* pnp:
MAINTAINERS: Remove Bjorn Helgaas as PNP maintainer
PNP / resources: remove positive test on unsigned values
* powercap:
powercap / RAPL: add new CPU IDs
powercap / RAPL: further relax energy counter checks
* pm-runtime:
PM / runtime: Update documentation to reflect the current code flow
* pm-opp:
PM / OPP: discard duplicate OPPs
PM / OPP: Make OPP invisible to users in Kconfig
PM / OPP: fix incorrect OPP count handling in of_init_opp_table
* acpi-video:
ACPI / video: Add 4 new models to the use_native_backlight DMI list
ACPI / video: Add use native backlight quirk for the ThinkPad W530
ACPI / video: Unregister the backlight device if a raw one shows up later
backlight: Add backlight device (un)registration notification
nouveau: Don't check acpi_video_backlight_support() before registering backlight
acer-wmi: Add Aspire 5741 to video_vendor_dmi_table
acer-wmi: Switch to acpi_video_unregister_backlight
ACPI / video: Add an acpi_video_unregister_backlight function
ACPI / video: Don't register acpi_video_resume notifier without backlight devices
ACPI / video: change acpi-video brightness_switch_enabled default to 0
* acpica: (63 commits)
ACPICA: Namespace: Remove _PRP method support.
ACPI: Fix x86 regression related to early mapping size limitation
ACPICA: Tables: Add mechanism to control early table checksum verification.
ACPICA: acpidump: Fix repetitive table dump in -n mode.
ACPI: Clean up acpi_os_map/unmap_memory() to eliminate __iomem.
ACPICA: Clean up redudant definitions already defined elsewhere
ACPICA: Linux headers: Add <asm/acenv.h> to remove mis-ordered inclusion of <asm/acpi.h>
ACPICA: Linux headers: Add <acpi/platform/aclinuxex.h>
ACPICA: Linux headers: Remove ACPI_PREEMPTION_POINT() due to no usages.
ACPICA: Update version to 20140424.
ACPICA: Comment/format update, no functional change.
ACPICA: Events: Update GPE handling and initialization code.
ACPICA: Remove extraneous error message for large number of GPEs.
ACPICA: Tables: Remove old mechanism to validate if XSDT contains NULL entries.
ACPICA: Tables: Add new mechanism to skip NULL entries in RSDT and XSDT.
ACPICA: acpidump: Add support to force using RSDT.
ACPICA: Back port of improvements on exception code.
ACPICA: Back port of _PRP update.
ACPICA: acpidump: Fix truncated RSDP signature validation.
ACPICA: Linux header: Add support for stubbed externals.
...
* acpi-enumeration:
ACPI / scan: use platform bus type by default for _HID enumeration
ACPI / scan: always register ACPI LPSS scan handler
ACPI / scan: always register memory hotplug scan handler
ACPI / scan: always register container scan handler
ACPI / scan: Change the meaning of missing .attach() in scan handlers
ACPI / scan: introduce platform_id device PNP type flag
ACPI / scan: drop unsupported serial IDs from PNP ACPI scan handler ID list
ACPI / scan: drop IDs that do not comply with the ACPI PNP ID rule
ACPI / PNP: use device ID list for PNPACPI device enumeration
ACPI / scan: .match() callback for ACPI scan handlers
* acpi-pm:
ACPI / PM: Export rest of the subsys PM callbacks
ACPI / PM: Avoid resuming devices in ACPI PM domain during system suspend
ACPI / PM: Hold ACPI scan lock over the "freeze" sleep state
ACPI / PM: Export acpi_target_system_state() to modules
* acpi-battery:
ACPI / battery: wakeup the system only when necessary
power_supply: allow power supply devices registered w/o wakeup source
ACPI / battery: introduce support for POWER_SUPPLY_PROP_CAPACITY_LEVEL
ACPI / battery: Accelerate battery resume callback
* pm-sleep:
PM / hibernate: fixed typo in comment
PM / sleep: unregister wakeup source when disabling device wakeup
PM / sleep: Introduce command line argument for sleep state enumeration
PM / sleep: Use valid_state() for platform-dependent sleep states only
PM / sleep: Add state field to pm_states[] entries
PM / sleep: Update device PM documentation to cover direct_complete
PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily
PM / hibernate: Fix memory corruption in resumedelay_setup()
PM / hibernate: convert simple_strtoul to kstrtoul
PM / hibernate: Documentation: Fix script for unswapping
PM / hibernate: no kernel_power_off when pm_power_off NULL
PM / hibernate: use unsigned local variables in swsusp_show_speed()
* pm-cpuidle:
PM / suspend: Always use deepest C-state in the "freeze" sleep state
