Enumerate MOVDIR64B instruction
x86/cpufeatures: Enumerate MOVDIRI instruction
x86/earlyprintk: Add a force option for pciserial device
objtool: Support per-function rodata sections
x86/microcode: Make revision and processor flags world-readable
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Merge tag 'for-linus-20181102' of git://git.kernel.dk/linux-block
Pull block layer fixes from Jens Axboe:
"The biggest part of this pull request is the revert of the blkcg
cleanup series. It had one fix earlier for a stacked device issue, but
another one was reported. Rather than play whack-a-mole with this,
revert the entire series and try again for the next kernel release.
Apart from that, only small fixes/changes.
Summary:
- Indentation fixup for mtip32xx (Colin Ian King)
- The blkcg cleanup series revert (Dennis Zhou)
- Two NVMe fixes. One fixing a regression in the nvme request
initialization in this merge window, causing nvme-fc to not work.
The other is a suspend/resume p2p resource issue (James, Keith)
- Fix sg discard merge, allowing us to merge in cases where we didn't
before (Jianchao Wang)
- Call rq_qos_exit() after the queue is frozen, preventing a hang
(Ming)
- Fix brd queue setup, fixing an oops if we fail setting up all
devices (Ming)"
* tag 'for-linus-20181102' of git://git.kernel.dk/linux-block:
nvme-pci: fix conflicting p2p resource adds
nvme-fc: fix request private initialization
blkcg: revert blkcg cleanups series
block: brd: associate with queue until adding disk
block: call rq_qos_exit() after queue is frozen
mtip32xx: clean an indentation issue, remove extraneous tabs
block: fix the DISCARD request merge
Let's document the magic a bit, especially why device_hotplug_lock is
required when adding/removing memory and how it all play together with
requests to online/offline memory from user space.
Link: http://lkml.kernel.org/r/20180925091457.28651-7-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com>
Reviewed-by: Rashmica Gupta <rashmica.g@gmail.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: John Allen <jallen@linux.vnet.ibm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mathieu Malaterre <malat@debian.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge updates from Andrew Morton:
- a few misc things
- ocfs2 updates
- most of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (132 commits)
hugetlbfs: dirty pages as they are added to pagecache
mm: export add_swap_extent()
mm: split SWP_FILE into SWP_ACTIVATED and SWP_FS
tools/testing/selftests/vm/map_fixed_noreplace.c: add test for MAP_FIXED_NOREPLACE
mm: thp: relocate flush_cache_range() in migrate_misplaced_transhuge_page()
mm: thp: fix mmu_notifier in migrate_misplaced_transhuge_page()
mm: thp: fix MADV_DONTNEED vs migrate_misplaced_transhuge_page race condition
mm/kasan/quarantine.c: make quarantine_lock a raw_spinlock_t
mm/gup: cache dev_pagemap while pinning pages
Revert "x86/e820: put !E820_TYPE_RAM regions into memblock.reserved"
mm: return zero_resv_unavail optimization
mm: zero remaining unavailable struct pages
tools/testing/selftests/vm/gup_benchmark.c: add MAP_HUGETLB option
tools/testing/selftests/vm/gup_benchmark.c: add MAP_SHARED option
tools/testing/selftests/vm/gup_benchmark.c: allow user specified file
tools/testing/selftests/vm/gup_benchmark.c: fix 'write' flag usage
mm/gup_benchmark.c: add additional pinning methods
mm/gup_benchmark.c: time put_page()
mm: don't raise MEMCG_OOM event due to failed high-order allocation
mm/page-writeback.c: fix range_cyclic writeback vs writepages deadlock
...
It was reported that on some of our machines containers were restarted
with OOM symptoms without an obvious reason. Despite there were almost no
memory pressure and plenty of page cache, MEMCG_OOM event was raised
occasionally, causing the container management software to think, that OOM
has happened. However, no tasks have been killed.
The following investigation showed that the problem is caused by a failing
attempt to charge a high-order page. In such case, the OOM killer is
never invoked. As shown below, it can happen under conditions, which are
very far from a real OOM: e.g. there is plenty of clean page cache and no
memory pressure.
There is no sense in raising an OOM event in this case, as it might
confuse a user and lead to wrong and excessive actions (e.g. restart the
workload, as in my case).
Let's look at the charging path in try_charge(). If the memory usage is
about memory.max, which is absolutely natural for most memory cgroups, we
try to reclaim some pages. Even if we were able to reclaim enough memory
for the allocation, the following check can fail due to a race with
another concurrent allocation:
if (mem_cgroup_margin(mem_over_limit) >= nr_pages)
goto retry;
For regular pages the following condition will save us from triggering
the OOM:
if (nr_reclaimed && nr_pages <= (1 << PAGE_ALLOC_COSTLY_ORDER))
goto retry;
But for high-order allocation this condition will intentionally fail. The
reason behind is that we'll likely fall to regular pages anyway, so it's
ok and even preferred to return ENOMEM.
