02 Oct, 2020
2 commits
-
Change additional instances that could use sysfs_emit and sysfs_emit_at
that the coccinelle script could not convert.o macros creating show functions with ## concatenation
o unbound sprintf uses with buf+len for start of output to sysfs_emit_at
o returns with ?: tests and sprintf to sysfs_emit
o sysfs output with struct class * not struct device * argumentsMiscellanea:
o remove unnecessary initializations around these changes
o consistently use int len for return length of show functions
o use octal permissions and not S_
o rename a few show function names so DEVICE_ATTR_ can be used
o use DEVICE_ATTR_ADMIN_RO where appropriate
o consistently use const char *output for strings
o checkpatch/style neateningSigned-off-by: Joe Perches
Link: https://lore.kernel.org/r/8bc24444fe2049a9b2de6127389b57edfdfe324d.1600285923.git.joe@perches.com
Signed-off-by: Greg Kroah-Hartman -
Convert the various sprintf fmaily calls in sysfs device show functions
to sysfs_emit and sysfs_emit_at for PAGE_SIZE buffer safety.Done with:
$ spatch -sp-file sysfs_emit_dev.cocci --in-place --max-width=80 .
And cocci script:
$ cat sysfs_emit_dev.cocci
@@
identifier d_show;
identifier dev, attr, buf;
@@ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
}@@
identifier d_show;
identifier dev, attr, buf;
@@ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
}@@
identifier d_show;
identifier dev, attr, buf;
@@ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
}@@
identifier d_show;
identifier dev, attr, buf;
expression chr;
@@ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
}@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
return len;
}@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
return len;
}@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
return len;
}@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
return len;
}@@
identifier d_show;
identifier dev, attr, buf;
expression chr;
@@ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
...
- strcpy(buf, chr);
- return strlen(buf);
+ return sysfs_emit(buf, chr);
}Signed-off-by: Joe Perches
Link: https://lore.kernel.org/r/3d033c33056d88bbe34d4ddb62afd05ee166ab9a.1600285923.git.joe@perches.com
Signed-off-by: Greg Kroah-Hartman
20 Apr, 2020
1 commit
-
SRBDS is an MDS-like speculative side channel that can leak bits from the
random number generator (RNG) across cores and threads. New microcode
serializes the processor access during the execution of RDRAND and
RDSEED. This ensures that the shared buffer is overwritten before it is
released for reuse.While it is present on all affected CPU models, the microcode mitigation
is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the
cases where TSX is not supported or has been disabled with TSX_CTRL.The mitigation is activated by default on affected processors and it
increases latency for RDRAND and RDSEED instructions. Among other
effects this will reduce throughput from /dev/urandom.* Enable administrator to configure the mitigation off when desired using
either mitigations=off or srbds=off.* Export vulnerability status via sysfs
* Rename file-scoped macros to apply for non-whitelist table initializations.
[ bp: Massage,
- s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g,
- do not read arch cap MSR a second time in tsx_fused_off() - just pass it in,
- flip check in cpu_set_bug_bits() to save an indentation level,
- reflow comments.
jpoimboe: s/Mitigated/Mitigation/ in user-visible strings
tglx: Dropped the fused off magic for now
]Signed-off-by: Mark Gross
Signed-off-by: Borislav Petkov
Signed-off-by: Thomas Gleixner
Reviewed-by: Tony Luck
Reviewed-by: Pawan Gupta
Reviewed-by: Josh Poimboeuf
Tested-by: Neelima Krishnan
31 Mar, 2020
1 commit
-
Pull core SMP updates from Thomas Gleixner:
"CPU (hotplug) updates:- Support for locked CSD objects in smp_call_function_single_async()
which allows to simplify callsites in the scheduler core and MIPS- Treewide consolidation of CPU hotplug functions which ensures the
consistency between the sysfs interface and kernel state. The low
level functions cpu_up/down() are now confined to the core code and
not longer accessible from random code"* tag 'smp-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
cpu/hotplug: Ignore pm_wakeup_pending() for disable_nonboot_cpus()
cpu/hotplug: Hide cpu_up/down()
cpu/hotplug: Move bringup of secondary CPUs out of smp_init()
torture: Replace cpu_up/down() with add/remove_cpu()
firmware: psci: Replace cpu_up/down() with add/remove_cpu()
xen/cpuhotplug: Replace cpu_up/down() with device_online/offline()
parisc: Replace cpu_up/down() with add/remove_cpu()
sparc: Replace cpu_up/down() with add/remove_cpu()
powerpc: Replace cpu_up/down() with add/remove_cpu()
x86/smp: Replace cpu_up/down() with add/remove_cpu()
arm64: hibernate: Use bringup_hibernate_cpu()
cpu/hotplug: Provide bringup_hibernate_cpu()
arm64: Use reboot_cpu instead of hardconding it to 0
arm64: Don't use disable_nonboot_cpus()
ARM: Use reboot_cpu instead of hardcoding it to 0
ARM: Don't use disable_nonboot_cpus()
ia64: Replace cpu_down() with smp_shutdown_nonboot_cpus()
cpu/hotplug: Create a new function to shutdown nonboot cpus
cpu/hotplug: Add new {add,remove}_cpu() functions
sched/core: Remove rq.hrtick_csd_pending
...