cpuidle / menu: move repeated correction factor check to init
cpuidle / menu: Return (-1) if there are no suitable states
cpuidle: Combine cpuidle_enabled() with cpuidle_select()
ARM: clps711x: Add cpuidle driver
* acpi-tables:
ACPI: Fix conflict between customized DSDT and DSDT local copy
* acpi-general:
ACPI: Add acpi_bus_attach_private_data() to attach data to ACPI handle
* acpi-processor:
ACPI / processor: Fix STARTING/DYING action in acpi_cpu_soft_notify()
ACPI / processor: Check if LAPIC is present during initialization
ACPI / ia64: introduce variable acpi_lapic into ia64
* acpi-pad:
ACPI / PAD: Use time_before() for time comparison
ACPI / PAD: call schedule() when need_resched() is true
* acpi-scan:
ACPI / scan: do not scan fixed hardware on HW-reduced platform
* acpi-hotplug:
ACPI: add dynamic_debug support
ACPI / notify: Clean up handling of hotplug events
* acpi-pci:
ACPI / PCI: Stub out pci_acpi_crs_quirks() and make it x86 specific
The _PRP method is not going to be a part of the ACPI standard. This patch
removes its support code introduced by the following commits:
1. ACPICA: Predefined names: Add support for the _PRP method.
2. ACPICA: Update for _PRP predefined name.
3. ACPICA: Add support for _LPD and _PRP methods.
4. ACPICA: Back port of _PRP update.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This change makes the busy calculation using 64 bit math which prevents
overflow for large values of aperf/mperf.
Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
Signed-off-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The PID assumes that samples are of equal time, which for a deferable
timers this is not true when the system goes idle. This causes the
PID to take a long time to converge to the min P state and depending
on the pattern of the idle load can make the P state appear stuck.
The hold-off value of three sample times before using the scaling is
to give a grace period for applications that have high performance
requirements and spend a lot of time idle, The poster child for this
behavior is the ffmpeg benchmark in the Phoronix test suite.
Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Changing to fixed point math throughout the busy calculation in
commit e66c1768 (Change busy calculation to use fixed point
math.) Introduced some inaccuracies by rounding the busy value at two
points in the calculation. This change removes roundings and moves
the rounding to the output of the PID where the calculations are
complete and the value returned as an integer.
Fixes: e66c176837 (intel_pstate: Change busy calculation to use fixed point math.)
Reported-by: Doug Smythies <dsmythies@telus.net>
Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit fcb6a15c (intel_pstate: Take core C0 time into account for core
busy calculation) introduced a regression referenced below. The issue
with "lockup" after suspend that this commit was addressing is now dealt
with in the suspend path.
Fixes: fcb6a15c2e (intel_pstate: Take core C0 time into account for core busy calculation)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=66581
Link: https://bugzilla.kernel.org/show_bug.cgi?id=75121
Reported-by: Doug Smythies <dsmythies@telus.net>
Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull powerpc fix from Ben Herrenschmidt:
"Here's just one trivial patch to wire up sys_renameat2 which I seem to
have completely missed so far.
(My test build scripts fwd me warnings but miss the ones generated for
missing syscalls)"
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: Wire renameat2() syscall
Pull MIPS fixes from Ralf Baechle:
"A fair number of fixes across the field. Nothing terribly
complicated; the one liners in below changelog should be fairly
descriptive.
Noteworthy is the SB1 change which the result of changes to binutils
resulting in one big gas warning for most files being assembled as
well as the asid_cache and branch emulation fixes which fix corruption
or possible uninteded behaviour of kernel or application code. The
remainder of fixes are more platforms or subsystem specific"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
MIPS: R46000: Fix Micro-assembler field overflow for R4600 V2
MIPS: ptrace: Avoid smp_processor_id() in preemptible code
MIPS: Lemote 2F: cs5536: mfgpt: use raw locks
MIPS: SB1: Fix excessive kernel warnings.