In this case the idea of raising MEMCG_OOM looks dubious.
Fix this by moving MEMCG_OOM raising to mem_cgroup_oom() after allocation
order check, so that the event won't be raised for high order allocations.
This change doesn't affect regular pages allocation and charging.
Link: http://lkml.kernel.org/r/20181004214050.7417-1-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "Address issues slowing persistent memory initialization", v5.
The main thing this patch set achieves is that it allows us to initialize
each node worth of persistent memory independently. As a result we reduce
page init time by about 2 minutes because instead of taking 30 to 40
seconds per node and going through each node one at a time, we process all
4 nodes in parallel in the case of a 12TB persistent memory setup spread
evenly over 4 nodes.
This patch (of 3):
On systems with a large amount of memory it can take a significant amount
of time to initialize all of the page structs with the PAGE_POISON_PATTERN
value. I have seen it take over 2 minutes to initialize a system with
over 12TB of RAM.
In order to work around the issue I had to disable CONFIG_DEBUG_VM and
then the boot time returned to something much more reasonable as the
arch_add_memory call completed in milliseconds versus seconds. However in
doing that I had to disable all of the other VM debugging on the system.
In order to work around a kernel that might have CONFIG_DEBUG_VM enabled
on a system that has a large amount of memory I have added a new kernel
parameter named "vm_debug" that can be set to "-" in order to disable it.
Link: http://lkml.kernel.org/r/20180925201921.3576.84239.stgit@localhost.localdomain
Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On a system that executes multiple cgrouped jobs and independent
workloads, we don't just care about the health of the overall system, but
also that of individual jobs, so that we can ensure individual job health,
fairness between jobs, or prioritize some jobs over others.
This patch implements pressure stall tracking for cgroups. In kernels
with CONFIG_PSI=y, cgroup2 groups will have cpu.pressure, memory.pressure,
and io.pressure files that track aggregate pressure stall times for only
the tasks inside the cgroup.
Link: http://lkml.kernel.org/r/20180828172258.3185-10-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Drake <drake@endlessm.com>
Tested-by: Suren Baghdasaryan <surenb@google.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Weiner <jweiner@fb.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Enderborg <peter.enderborg@sony.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These updates bring:
- Debugfs support for the Intel VT-d driver. When enabled, it
now also exposes some of its internal data structures to
user-space for debugging purposes.
- ARM-SMMU driver now uses the generic deferred flushing
and fast-path iova allocation code. This is expected to be a
major performance improvement, as this allocation path scales
a lot better.
- Support for r8a7744 in the Renesas iommu driver
- Couple of minor fixes and improvements all over the place
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Merge tag 'iommu-updates-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel:
- Debugfs support for the Intel VT-d driver.
When enabled, it now also exposes some of its internal data
structures to user-space for debugging purposes.
- ARM-SMMU driver now uses the generic deferred flushing and fast-path
iova allocation code.
This is expected to be a major performance improvement, as this
allocation path scales a lot better.
- Support for r8a7744 in the Renesas iommu driver
- Couple of minor fixes and improvements all over the place
* tag 'iommu-updates-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (39 commits)
iommu/arm-smmu-v3: Remove unnecessary wrapper function
iommu/arm-smmu-v3: Add SPDX header
iommu/amd: Add default branch in amd_iommu_capable()
dt-bindings: iommu: ipmmu-vmsa: Add r8a7744 support
iommu/amd: Move iommu_init_pci() to .init section
iommu/arm-smmu: Support non-strict mode
iommu/io-pgtable-arm-v7s: Add support for non-strict mode
iommu/arm-smmu-v3: Add support for non-strict mode
iommu/io-pgtable-arm: Add support for non-strict mode
iommu: Add "iommu.strict" command line option
iommu/dma: Add support for non-strict mode
iommu/arm-smmu: Ensure that page-table updates are visible before TLBI
iommu/arm-smmu-v3: Implement flush_iotlb_all hook
iommu/arm-smmu-v3: Avoid back-to-back CMD_SYNC operations
iommu/arm-smmu-v3: Fix unexpected CMD_SYNC timeout
iommu/io-pgtable-arm: Fix race handling in split_blk_unmap()
iommu/arm-smmu-v3: Fix a couple of minor comment typos
iommu: Fix a typo
iommu: Remove .domain_{get,set}_windows
iommu: Tidy up window attributes
...
Here is the big set of char/misc patches for 4.20-rc1.
Loads of things here, we have new code in all of these driver
subsystems:
fpga
stm
extcon
nvmem
eeprom
hyper-v
gsmi
coresight
thunderbolt
vmw_balloon
goldfish
soundwire
along with lots of fixes and minor changes to other small drivers.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here is the big set of char/misc patches for 4.20-rc1.