25 Mar, 2020
1 commit
-
Use separate functions for the device core to bring a CPU up and down.
Users outside the device core must use add/remove_cpu() which will take
care of extra housekeeping work like keeping sysfs in sync.Make cpu_up/down() static and replace the extra layer of indirection.
[ tglx: Removed the extra wrapper functions and adjusted function names ]
Signed-off-by: Qais Yousef
Signed-off-by: Thomas Gleixner
Link: https://lkml.kernel.org/r/20200323135110.30522-18-qais.yousef@arm.com
11 Mar, 2020
2 commits
-
Use the simpler sprintf() instead of snprintf() or scnprintf() in a
single-shot sysfs output callbacks where you are very sure that it
won't go over PAGE_SIZE buffer limit.Signed-off-by: Takashi Iwai
Link: https://lore.kernel.org/r/20200311080207.12046-3-tiwai@suse.de
Signed-off-by: Greg Kroah-Hartman -
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit. Fix it by replacing with scnprintf().Signed-off-by: Takashi Iwai
Link: https://lore.kernel.org/r/20200311080207.12046-2-tiwai@suse.de
Signed-off-by: Greg Kroah-Hartman
04 Nov, 2019
1 commit
-
Some processors may incur a machine check error possibly resulting in an
unrecoverable CPU lockup when an instruction fetch encounters a TLB
multi-hit in the instruction TLB. This can occur when the page size is
changed along with either the physical address or cache type. The relevant
erratum can be found here:https://bugzilla.kernel.org/show_bug.cgi?id=205195
There are other processors affected for which the erratum does not fully
disclose the impact.This issue affects both bare-metal x86 page tables and EPT.
It can be mitigated by either eliminating the use of large pages or by
using careful TLB invalidations when changing the page size in the page
tables.Just like Spectre, Meltdown, L1TF and MDS, a new bit has been allocated in
MSR_IA32_ARCH_CAPABILITIES (PSCHANGE_MC_NO) and will be set on CPUs which
are mitigated against this issue.Signed-off-by: Vineela Tummalapalli
Co-developed-by: Pawan Gupta
Signed-off-by: Pawan Gupta
Signed-off-by: Paolo Bonzini
Signed-off-by: Thomas Gleixner
28 Oct, 2019
1 commit
-
Add the sysfs reporting file for TSX Async Abort. It exposes the
vulnerability and the mitigation state similar to the existing files for
the other hardware vulnerabilities.Sysfs file path is:
/sys/devices/system/cpu/vulnerabilities/tsx_async_abortSigned-off-by: Pawan Gupta
Signed-off-by: Borislav Petkov
Signed-off-by: Thomas Gleixner
Tested-by: Neelima Krishnan
Reviewed-by: Mark Gross
Reviewed-by: Tony Luck
Reviewed-by: Greg Kroah-Hartman
Reviewed-by: Josh Poimboeuf
14 May, 2019
1 commit
-
Pull x86 MDS mitigations from Thomas Gleixner:
"Microarchitectural Data Sampling (MDS) is a hardware vulnerability
which allows unprivileged speculative access to data which is
available in various CPU internal buffers. This new set of misfeatures
has the following CVEs assigned:CVE-2018-12126 MSBDS Microarchitectural Store Buffer Data Sampling
CVE-2018-12130 MFBDS Microarchitectural Fill Buffer Data Sampling
CVE-2018-12127 MLPDS Microarchitectural Load Port Data Sampling
CVE-2019-11091 MDSUM Microarchitectural Data Sampling Uncacheable MemoryMDS attacks target microarchitectural buffers which speculatively
forward data under certain conditions. Disclosure gadgets can expose
this data via cache side channels.Contrary to other speculation based vulnerabilities the MDS
vulnerability does not allow the attacker to control the memory target
address. As a consequence the attacks are purely sampling based, but
as demonstrated with the TLBleed attack samples can be postprocessed
successfully.The mitigation is to flush the microarchitectural buffers on return to
user space and before entering a VM. It's bolted on the VERW
instruction and requires a microcode update. As some of the attacks
exploit data structures shared between hyperthreads, full protection
requires to disable hyperthreading. The kernel does not do that by
default to avoid breaking unattended updates.The mitigation set comes with documentation for administrators and a
deeper technical view"* 'x86-mds-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
x86/speculation/mds: Fix documentation typo
Documentation: Correct the possible MDS sysfs values
x86/mds: Add MDSUM variant to the MDS documentation
x86/speculation/mds: Add 'mitigations=' support for MDS
x86/speculation/mds: Print SMT vulnerable on MSBDS with mitigations off
x86/speculation/mds: Fix comment
x86/speculation/mds: Add SMT warning message
x86/speculation: Move arch_smt_update() call to after mitigation decisions
x86/speculation/mds: Add mds=full,nosmt cmdline option
Documentation: Add MDS vulnerability documentation
Documentation: Move L1TF to separate directory
x86/speculation/mds: Add mitigation mode VMWERV
x86/speculation/mds: Add sysfs reporting for MDS
x86/speculation/mds: Add mitigation control for MDS
x86/speculation/mds: Conditionally clear CPU buffers on idle entry
x86/kvm/vmx: Add MDS protection when L1D Flush is not active
x86/speculation/mds: Clear CPU buffers on exit to user
x86/speculation/mds: Add mds_clear_cpu_buffers()
x86/kvm: Expose X86_FEATURE_MD_CLEAR to guests
x86/speculation/mds: Add BUG_MSBDS_ONLY
...