MIPS: RC32434: fix broken PCI resource initialization
MIPS: malta: memory.c: Initialize the 'memsize' variable
MIPS: Fix typo when reporting cache and ftlb errors for ImgTec cores
MIPS: Fix inconsistancy of __NR_Linux_syscalls value
MIPS: Fix branch emulation of branch likely instructions.
MIPS: Fix a typo error in AUDIT_ARCH definition
MIPS: Change type of asid_cache to unsigned long
Pull scheduler fixes from Ingo Molnar:
"Various fixlets, mostly related to the (root-only) SCHED_DEADLINE
policy, but also a hotplug bug fix and a fix for a NR_CPUS related
overallocation bug causing a suspend/resume regression"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix hotplug vs. set_cpus_allowed_ptr()
sched/cpupri: Replace NR_CPUS arrays
sched/deadline: Replace NR_CPUS arrays
sched/deadline: Restrict user params max value to 2^63 ns
sched/deadline: Change sched_getparam() behaviour vs SCHED_DEADLINE
sched: Disallow sched_attr::sched_policy < 0
sched: Make sched_setattr() correctly return -EFBIG
Fix a trivial comment typo (s/mam/map) in kernel/power/swap.c.
Signed-off-by: Niv Yehezkel <executerx@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The following warning message is triggered:
WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:136 __early_ioremap+0x11f/0x1f2()
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 3.15.0-rc1-00017-g86dfc6f3-dirty #298
Hardware name: Intel Corporation S2600CP/S2600CP, BIOS SE5C600.86B.99.99.x036.091920111209 09/19/2011
0000000000000009 ffffffff81b75c40 ffffffff817c627b 0000000000000000
ffffffff81b75c78 ffffffff81067b5d 000000000000007b 8000000000000563
00000000b96b20dc 0000000000000001 ffffffffff300e0c ffffffff81b75c88
Call Trace:
[<ffffffff817c627b>] dump_stack+0x45/0x56
[<ffffffff81067b5d>] warn_slowpath_common+0x7d/0xa0
[<ffffffff81067c3a>] warn_slowpath_null+0x1a/0x20
[<ffffffff81d4b9d5>] __early_ioremap+0x11f/0x1f2
[<ffffffff81d4bc5b>] early_ioremap+0x13/0x15
[<ffffffff81d2b8f3>] __acpi_map_table+0x13/0x18
[<ffffffff817b8d1a>] acpi_os_map_memory+0x26/0x14e
[<ffffffff813ff018>] acpi_tb_acquire_table+0x42/0x70
[<ffffffff813ff086>] acpi_tb_validate_table+0x27/0x37
[<ffffffff813ff0e5>] acpi_tb_verify_table+0x22/0xd8
[<ffffffff813ff6a8>] acpi_tb_install_non_fixed_table+0x60/0x1c9
[<ffffffff81d61024>] acpi_tb_parse_root_table+0x218/0x26a
[<ffffffff81d1b120>] ? early_idt_handlers+0x120/0x120
[<ffffffff81d610cd>] acpi_initialize_tables+0x57/0x59
[<ffffffff81d5f25d>] acpi_table_init+0x1b/0x99
[<ffffffff81d2bca0>] acpi_boot_table_init+0x1e/0x85
[<ffffffff81d23043>] setup_arch+0x99d/0xcc6
[<ffffffff81d1b120>] ? early_idt_handlers+0x120/0x120
[<ffffffff81d1bbbe>] start_kernel+0x8b/0x415
[<ffffffff81d1b120>] ? early_idt_handlers+0x120/0x120
[<ffffffff81d1b5ee>] x86_64_start_reservations+0x2a/0x2c
[<ffffffff81d1b72e>] x86_64_start_kernel+0x13e/0x14d
---[ end trace 11ae599a1898f4e7 ]---
when installing the following table during early stage:
ACPI: SSDT 0x00000000B9638018 07A0C4 (v02 INTEL S2600CP 00004000 INTL 20100331)
The regression is caused by the size limitation of the x86 early IO mapping.