Loads of things here, we have new code in all of these driver
subsystems:
- fpga
- stm
- extcon
- nvmem
- eeprom
- hyper-v
- gsmi
- coresight
- thunderbolt
- vmw_balloon
- goldfish
- soundwire
along with lots of fixes and minor changes to other small drivers.
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (245 commits)
Documentation/security-bugs: Clarify treatment of embargoed information
lib: Fix ia64 bootloader linkage
MAINTAINERS: Clarify UIO vs UIOVEC maintainer
docs/uio: fix a grammar nitpick
docs: fpga: document programming fpgas using regions
fpga: add devm_fpga_region_create
fpga: bridge: add devm_fpga_bridge_create
fpga: mgr: add devm_fpga_mgr_create
hv_balloon: Replace spin_is_locked() with lockdep
sgi-xp: Replace spin_is_locked() with lockdep
eeprom: New ee1004 driver for DDR4 memory
eeprom: at25: remove unneeded 'at25_remove'
w1: IAD Register is yet readable trough iad sys file. Fix snprintf (%u for unsigned, count for max size).
misc: mic: scif: remove set but not used variables 'src_dma_addr, dst_dma_addr'
misc: mic: fix a DMA pool free failure
platform: goldfish: pipe: Add a blank line to separate varibles and code
platform: goldfish: pipe: Remove redundant casting
platform: goldfish: pipe: Call misc_deregister if init fails
platform: goldfish: pipe: Move the file-scope goldfish_pipe_dev variable into the driver state
platform: goldfish: pipe: Move the file-scope goldfish_pipe_miscdev variable into the driver state
...
Here is the big USB/PHY driver patches for 4.20-rc1
Lots of USB changes in here, primarily in these areas:
- typec updates and new drivers
- new PHY drivers
- dwc2 driver updates and additions (this old core keeps getting added
to new devices.)
- usbtmc major update based on the industry group coming together and
working to add new features and performance to the driver.
- USB gadget additions for new features
- USB gadget configfs updates
- chipidea driver updates
- other USB gadget updates
- USB serial driver updates
- renesas driver updates
- xhci driver updates
- other tiny USB driver updates
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB/PHY updates from Greg KH:
"Here is the big USB/PHY driver patches for 4.20-rc1
Lots of USB changes in here, primarily in these areas:
- typec updates and new drivers
- new PHY drivers
- dwc2 driver updates and additions (this old core keeps getting
added to new devices.)
- usbtmc major update based on the industry group coming together and
working to add new features and performance to the driver.
- USB gadget additions for new features
- USB gadget configfs updates
- chipidea driver updates
- other USB gadget updates
- USB serial driver updates
- renesas driver updates
- xhci driver updates
- other tiny USB driver updates
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (229 commits)
usb: phy: ab8500: silence some uninitialized variable warnings
usb: xhci: tegra: Add genpd support
usb: xhci: tegra: Power-off power-domains on removal
usbip:vudc: BUG kmalloc-2048 (Not tainted): Poison overwritten
usbip: tools: fix atoi() on non-null terminated string
USB: misc: appledisplay: fix backlight update_status return code
phy: phy-pxa-usb: add a new driver
usb: host: add DT bindings for faraday fotg2
usb: host: ohci-at91: fix request of irq for optional gpio
usb/early: remove set but not used variable 'remain_length'
usb: typec: Fix copy/paste on typec_set_vconn_role() kerneldoc
usb: typec: tcpm: Report back negotiated PPS voltage and current
USB: core: remove set but not used variable 'udev'
usb: core: fix memory leak on port_dev_path allocation
USB: net2280: Remove ->disconnect() callback from net2280_pullup()
usb: dwc2: disable power_down on rockchip devices
usb: gadget: udc: renesas_usb3: add support for r8a77990
dt-bindings: usb: renesas_usb3: add bindings for r8a77990
usb: gadget: udc: renesas_usb3: Add r8a774a1 support
USB: serial: cypress_m8: remove set but not used variable 'iflag'
...
readability improvements for the formatted output, some LICENSES updates
including the addition of the ISC license, the removal of the unloved and
unmaintained 00-INDEX files, the deprecated APIs document from Kees, more
MM docs from Mike Rapoport, and the usual pile of typo fixes and
corrections.