07 Mar, 2019
2 commits
-
Pull driver core updates from Greg KH:
"Here is the big driver core patchset for 5.1-rc1More patches than "normal" here this merge window, due to some work in
the driver core by Alexander Duyck to rework the async probe
functionality to work better for a number of devices, and independant
work from Rafael for the device link functionality to make it work
"correctly".Also in here is:
- lots of BUS_ATTR() removals, the macro is about to go away
- firmware test fixups
- ihex fixups and simplification
- component additions (also includes i915 patches)
- lots of minor coding style fixups and cleanups.
All of these have been in linux-next for a while with no reported
issues"* tag 'driver-core-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (65 commits)
driver core: platform: remove misleading err_alloc label
platform: set of_node in platform_device_register_full()
firmware: hardcode the debug message for -ENOENT
driver core: Add missing description of new struct device_link field
driver core: Fix PM-runtime for links added during consumer probe
drivers/component: kerneldoc polish
async: Add cmdline option to specify drivers to be async probed
driver core: Fix possible supplier PM-usage counter imbalance
PM-runtime: Fix __pm_runtime_set_status() race with runtime resume
driver: platform: Support parsing GpioInt 0 in platform_get_irq()
selftests: firmware: fix verify_reqs() return value
Revert "selftests: firmware: remove use of non-standard diff -Z option"
Revert "selftests: firmware: add CONFIG_FW_LOADER_USER_HELPER_FALLBACK to config"
device: Fix comment for driver_data in struct device
kernfs: Allocating memory for kernfs_iattrs with kmem_cache.
sysfs: remove unused include of kernfs-internal.h
driver core: Postpone DMA tear-down until after devres release
driver core: Document limitation related to DL_FLAG_RPM_ACTIVE
PM-runtime: Take suppliers into account in __pm_runtime_set_status()
device.h: Add __cold to dev_ logging functions
... -
Add the sysfs reporting file for MDS. It exposes the vulnerability and
mitigation state similar to the existing files for the other speculative
hardware vulnerabilities.Signed-off-by: Thomas Gleixner
Reviewed-by: Greg Kroah-Hartman
Reviewed-by: Borislav Petkov
Reviewed-by: Jon Masters
Tested-by: Jon Masters
19 Feb, 2019
1 commit
-
All device objects in the driver model contain fields that control the
handling of various power management activities. However, it's not
always useful. There are few instances where pseudo devices are added
to the model just to take advantage of many other features like
kobjects, udev events, and so on. One such example is cpu devices and
their caches.The sysfs for the cpu caches are managed by adding devices with cpu
as the parent in cpu_device_create() when secondary cpu is brought
online. Generally when the secondary CPUs are hotplugged back in as part
of resume from suspend-to-ram, we call cpu_device_create() from the cpu
hotplug state machine while the cpu device associated with that CPU is
not yet ready to be resumed as the device_resume() call happens bit
later. It's not really needed to set the flag is_prepared for cpu
devices as they are mostly pseudo device and hotplug framework deals
with state machine and not managed through the cpu device.This often results in annoying warning when resuming:
Enabling non-boot CPUs ...
CPU1: Booted secondary processor
cache: parent cpu1 should not be sleeping
CPU1 is up
CPU2: Booted secondary processor
cache: parent cpu2 should not be sleeping
CPU2 is up
.... and so on.So in order to fix these kind of errors, we could just completely avoid
doing any power management related initialisations and operations if
they are not used by these devices.Add no_pm flags to indicate that the device doesn't require any sort of
PM activities and all of them can be completely skipped. We can use the
same flag to also avoid adding not used *power* sysfs entries for these
devices. For now, lets use this for cpu cache devices.Reviewed-by: Ulf Hansson
Signed-off-by: Sudeep Holla
Tested-by: Eugeniu Rosca
Signed-off-by: Rafael J. Wysocki
01 Feb, 2019
1 commit
-
Silence warnings (triggered at W=1) by adding relevant __printf
attributes.drivers/base/cpu.c:432:2: warning: function '__cpu_device_create' might be a candidate for 'gnu_printf' format attribute [-Wsuggest-attribute=format]
Signed-off-by: Mathieu Malaterre
Signed-off-by: Greg Kroah-Hartman
21 Jun, 2018
1 commit
-
L1TF core kernel workarounds are cheap and normally always enabled, However
they still should be reported in sysfs if the system is vulnerable or
mitigated. Add the necessary CPU feature/bug bits.- Extend the existing checks for Meltdowns to determine if the system is
vulnerable. All CPUs which are not vulnerable to Meltdown are also not
vulnerable to L1TF- Check for 32bit non PAE and emit a warning as there is no practical way
for mitigation due to the limited physical address bits- If the system has more than MAX_PA/2 physical memory the invert page
workarounds don't protect the system against the L1TF attack anymore,
because an inverted physical address will also point to valid
memory. Print a warning in this case and report that the system is
vulnerable.Add a function which returns the PFN limit for the L1TF mitigation, which
will be used in follow up patches for sanity and range checks.[ tglx: Renamed the CPU feature bit to L1TF_PTEINV ]
Signed-off-by: Andi Kleen
Signed-off-by: Thomas Gleixner
Reviewed-by: Josh Poimboeuf
Acked-by: Dave Hansen
03 May, 2018
1 commit
-
Add the sysfs file for the new vulerability. It does not do much except
show the words 'Vulnerable' for recent x86 cores.Intel cores prior to family 6 are known not to be vulnerable, and so are
some Atoms and some Xeon Phi.It assumes that older Cyrix, Centaur, etc. cores are immune.
Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Thomas Gleixner
Reviewed-by: Borislav Petkov
Reviewed-by: Ingo Molnar
15 Mar, 2018
1 commit
-
if device_register() returned an error! Always use put_device()
to give up the reference initialized.Signed-off-by: Arvind Yadav
Signed-off-by: Greg Kroah-Hartman
02 Feb, 2018
1 commit
-
Pull driver core updates from Greg KH:
"Here is the set of "big" driver core patches for 4.16-rc1.The majority of the work here is in the firmware subsystem, with
reworks to try to attempt to make the code easier to handle in the
long run, but no functional change. There's also some tree-wide sysfs
attribute fixups with lots of acks from the various subsystem
maintainers, as well as a handful of other normal fixes and changes.And finally, some license cleanups for the driver core and sysfs code.
All have been in linux-next for a while with no reported issues"
* tag 'driver-core-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (48 commits)
device property: Define type of PROPERTY_ENRTY_*() macros
device property: Reuse property_entry_free_data()
device property: Move property_entry_free_data() upper
firmware: Fix up docs referring to FIRMWARE_IN_KERNEL
firmware: Drop FIRMWARE_IN_KERNEL Kconfig option
USB: serial: keyspan: Drop firmware Kconfig options
sysfs: remove DEBUG defines
sysfs: use SPDX identifiers
drivers: base: add coredump driver ops
sysfs: add attribute specification for /sysfs/devices/.../coredump
test_firmware: fix missing unlock on error in config_num_requests_store()
test_firmware: make local symbol test_fw_config static
sysfs: turn WARN() into pr_warn()
firmware: Fix a typo in fallback-mechanisms.rst
treewide: Use DEVICE_ATTR_WO
treewide: Use DEVICE_ATTR_RO
treewide: Use DEVICE_ATTR_RW
sysfs.h: Use octal permissions
component: add debugfs support
bus: simple-pm-bus: convert bool SIMPLE_PM_BUS to tristate
...
15 Jan, 2018
1 commit
-
Pull x86 pti updates from Thomas Gleixner:
"This contains:- a PTI bugfix to avoid setting reserved CR3 bits when PCID is
disabled. This seems to cause issues on a virtual machine at least
and is incorrect according to the AMD manual.- a PTI bugfix which disables the perf BTS facility if PTI is
enabled. The BTS AUX buffer is not globally visible and causes the
CPU to fault when the mapping disappears on switching CR3 to user
space. A full fix which restores BTS on PTI is non trivial and will
be worked on.- PTI bugfixes for EFI and trusted boot which make sure that the user
space visible page table entries have the NX bit cleared- removal of dead code in the PTI pagetable setup functions
- add PTI documentation
- add a selftest for vsyscall to verify that the kernel actually
implements what it advertises.- a sysfs interface to expose vulnerability and mitigation
information so there is a coherent way for users to retrieve the
status.- the initial spectre_v2 mitigations, aka retpoline:
+ The necessary ASM thunk and compiler support
+ The ASM variants of retpoline and the conversion of affected ASM
code+ Make LFENCE serializing on AMD so it can be used as speculation
trap+ The RSB fill after vmexit
- initial objtool support for retpoline
As I said in the status mail this is the most of the set of patches
which should go into 4.15 except two straight forward patches still on
hold:- the retpoline add on of LFENCE which waits for ACKs
- the RSB fill after context switch
Both should be ready to go early next week and with that we'll have
covered the major holes of spectre_v2 and go back to normality"* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits)
x86,perf: Disable intel_bts when PTI
security/Kconfig: Correct the Documentation reference for PTI
x86/pti: Fix !PCID and sanitize defines
selftests/x86: Add test_vsyscall
x86/retpoline: Fill return stack buffer on vmexit
x86/retpoline/irq32: Convert assembler indirect jumps
x86/retpoline/checksum32: Convert assembler indirect jumps
x86/retpoline/xen: Convert Xen hypercall indirect jumps
x86/retpoline/hyperv: Convert assembler indirect jumps
x86/retpoline/ftrace: Convert ftrace assembler indirect jumps
x86/retpoline/entry: Convert entry assembler indirect jumps
x86/retpoline/crypto: Convert crypto assembler indirect jumps
x86/spectre: Add boot time option to select Spectre v2 mitigation
x86/retpoline: Add initial retpoline support
objtool: Allow alternatives to be ignored
objtool: Detect jumps to retpoline thunks
x86/pti: Make unpoison of pgd for trusted boot work for real
x86/alternatives: Fix optimize_nops() checking
sysfs/cpu: Fix typos in vulnerability documentation
x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC
...