The root cause is:
1. ACPICA doesn't split IO memory mapping and table mapping;
2. Linux x86 OSL implements acpi_os_map_memory() using a size limited fix-map
mechanism during early boot stage, which is more suitable for only IO
mappings.
This patch fixes this issue by utilizing acpi_gbl_verify_table_checksum to
disable the table mapping during early stage and enabling it again for the
late stage. In this way, the normal code path is not affected. Then after
the code related to the root cause is cleaned up, the early checksum
verification can be easily re-enabled.
A new boot parameter - acpi_force_table_verification is introduced for
the platforms that require the checksum verification to stop loading bad
tables.
This fix also covers the checksum verification for the table overrides. Now
large tables can also be overridden using the initrd override mechanism.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reported-and-tested-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It is reported that Linux x86 kernel cannot map large tables. The following
large SSDT table on such platform fails to pass checksum verification and
cannot be installed:
ACPI: SSDT 0x00000000B9638018 07A0C4 (v02 INTEL S2600CP 00004000 INTL 20100331)
It sounds strange that in the 64-bit virtual memory address space, we
cannot map a single ACPI table to do checksum verification. The root cause
is:
1. ACPICA doesn't split IO memory mapping and table mapping;
2. Linux x86 OSL implements acpi_os_map_memory() using a size limited fix-map
mechanism during early boot stage, which is more suitable for only IO
mappings.
ACPICA originally only mapped table header for signature validation, and
this header mapping is required by OSL override mechanism. There was no
checksum verification because we could not map the whole table using this
OSL. While the following ACPICA commit enforces checksum verification by
mapping the whole table during Linux boot stage and it finally triggers
this issue on some platforms:
Commit: 86dfc6f339
Subject: ACPICA: Tables: Fix table checksums verification before installation.
Before doing further cleanups for the OSL table mapping and override
implementation, this patch introduces an option for such OSPMs to
temporarily discard the checksum verification feature. It then can be
re-enabled easily when the ACPICA and the underlying OSL is ready.
This patch also deletes a comment around the limitation of mappings because
it is not correct. The limitation is not how many times we can map in the
early stage, but the OSL mapping facility may not be suitable for mapping
the ACPI tables and thus may complain us the size limitation.
The acpi_tb_verify_table() is renamed to acpi_tb_verify_temp_table() due to the
work around added, it now only applies to the table descriptor that hasn't
been installed and cannot be used in other cases. Lv Zheng.
Tested-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull core futex/rtmutex fixes from Thomas Gleixner:
"Three fixlets for long standing issues in the futex/rtmutex code
unearthed by Dave Jones syscall fuzzer:
- Add missing early deadlock detection checks in the futex code
- Prevent user space from attaching a futex to kernel threads
- Make the deadlock detector of rtmutex work again
Looks large, but is more comments than code change"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rtmutex: Fix deadlock detector for real
futex: Prevent attaching to kernel threads
futex: Add another early deadlock detection check
Pull drm fixes from Dave Airlie:
"Mostly quiet now:
i915:
fixing userspace visiblie issues, all stable marked
radeon:
one more pll fix, two crashers, one suspend/resume regression"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/radeon: Resume fbcon last
drm/radeon: only allocate necessary size for vm bo list
drm/radeon: don't allow RADEON_GEM_DOMAIN_CPU for command submission
drm/radeon: avoid crash if VM command submission isn't available
drm/radeon: lower the ref * post PLL maximum once more
drm/i915: Prevent negative relocation deltas from wrapping
drm/i915: Only copy back the modified fields to userspace from execbuffer
drm/i915: Fix dynamic allocation of physical handles
lock_parent() very much on purpose does nested locking of dentries, and
is careful to maintain the right order (lock parent first). But because
it didn't annotate the nested locking order, lockdep thought it might be
a deadlock on d_lock, and complained.
Add the proper annotation for the inner locking of the child dentry to
make lockdep happy.
Introduced by commit 046b961b45 ("shrink_dentry_list(): take parent's
->d_lock earlier").