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Merge tag 'docs-4.20' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"This is a fairly typical cycle for documentation. There's some welcome
readability improvements for the formatted output, some LICENSES
updates including the addition of the ISC license, the removal of the
unloved and unmaintained 00-INDEX files, the deprecated APIs document
from Kees, more MM docs from Mike Rapoport, and the usual pile of typo
fixes and corrections"
* tag 'docs-4.20' of git://git.lwn.net/linux: (41 commits)
docs: Fix typos in histogram.rst
docs: Introduce deprecated APIs list
kernel-doc: fix declaration type determination
doc: fix a typo in adding-syscalls.rst
docs/admin-guide: memory-hotplug: remove table of contents
doc: printk-formats: Remove bogus kobject references for device nodes
Documentation: preempt-locking: Use better example
dm flakey: Document "error_writes" feature
docs/completion.txt: Fix a couple of punctuation nits
LICENSES: Add ISC license text
LICENSES: Add note to CDDL-1.0 license that it should not be used
docs/core-api: memory-hotplug: add some details about locking internals
docs/core-api: rename memory-hotplug-notifier to memory-hotplug
docs: improve readability for people with poorer eyesight
yama: clarify ptrace_scope=2 in Yama documentation
docs/vm: split memory hotplug notifier description to Documentation/core-api
docs: move memory hotplug description into admin-guide/mm
doc: Fix acronym "FEKEK" in ecryptfs
docs: fix some broken documentation references
iommu: Fix passthrough option documentation
...
allocation for bigalloc file systems; fix up some syzbot-detected
races in EXT4_IOC_MOVE_EXT, EXT4_IOC_SWAP_BOOT, and ext4_remount; and
a few other miscellaneous bugs and optimizations.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
- further restructure ext4 documentation
- fix up ext4's delayed allocation for bigalloc file systems
- fix up some syzbot-detected races in EXT4_IOC_MOVE_EXT,
EXT4_IOC_SWAP_BOOT, and ext4_remount
- ... and a few other miscellaneous bugs and optimizations.
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (21 commits)
ext4: fix use-after-free race in ext4_remount()'s error path
ext4: cache NULL when both default_acl and acl are NULL
docs: promote the ext4 data structures book to top level
docs: move ext4 administrative docs to admin-guide/
jbd2: fix use after free in jbd2_log_do_checkpoint()
ext4: propagate error from dquot_initialize() in EXT4_IOC_FSSETXATTR
ext4: fix setattr project check in fssetxattr ioctl
docs: make ext4 readme tables readable
docs: fix ext4 documentation table formatting problems
docs: generate a separate ext4 pdf file from the documentation
ext4: convert fault handler to use vm_fault_t type
ext4: initialize retries variable in ext4_da_write_inline_data_begin()
ext4: fix EXT4_IOC_SWAP_BOOT
ext4: fix build error when DX_DEBUG is defined
ext4: fix argument checking in EXT4_IOC_MOVE_EXT
ext4: fix reserved cluster accounting at page invalidation time
ext4: adjust reserved cluster count when removing extents
ext4: reduce reserved cluster count by number of allocated clusters
ext4: fix reserved cluster accounting at delayed write time
ext4: add new pending reservation mechanism
...
Pull security subsystem updates from James Morris:
"In this patchset, there are a couple of minor updates, as well as some
reworking of the LSM initialization code from Kees Cook (these prepare
the way for ordered stackable LSMs, but are a valuable cleanup on
their own)"
* 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
LSM: Don't ignore initialization failures
LSM: Provide init debugging infrastructure
LSM: Record LSM name in struct lsm_info
LSM: Convert security_initcall() into DEFINE_LSM()
vmlinux.lds.h: Move LSM_TABLE into INIT_DATA
LSM: Convert from initcall to struct lsm_info
LSM: Remove initcall tracing
LSM: Rename .security_initcall section to .lsm_info
vmlinux.lds.h: Avoid copy/paste of security_init section
LSM: Correctly announce start of LSM initialization
security: fix LSM description location
keys: Fix the use of the C++ keyword "private" in uapi/linux/keyctl.h
seccomp: remove unnecessary unlikely()
security: tomoyo: Fix obsolete function
security/capabilities: remove check for -EINVAL
Pull x86 paravirt updates from Ingo Molnar:
"Two main changes:
- Remove no longer used parts of the paravirt infrastructure and put
large quantities of paravirt ops under a new config option
PARAVIRT_XXL=y, which is selected by XEN_PV only. (Joergen Gross)
- Enable PV spinlocks on Hyperv (Yi Sun)"
* 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/hyperv: Enable PV qspinlock for Hyper-V
x86/hyperv: Add GUEST_IDLE_MSR support
x86/paravirt: Clean up native_patch()
x86/paravirt: Prevent redefinition of SAVE_FLAGS macro
x86/xen: Make xen_reservation_lock static
x86/paravirt: Remove unneeded mmu related paravirt ops bits
x86/paravirt: Move the Xen-only pv_mmu_ops under the PARAVIRT_XXL umbrella
x86/paravirt: Move the pv_irq_ops under the PARAVIRT_XXL umbrella
x86/paravirt: Move the Xen-only pv_cpu_ops under the PARAVIRT_XXL umbrella
x86/paravirt: Move items in pv_info under PARAVIRT_XXL umbrella
x86/paravirt: Introduce new config option PARAVIRT_XXL
x86/paravirt: Remove unused paravirt bits
x86/paravirt: Use a single ops structure
x86/paravirt: Remove clobbers from struct paravirt_patch_site
x86/paravirt: Remove clobbers parameter from paravirt patch functions
x86/paravirt: Make paravirt_patch_call() and paravirt_patch_jmp() static
x86/xen: Add SPDX identifier in arch/x86/xen files
x86/xen: Link platform-pci-unplug.o only if CONFIG_XEN_PVHVM
x86/xen: Move pv specific parts of arch/x86/xen/mmu.c to mmu_pv.c
x86/xen: Move pv irq related functions under CONFIG_XEN_PV umbrella
The Linux kernel security team has been accused of rejecting the idea of
security embargoes. This is incorrect, and could dissuade people from
reporting security issues to us under the false assumption that the
issue would leak prematurely.