08 Jan, 2018
1 commit
-
As the meltdown/spectre problem affects several CPU architectures, it makes
sense to have common way to express whether a system is affected by a
particular vulnerability or not. If affected the way to express the
mitigation should be common as well.Create /sys/devices/system/cpu/vulnerabilities folder and files for
meltdown, spectre_v1 and spectre_v2.Allow architectures to override the show function.
Signed-off-by: Thomas Gleixner
Reviewed-by: Greg Kroah-Hartman
Reviewed-by: Konrad Rzeszutek Wilk
Cc: Peter Zijlstra
Cc: Will Deacon
Cc: Dave Hansen
Cc: Linus Torvalds
Cc: Borislav Petkov
Cc: David Woodhouse
Link: https://lkml.kernel.org/r/20180107214913.096657732@linutronix.de
08 Dec, 2017
1 commit
-
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.Update the driver core files files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.Cc: Johannes Berg
Cc: "Luis R. Rodriguez"
Cc: William Breathitt Gray
Cc: Thomas Gleixner
Cc: Kate Stewart
Cc: Philippe Ombredanne
Signed-off-by: Greg Kroah-Hartman
14 Nov, 2017
1 commit
-
Pull power management updates from Rafael Wysocki:
"There are no real big ticket items here this time.The most noticeable change is probably the relocation of the OPP
(Operating Performance Points) framework to its own directory under
drivers/ as it has grown big enough for that. Also Viresh is now going
to maintain it and send pull requests for it to me, so you will see
this change in the git history going forward (but still not right
now).Another noticeable set of changes is the modifications of the PM core,
the PCI subsystem and the ACPI PM domain to allow of more integration
between system-wide suspend/resume and runtime PM. For now it's just a
way to avoid resuming devices from runtime suspend unnecessarily
during system suspend (if the driver sets a flag to indicate its
readiness for that) and in the works is an analogous mechanism to
allow devices to stay suspended after system resume.In addition to that, we have some changes related to supporting
frequency-invariant CPU utilization metrics in the scheduler and in
the schedutil cpufreq governor on ARM and changes to add support for
device performance states to the generic power domains (genpd)
framework.The rest is mostly fixes and cleanups of various sorts.
Specifics:
- Relocate the OPP (Operating Performance Points) framework to its
own directory under drivers/ and add support for power domain
performance states to it (Viresh Kumar).- Modify the PM core, the PCI bus type and the ACPI PM domain to
support power management driver flags allowing device drivers to
specify their capabilities and preferences regarding the handling
of devices with enabled runtime PM during system suspend/resume and
clean up that code somewhat (Rafael Wysocki, Ulf Hansson).- Add frequency-invariant accounting support to the task scheduler on
ARM and ARM64 (Dietmar Eggemann).- Fix PM QoS device resume latency framework to prevent "no
restriction" requests from overriding requests with specific
requirements and drop the confusing PM_QOS_FLAG_REMOTE_WAKEUP
device PM QoS flag (Rafael Wysocki).- Drop legacy class suspend/resume operations from the PM core and
drop legacy bus type suspend and resume callbacks from ARM/locomo
(Rafael Wysocki).- Add min/max frequency support to devfreq and clean it up somewhat
(Chanwoo Choi).- Rework wakeup support in the generic power domains (genpd)
framework and update some of its users accordingly (Geert
Uytterhoeven).- Convert timers in the PM core to use timer_setup() (Kees Cook).