Reported-and-tested-by: Josh Boyer <jwboyer@fedoraproject.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
So a few people complained that
commit 177cf92de4
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Tue Apr 1 22:14:59 2014 +0200
drm/crtc-helpers: fix dpms on logic
which was merged into 3.15-rc1, broke resume on radeons. Strangely git
bisect lead everyone to
commit 25f397a429
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Fri Jul 19 18:57:11 2013 +0200
drm/crtc-helper: explicit DPMS on after modeset
which was merged long ago and actually part of 3.14.
Digging deeper I've noticed (again) that the call to
drm_helper_resume_force_mode in the radeon resume handlers was a no-op
previously because everything gets shut down on suspend. radeon does
this with explicit calls to drm_helper_connector_dpms with DPMS_OFF.
But with 177c we now force the dpms state to ON, so suddenly
resume_force_mode actually forced the crtcs back on.
This is the intention of the change after all, the problem is that
radeon resumes the fbdev console layer _before_ restoring the display,
through calling fb_set_suspend. And fbcon does an immediate ->set_par,
which in turn causes the same forced mode restore to happen.
Two concurrent modeset operations didn't lead to happiness. Fix this
by delaying the fbcon resume until the end of the readeon resum
functions.
v2: Fix up a bit of the spelling fail.
References: https://lkml.org/lkml/2014/5/29/1043
References: https://lkml.org/lkml/2014/5/2/388
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=74751
Tested-by: Ken Moffat <zarniwhoop@ntlworld.com>
Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Ken Moffat <zarniwhoop@ntlworld.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@gmail.com>
this is the next pull request for stashed up radeon fixes for 3.15. This is finally calming down with only four patches in this pull request.
* 'drm-fixes-3.15' of git://people.freedesktop.org/~deathsimple/linux:
drm/radeon: only allocate necessary size for vm bo list
drm/radeon: don't allow RADEON_GEM_DOMAIN_CPU for command submission
drm/radeon: avoid crash if VM command submission isn't available
drm/radeon: lower the ref * post PLL maximum once more
Pull input subsystem fixes from Dmitry Torokhov:
"A couple of driver/build fixups and also redone quirk for Synaptics
touchpads on Lenovo boxes (now using PNP IDs instead of DMI data to
limit number of quirks)"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: synaptics - change min/max quirk table to pnp-id matching
Input: synaptics - add a matches_pnp_id helper function
Input: synaptics - T540p - unify with other LEN0034 models
Input: synaptics - add min/max quirk for the ThinkPad W540
Input: ambakmi - request a shared interrupt for AMBA KMI devices
Input: pxa27x-keypad - fix generating scancode
Input: atmel-wm97xx - only build for AVR32
Input: fix ps2/serio module dependency
because dm-cache cannot yet handle discards that span cache blocks.
Really fix a dm-mpath LOCKDEP warning that was introduced in -rc1.
Add a 'no_space_timeout' control to dm-thinp to restore the ability to
queue IO indefinitely when no data space is available. This fixes a
change in behavior that was introduced in -rc6 where the timeout
couldn't be disabled.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJTh9QAAAoJEMUj8QotnQNaNpYH/j07FeH8YlxXRcFzDi7xRVtx
luK5b9fLLlmPwW2eKSrvpI8Le4jwDvLwBmpEvN9/wyPiRDSUnYIyYdoV7RJXX2LT
wqXatObb84fwQBJ6/q8o2YMzU5ODa5XT6KGEZyD4cHdAZ9FZSwfgqhslyrBJDkSN
JBFfkXu066qw8cuYA6KFv4DwBf5eHAt5AjV/QPGd5zGXwETHLZ4ypgpwYHAGbdXa
MgfHetwtEnJYvVQex/e+9xC5IDc4/BEAhZq4n3YmEJjNq8EbX15udHmCX7S2M5pT
+9tNjUMz4j9BhoC9F8ntRz0pxWZtJK9hGojO4xoXqOCOHgp1xLQd/tHrFZS0v8E=
=u5Xd
-----END PGP SIGNATURE-----
Merge tag 'dm-3.15-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device-mapper fixes from Mike Snitzer:
"A dm-cache stable fix to split discards on cache block boundaries
because dm-cache cannot yet handle discards that span cache blocks.
Really fix a dm-mpath LOCKDEP warning that was introduced in -rc1.