Clarify the handling of embargoed information in our process
documentation.
Co-developed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull RCU updates from Ingo Molnar:
"The biggest change in this cycle is the conclusion of the big
'simplify RCU to two primary flavors' consolidation work - i.e.
there's a single RCU flavor for any kernel variant (PREEMPT and
!PREEMPT):
- Consolidate the RCU-bh, RCU-preempt, and RCU-sched flavors into a
single flavor similar to RCU-sched in !PREEMPT kernels and into a
single flavor similar to RCU-preempt (but also waiting on
preempt-disabled sequences of code) in PREEMPT kernels.
This branch also includes a refactoring of
rcu_{nmi,irq}_{enter,exit}() from Byungchul Park.
- Now that there is only one RCU flavor in any given running kernel,
the many "rsp" pointers are no longer required, and this cleanup
series removes them.
- This branch carries out additional cleanups made possible by the
RCU flavor consolidation, including inlining now-trivial
functions, updating comments and definitions, and removing
now-unneeded rcutorture scenarios.
- Now that there is only one flavor of RCU in any running kernel,
there is also only on rcu_data structure per CPU. This means that
the rcu_dynticks structure can be merged into the rcu_data
structure, a task taken on by this branch. This branch also
contains a -rt-related fix from Mike Galbraith.
There were also other updates:
- Documentation updates, including some good-eye catches from Joel
Fernandes.
- SRCU updates, most notably changes enabling call_srcu() to be
invoked very early in the boot sequence.
- Torture-test updates, including some preliminary work towards
making rcutorture better able to find problems that result in
insufficient grace-period forward progress.
- Initial changes to RCU to better promote forward progress of grace
periods, including fixing a bug found by Marius Hillenbrand and
David Woodhouse, with the fix suggested by Peter Zijlstra"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (140 commits)
srcu: Make early-boot call_srcu() reuse workqueue lists
rcutorture: Test early boot call_srcu()
srcu: Make call_srcu() available during very early boot
rcu: Convert rcu_state.ofl_lock to raw_spinlock_t
rcu: Remove obsolete ->dynticks_fqs and ->cond_resched_completed
rcu: Switch ->dynticks to rcu_data structure, remove rcu_dynticks
rcu: Switch dyntick nesting counters to rcu_data structure
rcu: Switch urgent quiescent-state requests to rcu_data structure
rcu: Switch lazy counts to rcu_data structure
rcu: Switch last accelerate/advance to rcu_data structure
rcu: Switch ->tick_nohz_enabled_snap to rcu_data structure
rcu: Merge rcu_dynticks structure into rcu_data structure
rcu: Remove unused rcu_dynticks_snap() from Tiny RCU
rcu: Convert "1UL << x" to "BIT(x)"
rcu: Avoid resched_cpu() when rescheduling the current CPU
rcu: More aggressively enlist scheduler aid for nohz_full CPUs
rcu: Compute jiffies_till_sched_qs from other kernel parameters
rcu: Provide functions for determining if call_rcu() has been invoked
rcu: Eliminate ->rcu_qs_ctr from the rcu_dynticks structure
rcu: Motivate Tiny RCU forward progress
...
- Backport hibernation bug fixes from x86-64 to x86-32 and
consolidate hibernation handling on x86 to allow 32-bit
systems to work in all of the cases in which 64-bit ones
work (Zhimin Gu, Chen Yu).
- Fix hibernation documentation (Vladimir D. Seleznev).
- Update the menu cpuidle governor to fix a couple of issues
with it, make it more efficient in some cases and clean it
up (Rafael Wysocki).
- Rework the cpuidle polling state implementation to make it
more efficient (Rafael Wysocki).
- Clean up the cpuidle core somewhat (Fieah Lim).
- Fix the cpufreq conservative governor to take policy limits
into account properly in some cases (Rafael Wysocki).