- Add support for exposing the SLP_S0 (Low Power S0 Idle) residency
counter based on the LPIT ACPI table on Intel platforms (Srinivas
Pandruvada).- Add per-CPU PM QoS resume latency support to the ladder cpuidle
governor (Ramesh Thomas).- Fix a deadlock between the wakeup notify handler and the notifier
removal in the ACPI core (Ville Syrjälä).- Fix a cpufreq schedutil governor issue causing it to use stale
cached frequency values sometimes (Viresh Kumar).- Fix an issue in the system suspend core support code causing wakeup
events detection to fail in some cases (Rajat Jain).- Fix the generic power domains (genpd) framework to prevent the PM
core from using the direct-complete optimization with it as that is
guaranteed to fail (Ulf Hansson).- Fix a minor issue in the cpuidle core and clean it up a bit (Gaurav
Jindal, Nicholas Piggin).- Fix and clean up the intel_idle and ARM cpuidle drivers (Jason
Baron, Len Brown, Leo Yan).- Fix a couple of minor issues in the OPP framework and clean it up
(Arvind Yadav, Fabio Estevam, Sudeep Holla, Tobias Jordan).- Fix and clean up some cpufreq drivers and fix a minor issue in the
cpufreq statistics code (Arvind Yadav, Bhumika Goyal, Fabio
Estevam, Gautham Shenoy, Gustavo Silva, Marek Szyprowski, Masahiro
Yamada, Robert Jarzmik, Zumeng Chen).- Fix minor issues in the system suspend and hibernation core, in
power management documentation and in the AVS (Adaptive Voltage
Scaling) framework (Helge Deller, Himanshu Jha, Joe Perches, Rafael
Wysocki).- Fix some issues in the cpupower utility and document that Shuah
Khan is going to maintain it going forward (Prarit Bhargava, Shuah
Khan)"* tag 'pm-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (88 commits)
tools/power/cpupower: add libcpupower.so.0.0.1 to .gitignore
tools/power/cpupower: Add 64 bit library detection
intel_idle: Graceful probe failure when MWAIT is disabled
cpufreq: schedutil: Reset cached_raw_freq when not in sync with next_freq
freezer: Fix typo in freezable_schedule_timeout() comment
PM / s2idle: Clear the events_check_enabled flag
cpufreq: stats: Handle the case when trans_table goes beyond PAGE_SIZE
cpufreq: arm_big_little: make cpufreq_arm_bL_ops structures const
cpufreq: arm_big_little: make function arguments and structure pointer const
cpuidle: Avoid assignment in if () argument
cpuidle: Clean up cpuidle_enable_device() error handling a bit
ACPI / PM: Fix acpi_pm_notifier_lock vs flush_workqueue() deadlock
PM / Domains: Fix genpd to deal with drivers returning 1 from ->prepare()
cpuidle: ladder: Add per CPU PM QoS resume latency support
PM / QoS: Fix device resume latency framework
PM / domains: Rework governor code to be more consistent
PM / Domains: Remove gpd_dev_ops.active_wakeup() callback
soc: rockchip: power-domain: Use GENPD_FLAG_ACTIVE_WAKEUP
soc: mediatek: Use GENPD_FLAG_ACTIVE_WAKEUP
ARM: shmobile: pm-rmobile: Use GENPD_FLAG_ACTIVE_WAKEUP
...
08 Nov, 2017
1 commit
-
The special value of 0 for device resume latency PM QoS means
"no restriction", but there are two problems with that.First, device resume latency PM QoS requests with 0 as the
value are always put in front of requests with positive
values in the priority lists used internally by the PM QoS
framework, causing 0 to be chosen as an effective constraint
value. However, that 0 is then interpreted as "no restriction"
effectively overriding the other requests with specific
restrictions which is incorrect.Second, the users of device resume latency PM QoS have no
way to specify that *any* resume latency at all should be
avoided, which is an artificial limitation in general.To address these issues, modify device resume latency PM QoS to
use S32_MAX as the "no constraint" value and 0 as the "no
latency at all" one and rework its users (the cpuidle menu
governor, the genpd QoS governor and the runtime PM framework)
to follow these changes.Also add a special "n/a" value to the corresponding user space I/F
to allow user space to indicate that it cannot accept any resume
latencies at all for the given device.Fixes: 85dc0b8a4019 (PM / QoS: Make it possible to expose PM QoS latency constraints)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=197323
Reported-by: Reinette Chatre
Signed-off-by: Rafael J. Wysocki
Tested-by: Reinette Chatre
Tested-by: Geert Uytterhoeven
Tested-by: Tero Kristo
Reviewed-by: Ramesh Thomas
01 Nov, 2017
1 commit
-
This reverts commit 0cc2b4e5a020 (PM / QoS: Fix device resume latency PM
QoS) as it introduced regressions on multiple systems and the fix-up
in commit 2a9a86d5c813 (PM / QoS: Fix default runtime_pm device resume
latency) does not address all of them.The original problem that commit 0cc2b4e5a020 was attempting to fix
will be addressed later.Fixes: 0cc2b4e5a020 (PM / QoS: Fix device resume latency PM QoS)
Reported-by: Geert Uytterhoeven
Signed-off-by: Rafael J. Wysocki
27 Oct, 2017
1 commit
-
We want to centralize the isolation features, to be done by the housekeeping
subsystem and scheduler domain isolation is a significant part of it.No intended behaviour change, we just reuse the housekeeping cpumask
and core code.Signed-off-by: Frederic Weisbecker
Acked-by: Thomas Gleixner
Cc: Chris Metcalf
Cc: Christoph Lameter
Cc: Linus Torvalds
Cc: Luiz Capitulino
Cc: Mike Galbraith
Cc: Paul E. McKenney
Cc: Peter Zijlstra
Cc: Rik van Riel
Cc: Wanpeng Li
Link: http://lkml.kernel.org/r/1509072159-31808-11-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar
24 Oct, 2017
1 commit
-
The special value of 0 for device resume latency PM QoS means
"no restriction", but there are two problems with that.First, device resume latency PM QoS requests with 0 as the
value are always put in front of requests with positive
values in the priority lists used internally by the PM QoS
framework, causing 0 to be chosen as an effective constraint
value. However, that 0 is then interpreted as "no restriction"
effectively overriding the other requests with specific
restrictions which is incorrect.Second, the users of device resume latency PM QoS have no
way to specify that *any* resume latency at all should be
avoided, which is an artificial limitation in general.To address these issues, modify device resume latency PM QoS to
use S32_MAX as the "no constraint" value and 0 as the "no
latency at all" one and rework its users (the cpuidle menu
governor, the genpd QoS governor and the runtime PM framework)
to follow these changes.Also add a special "n/a" value to the corresponding user space I/F
to allow user space to indicate that it cannot accept any resume
latencies at all for the given device.Fixes: 85dc0b8a4019 (PM / QoS: Make it possible to expose PM QoS latency constraints)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=197323
Reported-by: Reinette Chatre
Tested-by: Reinette Chatre
Signed-off-by: Rafael J. Wysocki
Acked-by: Alex Shi
Cc: All applicable
09 Sep, 2017
1 commit
-
First, number of CPUs can't be negative number.