Add a 'no_space_timeout' control to dm-thinp to restore the ability to
queue IO indefinitely when no data space is available. This fixes a
change in behavior that was introduced in -rc6 where the timeout
couldn't be disabled"
* tag 'dm-3.15-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm mpath: really fix lockdep warning
dm cache: always split discards on cache block boundaries
dm thin: add 'no_space_timeout' dm-thin-pool module param
While I play inhouse patches with much memory pressure on qemu-kvm,
3.14 kernel was randomly crashed. The reason was kernel stack overflow.
When I investigated the problem, the callstack was a little bit deeper
by involve with reclaim functions but not direct reclaim path.
I tried to diet stack size of some functions related with alloc/reclaim
so did a hundred of byte but overflow was't disappeard so that I encounter
overflow by another deeper callstack on reclaim/allocator path.
Of course, we might sweep every sites we have found for reducing
stack usage but I'm not sure how long it saves the world(surely,
lots of developer start to add nice features which will use stack
agains) and if we consider another more complex feature in I/O layer
and/or reclaim path, it might be better to increase stack size(
meanwhile, stack usage on 64bit machine was doubled compared to 32bit
while it have sticked to 8K. Hmm, it's not a fair to me and arm64
already expaned to 16K. )
So, my stupid idea is just let's expand stack size and keep an eye
toward stack consumption on each kernel functions via stacktrace of ftrace.
For example, we can have a bar like that each funcion shouldn't exceed 200K
and emit the warning when some function consumes more in runtime.
Of course, it could make false positive but at least, it could make a
chance to think over it.
I guess this topic was discussed several time so there might be
strong reason not to increase kernel stack size on x86_64, for me not
knowing so Ccing x86_64 maintainers, other MM guys and virtio
maintainers.
Here's an example call trace using up the kernel stack:
Depth Size Location (51 entries)
----- ---- --------
0) 7696 16 lookup_address
1) 7680 16 _lookup_address_cpa.isra.3
2) 7664 24 __change_page_attr_set_clr
3) 7640 392 kernel_map_pages
4) 7248 256 get_page_from_freelist
5) 6992 352 __alloc_pages_nodemask
6) 6640 8 alloc_pages_current
7) 6632 168 new_slab
8) 6464 8 __slab_alloc
9) 6456 80 __kmalloc
10) 6376 376 vring_add_indirect
11) 6000 144 virtqueue_add_sgs
12) 5856 288 __virtblk_add_req
13) 5568 96 virtio_queue_rq
14) 5472 128 __blk_mq_run_hw_queue
15) 5344 16 blk_mq_run_hw_queue
16) 5328 96 blk_mq_insert_requests
17) 5232 112 blk_mq_flush_plug_list
18) 5120 112 blk_flush_plug_list
19) 5008 64 io_schedule_timeout
20) 4944 128 mempool_alloc
21) 4816 96 bio_alloc_bioset
22) 4720 48 get_swap_bio
23) 4672 160 __swap_writepage
24) 4512 32 swap_writepage
25) 4480 320 shrink_page_list
26) 4160 208 shrink_inactive_list
27) 3952 304 shrink_lruvec
28) 3648 80 shrink_zone
29) 3568 128 do_try_to_free_pages
30) 3440 208 try_to_free_pages
31) 3232 352 __alloc_pages_nodemask
32) 2880 8 alloc_pages_current
33) 2872 200 __page_cache_alloc
34) 2672 80 find_or_create_page
35) 2592 80 ext4_mb_load_buddy
36) 2512 176 ext4_mb_regular_allocator
37) 2336 128 ext4_mb_new_blocks
38) 2208 256 ext4_ext_map_blocks
39) 1952 160 ext4_map_blocks
40) 1792 384 ext4_writepages
41) 1408 16 do_writepages
42) 1392 96 __writeback_single_inode
43) 1296 176 writeback_sb_inodes
44) 1120 80 __writeback_inodes_wb
45) 1040 160 wb_writeback
46) 880 208 bdi_writeback_workfn
47) 672 144 process_one_work
48) 528 112 worker_thread
49) 416 240 kthread
50) 176 176 ret_from_fork
[ Note: the problem is exacerbated by certain gcc versions that seem to
generate much bigger stack frames due to apparently bad coalescing of
temporaries and generating too many spills. Rusty saw gcc-4.6.4 using
35% more stack on the virtio path than 4.8.2 does, for example.