- Add support for retrieving guaranteed performance information
to the ACPI CPPC library and make the intel_pstate driver use
it to expose the CPU base frequency via sysfs on systems with
the hardware-managed P-states (HWP) feature enabled (Srinivas
Pandruvada).
- Fix clang warning in the CPPC cpufreq driver (Nathan Chancellor).
- Get rid of device_node.name printing from cpufreq (Rob Herring).
- Remove unnecessary unlikely() from the cpufreq core (Igor Stoppa).
- Add support for the r8a7744 SoC to the cpufreq-dt driver (Biju Das).
- Update the dt-platdev cpufreq driver to allow RK3399 to have
separate tunables per cluster (Dmitry Torokhov).
- Fix the dma_alloc_coherent() usage in the tegra186 cpufreq driver
(Christoph Hellwig).
- Make the imx6q cpufreq driver read OCOTP through nvmem for
imx6ul/imx6ull (Anson Huang).
- Fix several bugs in the operating performance points (OPP)
framework and make it more stable (Viresh Kumar, Dave Gerlach).
- Update the devfreq subsystem to take changes in the APIs used
by into account, fix some issues with it and make it stop
print device_node.name directly (Bjorn Andersson, Enric Balletbo
i Serra, Matthias Kaehlcke, Rob Herring, Vincent Donnefort, zhong
jiang).
- Prepare the generic power domains (genpd) framework for dealing
with domains containing CPUs (Ulf Hansson).
- Prevent sysfs attributes representing low-power S0 residency
counters from being exposed if low-power S0 support is not
indicated in ACPI FADT (Rajneesh Bhardwaj).
- Get rid of custom CPU features macros for Intel CPUs from the
intel_idle and RAPL drivers (Andy Shevchenko).
- Update the tasks freezer to list tasks that refused to freeze
and caused a system transition to a sleep state to be aborted
(Todd Brandt).
- Update the pm-graph set of tools to v5.2 (Todd Brandt).
- Fix some issues in the cpupower utility (Anders Roxell, Prarit
Bhargava).
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Merge tag 'pm-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These make hibernation on 32-bit x86 systems work in all of the cases
in which it works on 64-bit x86 ones, update the menu cpuidle governor
and the "polling" state to make them more efficient, add more hardware
support to cpufreq drivers and fix issues with some of them, fix a bug
in the conservative cpufreq governor, fix the operating performance
points (OPP) framework and make it more stable, update the devfreq
subsystem to take changes in the APIs used by into account and clean
up some things all over.
Specifics:
- Backport hibernation bug fixes from x86-64 to x86-32 and
consolidate hibernation handling on x86 to allow 32-bit systems to
work in all of the cases in which 64-bit ones work (Zhimin Gu, Chen
Yu).
- Fix hibernation documentation (Vladimir D. Seleznev).
- Update the menu cpuidle governor to fix a couple of issues with it,
make it more efficient in some cases and clean it up (Rafael
Wysocki).
- Rework the cpuidle polling state implementation to make it more
efficient (Rafael Wysocki).
- Clean up the cpuidle core somewhat (Fieah Lim).
- Fix the cpufreq conservative governor to take policy limits into
account properly in some cases (Rafael Wysocki).
- Add support for retrieving guaranteed performance information to
the ACPI CPPC library and make the intel_pstate driver use it to
expose the CPU base frequency via sysfs on systems with the
hardware-managed P-states (HWP) feature enabled (Srinivas
Pandruvada).
- Fix clang warning in the CPPC cpufreq driver (Nathan Chancellor).
- Get rid of device_node.name printing from cpufreq (Rob Herring).
- Remove unnecessary unlikely() from the cpufreq core (Igor Stoppa).
- Add support for the r8a7744 SoC to the cpufreq-dt driver (Biju
Das).
- Update the dt-platdev cpufreq driver to allow RK3399 to have
separate tunables per cluster (Dmitry Torokhov).
- Fix the dma_alloc_coherent() usage in the tegra186 cpufreq driver
(Christoph Hellwig).
- Make the imx6q cpufreq driver read OCOTP through nvmem for
imx6ul/imx6ull (Anson Huang).
- Fix several bugs in the operating performance points (OPP)
framework and make it more stable (Viresh Kumar, Dave Gerlach).
- Update the devfreq subsystem to take changes in the APIs used by
into account, fix some issues with it and make it stop print
device_node.name directly (Bjorn Andersson, Enric Balletbo i Serra,
Matthias Kaehlcke, Rob Herring, Vincent Donnefort, zhong jiang).
- Prepare the generic power domains (genpd) framework for dealing
with domains containing CPUs (Ulf Hansson).
- Prevent sysfs attributes representing low-power S0 residency
counters from being exposed if low-power S0 support is not
indicated in ACPI FADT (Rajneesh Bhardwaj).