Second, different signnnedness leads to suboptimal code in the following
cases:1)
kmalloc(nr_cpu_ids * sizeof(X));"int" has to be sign extended to size_t.
2)
while (loff_t *pos < nr_cpu_ids)MOVSXD is 1 byte longed than the same MOV.
Other cases exist as well. Basically compiler is told that nr_cpu_ids
can't be negative which can't be deduced if it is "int".Code savings on allyesconfig kernel: -3KB
add/remove: 0/0 grow/shrink: 25/264 up/down: 261/-3631 (-3370)
function old new delta
coretemp_cpu_online 450 512 +62
rcu_init_one 1234 1272 +38
pci_device_probe 374 399 +25...
pgdat_reclaimable_pages 628 556 -72
select_fallback_rq 446 369 -77
task_numa_find_cpu 1923 1807 -116Link: http://lkml.kernel.org/r/20170819114959.GA30580@avx2
Signed-off-by: Alexey Dobriyan
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
30 Jan, 2017
1 commit
-
The cpu-dma PM QoS constraint impacts all the cpus in the system. There
is no way to let the user to choose a PM QoS constraint per cpu.The following patch exposes to the userspace a per cpu based sysfs file
in order to let the userspace to change the value of the PM QoS latency
constraint.This change is inoperative in its form and the cpuidle governors have to
take into account the per cpu latency constraint in addition to the
global cpu-dma latency constraint in order to operate properly.BTW
The pm_qos_resume_latency usage defined in
Documentation/ABI/testing/sysfs-devices-power
The /sys/devices/.../power/pm_qos_resume_latency_us attribute
contains the PM QoS resume latency limit for the given device,
which is the maximum allowed time it can take to resume the
device, after it has been suspended at run time, from a resume
request to the moment the device will be ready to process I/O,
in microseconds. If it is equal to 0, however, this means that
the PM QoS resume latency may be arbitrary.Signed-off-by: Alex Shi
Signed-off-by: Rafael J. Wysocki
31 Aug, 2016
1 commit
-
This patch could reduce one branch in this function. Also
make the code more readble.Signed-off-by: Alex Shi
Acked-by: Daniel Lezcano
To: linux-kernel@vger.kernel.org
To: Greg Kroah-Hartman
Cc: linux-pm@vger.kernel.org
Cc: Ulf Hansson
Cc: Daniel Lezcano
Signed-off-by: Greg Kroah-Hartman
21 Jan, 2016
1 commit
-
The only user of the lvalue-ness of the cpu_*_mask variables is in
drivers/base/cpu.c, and that is mostly a work-around for the fact that not
even const variables can be used in static initialization. Now that the
underlying struct cpumasks are exposed we can take their address.Signed-off-by: Rasmus Villemoes
Acked-by: Rusty Russell
Acked-by: Greg Kroah-Hartman
Cc: Michael Ellerman
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
06 Aug, 2015
1 commit
-
In commit 0db0628d9012 ("kernel: delete __cpuinit usage from all core
kernel files") cpu_up() lost its __cpuinit annotation, vanishing the
need for cpu_subsys_online() to have a __ref annotation. Just drop it
to be able to catch real section mismatches in the future.Signed-off-by: Mathias Krause
Cc: Paul Gortmaker
Signed-off-by: Greg Kroah-Hartman
20 May, 2015
2 commits
-
Currently there is no way to query which CPUs are in nohz_full
mode from userspace.Export the CPU list running in nohz_full mode in sysfs,
specifically in the file /sys/devices/system/cpu/nohz_fullThis can be used by system management tools like libvirt,
openstack, and others to ensure proper task placement.Signed-off-by: Rik van Riel
Acked-by: Mike Galbraith
Acked-by: Chris Metcalf
Signed-off-by: Greg Kroah-Hartman -
After system bootup, there is no totally reliable way to see
which CPUs are isolated, because the kernel may modify the
CPUs specified on the isolcpus= kernel command line option.Export the CPU list that actually got isolated in sysfs,
specifically in the file /sys/devices/system/cpu/isolatedThis can be used by system management tools like libvirt,
openstack, and others to ensure proper placement of tasks.Suggested-by: Li Zefan
Signed-off-by: Rik van Riel
Acked-by: Mike Galbraith
Acked-by: Chris Metcalf
Signed-off-by: Greg Kroah-Hartman
14 Feb, 2015
1 commit
-
printk and friends can now format bitmaps using '%*pb[l]'. cpumask
and nodemask also provide cpumask_pr_args() and nodemask_pr_args()
respectively which can be used to generate the two printf arguments
necessary to format the specified cpu/nodemask.* Line termination only requires one extra space at the end of the
buffer. Use PAGE_SIZE - 1 instead of PAGE_SIZE - 2 when formatting.Signed-off-by: Tejun Heo
Acked-by: Greg Kroah-Hartman
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 Nov, 2014
2 commits
-
This patch adds a new function to create per-cpu devices.