Minchan not only uses such a bad gcc version (4.6.3 in his case), but
some of the stack use is due to debugging (CONFIG_DEBUG_PAGEALLOC is
what causes that kernel_map_pages() frame, for example). But we're
clearly getting too close.
The VM code also seems to have excessive stack frames partly for the
same compiler reason, triggered by excessive inlining and lots of
function arguments.
We need to improve on our stack use, but in the meantime let's do this
simple stack increase too. Unlike most earlier reports, there is
nothing simple that stands out as being really horribly wrong here,
apart from the fact that the stack frames are just bigger than they
should need to be. - Linus ]
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michael S Tsirkin <mst@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: PJ Waskiewicz <pjwaskiewicz@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs dcache livelock fix from Al Viro:
"Fixes for livelocks in shrink_dentry_list() introduced by fixes to
shrink list corruption; the root cause was that trylock of parent's
->d_lock could be disrupted by d_walk() happening on other CPUs,
resulting in shrink_dentry_list() making no progress *and* the same
d_walk() being called again and again for as long as
shrink_dentry_list() doesn't get past that mess.
The solution is to have shrink_dentry_list() treat that trylock
failure not as 'try to do the same thing again', but 'lock them in the
right order'"
* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
dentry_kill() doesn't need the second argument now
dealing with the rest of shrink_dentry_list() livelock
shrink_dentry_list(): take parent's ->d_lock earlier
expand dentry_kill(dentry, 0) in shrink_dentry_list()
split dentry_kill()
lift the "already marked killed" case into shrink_dentry_list()
We have the same problem with ->d_lock order in the inner loop, where
we are dropping references to ancestors. Same solution, basically -
instead of using dentry_kill() we use lock_parent() (introduced in the
previous commit) to get that lock in a safe way, recheck ->d_count
(in case if lock_parent() has ended up dropping and retaking ->d_lock
and somebody managed to grab a reference during that window), trylock
the inode->i_lock and use __dentry_kill() to do the rest.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The cause of livelocks there is that we are taking ->d_lock on
dentry and its parent in the wrong order, forcing us to use
trylock on the parent's one. d_walk() takes them in the right
order, and unfortunately it's not hard to create a situation
when shrink_dentry_list() can't make progress since trylock
keeps failing, and shrink_dcache_parent() or check_submounts_and_drop()
keeps calling d_walk() disrupting the very shrink_dentry_list() it's
waiting for.
Solution is straightforward - if that trylock fails, let's unlock
the dentry itself and take locks in the right order. We need to
stabilize ->d_parent without holding ->d_lock, but that's doable
using RCU. And we'd better do that in the very beginning of the
loop in shrink_dentry_list(), since the checks on refcount, etc.
would need to be redone anyway.
That deals with a half of the problem - killing dentries on the
shrink list itself. Another one (dropping their parents) is
in the next commit.
locking parent is interesting - it would be easy to do rcu_read_lock(),
lock whatever we think is a parent, lock dentry itself and check
if the parent is still the right one. Except that we need to check
that *before* locking the dentry, or we are risking taking ->d_lock
out of order. Fortunately, once the D1 is locked, we can check if
D2->d_parent is equal to D1 without the need to lock D2; D2->d_parent
can start or stop pointing to D1 only under D1->d_lock, so taking
D1->d_lock is enough. In other words, the right solution is
rcu_read_lock/lock what looks like parent right now/check if it's
still our parent/rcu_read_unlock/lock the child.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Because of the growing demand for enumerating ACPI devices to
platform bus, change the code to enumerate ACPI device objects to
platform bus by default. Namely, create platform devices for the
ACPI device objects that
1. Have pnp.type.platform_id set (device objects with _HID currently).
2. Do not have a scan handler attached.
3. Are not SPI/I2C slave devices (that should be enumerated to the
appropriate buses bus by their parent).
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[rjw: Subject and changelog, rebase and code cleanup]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Prevent platform devices from being created for ACPI LPSS devices
if CONFIG_X86_INTEL_LPSS is unset by compiling out the LPSS scan
handler's callbacks only in that case and still compiling its device
ID list in and registering the scan handler in either case.