- Get rid of custom CPU features macros for Intel CPUs from the
intel_idle and RAPL drivers (Andy Shevchenko).
- Update the tasks freezer to list tasks that refused to freeze and
caused a system transition to a sleep state to be aborted (Todd
Brandt).
- Update the pm-graph set of tools to v5.2 (Todd Brandt).
- Fix some issues in the cpupower utility (Anders Roxell, Prarit
Bhargava)"
* tag 'pm-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (73 commits)
PM / Domains: Document flags for genpd
PM / Domains: Deal with multiple states but no governor in genpd
PM / Domains: Don't treat zero found compatible idle states as an error
cpuidle: menu: Avoid computations when result will be discarded
cpuidle: menu: Drop redundant comparison
cpufreq: tegra186: don't pass GFP_DMA32 to dma_alloc_coherent()
cpufreq: conservative: Take limits changes into account properly
Documentation: intel_pstate: Add base_frequency information
cpufreq: intel_pstate: Add base_frequency attribute
ACPI / CPPC: Add support for guaranteed performance
cpuidle: menu: Simplify checks related to the polling state
PM / tools: sleepgraph and bootgraph: upgrade to v5.2
PM / tools: sleepgraph: first batch of v5.2 changes
cpupower: Fix coredump on VMWare
cpupower: Fix AMD Family 0x17 msr_pstate size
cpufreq: imx6q: read OCOTP through nvmem for imx6ul/imx6ull
cpufreq: dt-platdev: allow RK3399 to have separate tunables per cluster
cpuidle: poll_state: Revise loop termination condition
cpuidle: menu: Move the latency_req == 0 special case check
cpuidle: menu: Avoid computations for very close timers
...
Updated documentation to explain base_frequency attribute.
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Remove "manual" table of contents and leave only the ReST tag so that
Sphinx will take care of TOC generation.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Booting with "lsm.debug" will report future details on how LSM ordering
decisions are being made.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: James Morris <james.morris@microsoft.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
Implement the required wait and kick callbacks to support PV spinlocks in
Hyper-V guests.
[ tglx: Document the requirement for disabling interrupts in the wait()
callback. Remove goto and unnecessary includes. Add prototype
for hv_vcpu_is_preempted(). Adapted to pending paravirt changes. ]
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Michael Kelley (EOSG) <Michael.H.Kelley@microsoft.com>
Cc: chao.p.peng@intel.com
Cc: chao.gao@intel.com
Cc: isaku.yamahata@intel.com
Cc: tianyu.lan@microsoft.com
Link: https://lkml.kernel.org/r/1538987374-51217-3-git-send-email-yi.y.sun@linux.intel.com
Current phrasing is ambiguous since it's unclear if attaching to a
children through PTRACE_TRACEME requires CAP_SYS_PTRACE. Rephrase the
sentence to make that clear.
Signed-off-by: Yves-Alexis Perez <corsac@corsac.net>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The memory hotplug notifier description is about kernel internals rather
than admin/user visible API. Place it appropriately.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The memory hotplug description in Documentation/memory-hotplug.txt is
already formatted as ReST and can be easily added to admin-guide/mm
section.
While on it, slightly update formatting to make it consistent with the
doc-guide.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Move the ext4 mount option and other administrative stuff to the Linux
administrator's guide.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Add call to early_memtest() so that kernel compiled with
CONFIG_MEMTEST really perform memtest at startup when requested
via 'memtest' boot parameter.
Tested-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The new scheme is required just to support legacy low and full-speed
devices. For high speed devices, it will slower the enumeration speed.
So in this patch we try the "old" enumeration scheme first for high speed
devices, and this is what Windows does since Windows 8.
Signed-off-by: Zeng Tao <prime.zeng@hisilicon.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Reviewed-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "pciserial" earlyprintk variant helps much on many modern x86
platforms, but unfortunately there are still some platforms with PCI
UART devices which have the wrong PCI class code. In that case, the
current class code check does not allow for them to be used for logging.
Add a sub-option "force" which overrides the class code check and thus
the use of such device can be enforced.
[ bp: massage formulations. ]
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Stuart R . Anderson" <stuart.r.anderson@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H Peter Anvin <hpa@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thymo van Beers <thymovanbeers@gmail.com>
Cc: alan@linux.intel.com
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/20181002164921.25833-1-feng.tang@intel.com
Pull v4.20 RCU changes from Paul E. McKenney:
- Documentation updates, including some good-eye catches from
Joel Fernandes.
- SRCU updates, most notably changes enabling call_srcu() to be
invoked very early in the boot sequence.
- Torture-test updates, including some preliminary work towards
making rcutorture better able to find problems that result in
insufficient grace-period forward progress.