This helps in:
1. reusing the device infrastructure to create any cpu related
attributes and corresponding sysfs instead of creating and
dealing with raw kobjects directly
2. retaining the legacy path(/sys/devices/system/cpu/..) to support
existing sysfs ABI
3. avoiding to create links in the bus directory pointing to the
device as there would be per-cpu instance of these devices with
the same name since dev->bus is not populated to cpu_sysbus on
purposeSigned-off-by: Sudeep Holla
Tested-by: Stephen Boyd
Cc: Greg Kroah-Hartman
Cc: David Herrmann
Cc: Kay Sievers
Signed-off-by: Greg Kroah-Hartman -
Many sysfs *_show function use cpu{list,mask}_scnprintf to copy cpumap
to the buffer aligned to PAGE_SIZE, append '\n' and '\0' to return null
terminated buffer with newline.This patch creates a new helper function cpumap_print_to_pagebuf in
cpumask.h using newly added bitmap_print_to_pagebuf and consolidates
most of those sysfs functions using the new helper function.Signed-off-by: Sudeep Holla
Suggested-by: Stephen Boyd
Tested-by: Stephen Boyd
Acked-by: "Rafael J. Wysocki"
Acked-by: Bjorn Helgaas
Acked-by: Peter Zijlstra (Intel)
Cc: Greg Kroah-Hartman
Cc: x86@kernel.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman
19 Feb, 2014
2 commits
-
The x86 CPU feature modalias handling existed before it was reimplemented
generically. This patch aligns the x86 handling so that it
(a) reuses some more code that is now generic;
(b) uses the generic format for the modalias module metadata entry, i.e., it
now uses 'cpu:type:x86,venVVVVfamFFFFmodMMMM:feature:,XXXX,YYYY' instead of
the 'x86cpu:vendor:VVVV:family:FFFF:model:MMMM:feature:,XXXX,YYYY' that was
used before.Signed-off-by: Ard Biesheuvel
Acked-by: H. Peter Anvin
Signed-off-by: Greg Kroah-Hartman -
This patch adds support for advertising optional CPU features over udev
using the modalias, and for declaring compatibility with/dependency upon
such a feature in a module.The mapping between feature numbers and actual features should be provided
by the architecture in a file called which exports the
following functions/macros:
- cpu_feature(FEAT), a preprocessor macro that maps token FEAT to a
numeric index;
- bool cpu_have_feature(n), returning whether this CPU has support for
feature #n;
- MAX_CPU_FEATURES, an upper bound for 'n' in the previous function.The feature can then be enabled by setting CONFIG_GENERIC_CPU_AUTOPROBE
for the architecture.For instance, a module that registers its module init function using
module_cpu_feature_match(FEAT_X, module_init_function)
will be probed automatically when the CPU's support for the 'FEAT_X'
feature is advertised over udev, and will only allow the module to be
loaded by hand if the 'FEAT_X' feature is supported.Signed-off-by: Ard Biesheuvel
Signed-off-by: Greg Kroah-Hartman
01 Oct, 2013
1 commit
-
cpu_hotplug_driver_lock() serializes CPU online/offline operations
when ARCH_CPU_PROBE_RELEASE is set. This lock interface is no longer
necessary with the following reason:- lock_device_hotplug() now protects CPU online/offline operations,
including the probe & release interfaces enabled by
ARCH_CPU_PROBE_RELEASE. The use of cpu_hotplug_driver_lock() is
redundant.
- cpu_hotplug_driver_lock() is only valid when ARCH_CPU_PROBE_RELEASE
is defined, which is misleading and is only enabled on powerpc.This patch removes the cpu_hotplug_driver_lock() interface. As
a result, ARCH_CPU_PROBE_RELEASE only enables / disables the cpu
probe & release interface as intended. There is no functional change
in this patch.Signed-off-by: Toshi Kani
Reviewed-by: Nathan Fontenot
Signed-off-by: Rafael J. Wysocki
25 Sep, 2013
1 commit
-
lock_device_hotplug[_sysfs]() serializes CPU & Memory online/offline
and hotplug operations. However, this lock is not held in the debug
interfaces below that initiate CPU online/offline operations.- _debug_hotplug_cpu(), cpu0 hotplug test interface enabled by
CONFIG_DEBUG_HOTPLUG_CPU0.
- cpu_probe_store() and cpu_release_store(), cpu hotplug test interface
enabled by CONFIG_ARCH_CPU_PROBE_RELEASE.This patch changes the above interfaces to hold lock_device_hotplug().
Signed-off-by: Toshi Kani
Acked-by: Greg Kroah-Hartman
Acked-by: Yasuaki Ishimatsu
Signed-off-by: Rafael J. Wysocki