This change is based on a prototype from Zhang Rui.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Prevent platform devices from being created for ACPI memory device
objects if CONFIG_ACPI_HOTPLUG_MEMORY is unset by compiling out the
memory hotplug scan handler's callbacks only in that case and still
compiling its device ID list in and registering the scan handler in
either case.
Also unset the memory hotplug scan handler's .attach() callback
if acpi_no_memhotplug is set, but still register the scan handler to
avoid creating platform devices for ACPI memory devices in that case
too.
This change is based on a prototype from Zhang Rui.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Prevent platform devices from being created for ACPI containers
if CONFIG_ACPI_CONTAINER is unset by compiling out the container
scan handler's callbacks only in that case and still compiling
its device ID list in and registering the scan handler in either
case.
This change is based on a prototype from Zhang Rui.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Currently, some scan handlers can be compiled out entirely, which
leaves the device objects they normally attach to without a scan
handler. This isn't a problem as long as we don't have any default
enumeration mechanism that applies to all devices without a scan
handler. However, if such a default enumeration is added, it still
should not be applied to devices that are normally attached to by
scan handlers, because that may result in creating "physical" device
objects of a wrong type for them.
Since we are going to create platform device objects for all ACPI
device objects with pnp.type.platform_id set by default, clear
pnp.type.platform_id where there is a matching scan handler without
an .attach() callback and otherwise simply treat that scan handler
as though the .attach() callback was present but always returned 0.
This will allow us to compile out scan handler callbacks and leave
the device ID lists used by them so as to prevent creating platform
device objects for the matching ACPI devices.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Only certain types of ACPI device objects can be enumerated as
platform devices, so in order to distinguish them from the others
introduce a new ACPI device PNP type flag, platform_id, and set it
for devices with a valid _HID to start with.
This change is based on a Zhang Rui's prototype.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The "serial" PNP driver supports some "unknown" PNP modems
(PNPCXXX/PNPDXXX) by matching magic strings in the PNP device name
or the PNP device card name.
ACPI enumerated PNP devices neither are PNP cards, nor have those
magic strings in device names, so this mechamism never actually works
for ACPI enumerated PNPCXXX/PNPDXXX devices.
Consequently, it is safe to remove those two IDs from the PNP ACPI scan
handler's device ID list.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[rjw: Subject and changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The PNP ACPI scan handler device ID list includes all the IDs from
all of the struct pnp_device_id instances in the tree, but some of
them do not follow the ACPI PNP ID rule (3 letters + 4 hex digits).
For those IDs, the coressponding devices will never be enumerated
via ACPI, so it is safe to remove them from the PNP ACPI ID list.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[rjw: Subject and changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
ACPI can be used to enumerate PNP devices, but the code does not
handle this in the right way currently. Namely, if an ACPI device
object
1. Has a _CRS method,
2. Has an identification of
"three capital characters followed by four hex digits",
3. Is not in the excluded IDs list,
it will be enumerated to PNP bus (that is, a PNP device object will
be create for it). This means that, actually, the PNP bus type is
used as the default bus type for enumerating _HID devices in ACPI.
However, more and more _HID devices need to be enumerated to the
platform bus instead (that is, platform device objects need to be
created for them). As a result, the device ID list in acpi_platform.c
is used to enforce creating platform device objects rather than PNP
device objects for matching devices. That list has been continuously
growing recently, unfortunately, and it is pretty much guaranteed to
grow even more in the future.
To address that problem it is better to enumerate _HID devices
as platform devices by default. To this end, change the way of
enumerating PNP devices by adding a PNP ACPI scan handler that
will use a device ID list to create PNP devices for the ACPI
device objects whose device IDs are present in that list.
The initial device ID list in the PNP ACPI scan handler contains
all of the pnp_device_id strings from all the existing PNP drivers,
so this change should be transparent to the PNP core and all of the
PNP drivers. Still, in the future it should be possible to reduce
its size by converting PNP drivers that need not be PNP for any
technical reasons into platform drivers.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[rjw: Rewrote the changelog, modified the PNP ACPI scan handler code]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