- Consolidate the RCU-bh, RCU-preempt, and RCU-sched flavors into
a single flavor similar to RCU-sched in !PREEMPT kernels and
into a single flavor similar to RCU-preempt (but also waiting
on preempt-disabled sequences of code) in PREEMPT kernels. This
branch also includes a refactoring of rcu_{nmi,irq}_{enter,exit}()
from Byungchul Park.
- Now that there is only one RCU flavor in any given running kernel,
the many "rsp" pointers are no longer required, and this cleanup
series removes them.
- This branch carries out additional cleanups made possible by
the RCU flavor consolidation, including inlining how-trivial
functions, updating comments and definitions, and removing
now-unneeded rcutorture scenarios.
- Initial changes to RCU to better promote forward progress of
grace periods, including fixing a bug found by Marius Hillenbrand
and David Woodhouse, with the fix suggested by Peter Zijlstra.
- Now that there is only one flavor of RCU in any running kernel,
there is also only on rcu_data structure per CPU. This means
that the rcu_dynticks structure can be merged into the rcu_data
structure, a task taken on by this branch. This branch also
contains a -rt-related fix from Mike Galbraith.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Implements counter freezing for Arch Perfmon v4 (Skylake and
newer). This allows to speed up the PMI handler by avoiding
unnecessary MSR writes and make it more accurate.
The Arch Perfmon v4 PMI handler is substantially different than
the older PMI handler.
Differences to the old handler:
- It relies on counter freezing, which eliminates several MSR
writes from the PMI handler and lowers the overhead significantly.
It makes the PMI handler more accurate, as all counters get
frozen atomically as soon as any counter overflows. So there is
much less counting of the PMI handler itself.
With the freezing we don't need to disable or enable counters or
PEBS. Only BTS which does not support auto-freezing still needs to
be explicitly managed.
- The PMU acking is done at the end, not the beginning.
This makes it possible to avoid manual enabling/disabling
of the PMU, instead we just rely on the freezing/acking.
- The APIC is acked before reenabling the PMU, which avoids
problems with LBRs occasionally not getting unfreezed on Skylake.
- Looping is only needed to workaround a corner case which several PMIs
are very close to each other. For common cases, the counters are freezed
during PMI handler. It doesn't need to do re-check.
This patch:
- Adds code to enable v4 counter freezing
- Fork <=v3 and >=v4 PMI handlers into separate functions.
- Add kernel parameter to disable counter freezing. It took some time to
debug counter freezing, so in case there are new problems we added an
option to turn it off. Would not expect this to be used until there
are new bugs.
- Only for big core. The patch for small core will be posted later
separately.
Performance:
When profiling a kernel build on Kabylake with different perf options,
measuring the length of all NMI handlers using the nmi handler
trace point:
V3 is without counter freezing.
V4 is with counter freezing.
The value is the average cost of the PMI handler.
(lower is better)
perf options ` V3(ns) V4(ns) delta
-c 100000 1088 894 -18%
-g -c 100000 1862 1646 -12%
--call-graph lbr -c 100000 3649 3367 -8%
--c.g. dwarf -c 100000 2248 1982 -12%
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Link: http://lkml.kernel.org/r/1533712328-2834-2-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'v4.19-rc6' into for-4.20/block
Merge -rc6 in, for two reasons:
1) Resolve a trivial conflict in the blk-mq-tag.c documentation
2) A few important regression fixes went into upstream directly, so
they aren't in the 4.20 branch.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
* tag 'v4.19-rc6': (780 commits)
Linux 4.19-rc6
MAINTAINERS: fix reference to moved drivers/{misc => auxdisplay}/panel.c
cpufreq: qcom-kryo: Fix section annotations
perf/core: Add sanity check to deal with pinned event failure
xen/blkfront: correct purging of persistent grants
Revert "xen/blkfront: When purging persistent grants, keep them in the buffer"
selftests/powerpc: Fix Makefiles for headers_install change
blk-mq: I/O and timer unplugs are inverted in blktrace
dax: Fix deadlock in dax_lock_mapping_entry()
x86/boot: Fix kexec booting failure in the SEV bit detection code
bcache: add separate workqueue for journal_write to avoid deadlock
drm/amd/display: Fix Edid emulation for linux
drm/amd/display: Fix Vega10 lightup on S3 resume
drm/amdgpu: Fix vce work queue was not cancelled when suspend
Revert "drm/panel: Add device_link from panel device to DRM device"
xen/blkfront: When purging persistent grants, keep them in the buffer
clocksource/drivers/timer-atmel-pit: Properly handle error cases
block: fix deadline elevator drain for zoned block devices
ACPI / hotplug / PCI: Don't scan for non-hotplug bridges if slot is not bridge
drm/syncobj: Don't leak fences when WAIT_FOR_SUBMIT is set
...
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Linus Torvalds