With frame pointers, when a task is interrupted, its stack is no longer
completely reliable because the function could have been interrupted
before it had a chance to save the previous frame pointer on the stack.
So the caller of the interrupted function could get skipped by a stack
trace.
This is problematic for live patching, which needs to know whether a
stack trace of a sleeping task can be relied upon. There's currently no
way to detect if a sleeping task was interrupted by a page fault
exception or preemption before it went to sleep.
Another issue is that when dumping the stack of an interrupted task, the
unwinder has no way of knowing where the saved pt_regs registers are, so
it can't print them.
This solves those issues by encoding the pt_regs pointer in the frame
pointer on entry from an interrupt or an exception.
This patch also updates the unwinder to be able to decode it, because
otherwise the unwinder would be broken by this change.
Note that this causes a change in the behavior of the unwinder: each
instance of a pt_regs on the stack is now considered a "frame". So
callers of unwind_get_return_address() will now get an occasional
'regs->ip' address that would have previously been skipped over.
Suggested-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/8b9f84a21e39d249049e0547b559ff8da0df0988.1476973742.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When core_kernel_text() is used to determine whether an address on a
task's stack trace is a kernel text address, it incorrectly returns
false for early text addresses for the head code between the _text and
_stext markers. Among other things, this can cause the unwinder to
behave incorrectly when unwinding to x86 head code.
Head code is text code too, so mark it as such. This seems to match the
intent of other users of the _stext symbol, and it also seems consistent
with what other architectures are already doing.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/789cf978866420e72fa89df44aa2849426ac378d.1474480779.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thanks to all the recent x86 entry code refactoring, most tasks' kernel
stacks start at the same offset right below their saved pt_regs,
regardless of which syscall was used to enter the kernel. That creates
a nice convention which makes it straightforward to identify the end of
the stack, which can be useful for the unwinder to verify the stack is
sane.
However, the boot CPU's idle "swapper" task doesn't follow that
convention. Fix that by starting its stack at a sizeof(pt_regs) offset
from the end of the stack page.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/81aee3beb6ed88e44f1bea6986bb7b65c368f77a.1474480779.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The frame at the end of each idle task stack has a zeroed return
address. This is inconsistent with real task stacks, which have a real
return address at that spot. This inconsistency can be confusing for
stack unwinders. It also hides useful information about what asm code
was involved in calling into C.
Make it a real address by using the side effect of a call instruction to
push the instruction pointer on the stack.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/f59593ae7b15d5126f872b0a23143173d28aa32d.1474480779.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There are two different pieces of code for starting a CPU: start_cpu0()
and the end of secondary_startup_64(). They're identical except for the
stack setup. Combine the common parts into a shared start_cpu()
function.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1d692ffa62fcb3cc835a5b254e953f2d9bab3549.1474480779.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On 32-bit kernels, the initial idle stack calculation doesn't take into
account the TOP_OF_KERNEL_STACK_PADDING, making the stack end address
inconsistent with other tasks on 32-bit.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/6cf569410bfa84cf923902fc4d628444cace94be.1474480779.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The frame at the end of each idle task stack is inconsistent with real
task stacks, which have a stack frame header and a real return address
before the pt_regs area. This inconsistency can be confusing for stack
unwinders. It also hides useful information about what asm code was
involved in calling into C.
Fix that by changing the initial code jumps to calls. Also add infinite
loops after the calls to make it clear that the calls don't return, and
to hang if they do.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/2588f34b6fbac4ae6f6f9ead2a78d7f8d58a6341.1474480779.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thanks to all the recent x86 entry code refactoring, most tasks' kernel
stacks start at the same offset right below their saved pt_regs,
regardless of which syscall was used to enter the kernel. That creates
a nice convention which makes it straightforward to identify the end of
the stack, which can be useful for the unwinder to verify the stack is
sane.
Calling schedule_tail() directly breaks that convention because its an
asmlinkage function so its argument has to be pushed on the stack. Add
a wrapper which creates a proper "end of stack" frame header before the
call.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/ecafcd882676bf48ceaf50483782552bb98476e5.1474480779.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The 'error_code' label is awkwardly named, especially when it shows up
in a stack trace. Move it to its own local function and rename it to
'common_exception', analagous to the existing 'common_interrupt'.
This also makes related stack traces more sensible.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/cca1734a93e52799556d946281b32468f9b93950.1474480779.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add the local label prefix to all non-function named labels in head_32.S
and entry_32.S. In addition to decluttering the symbol table, it also
will help stack traces to be more sensible. For example, the last
reported function in the idle task stack trace will be startup_32_smp()
instead of is486().
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/14f9f7afd478b23a762f40734da1a57c0c273f6e.1474480779.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix a Kconfig issue leading potential link failure, and
add a DMI match for an existing quirk.
asus-wmi:
- add SERIO_I8042 dependency
ideapad-laptop:
- Add Lenovo Yoga 910-13IKB to no_hw_rfkill dmi list
-----BEGIN PGP SIGNATURE-----
iQEcBAABAgAGBQJYB7xbAAoJEKbMaAwKp364JZ0IAKbnhIY5UuwIxbShgbKR6o/H
QOosQwHx+ZzGW4jtYRCEMU1uJH5B4CESMlUzPMJSqkpAz4yZyvaLnMnNL1C2QQkV
vzn92owyeuNm1VmWxCBL5EbowcMQyAlWtZik9JEwz9G1nlSOlgOhjH4mfugePJLr
2sCGyfenzXM3otTTB5eGqKg6+4upmf/H8I3HQlu8TUnISslFHahf9czOaFWKwrK6
tm4nWHzx/nx4PcPQm+EvWT5mlsg/+DhFtyzJIqPZypmBuXR2MRaomqe8AugAXcst
iVHxve7CWrw/Oiaa4tESdS/P2KhnLzVbDjUaOyAMLyBu670xBnlieH6Q4jJjd4Y=
=yZrl
-----END PGP SIGNATURE-----
Merge tag 'platform-drivers-x86-v4.9-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86
Pull x86 platform driver fixes from Darren Hart:
"Fix a Kconfig issue leading potential link failure, and add a DMI
match for an existing quirk.
asus-wmi:
- add SERIO_I8042 dependency
ideapad-laptop:
- Add Lenovo Yoga 910-13IKB to no_hw_rfkill dmi list"
* tag 'platform-drivers-x86-v4.9-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86:
platform/x86: asus-wmi: add SERIO_I8042 dependency
platform/x86: ideapad-laptop: Add Lenovo Yoga 910-13IKB to no_hw_rfkill dmi list
other subsystems.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)
iQEcBAABAgAGBQJYB69cAAoJELcQ+SIFb8Hau0IH/3UBLH7YvoPomqZU3OhPzLMr
49HgPJEcDNYv6piU+VlT3RK16GJcjobJF6OFlbNvCqvt/IqnrR3eX4LD2Tv0d7z1
XlLQ0Re9pL3Lbe4Mo3YdiZrh+Zv6yzMsQqpbUSf298VvwZ84AoLWVTJ+oobGTTP/
77PPyZiRxgVsC+3YERk49Af48xpt3Bm2pNhT1wutf7+OW2aatA/v9LIsz9zAzhRN
gULZ9l+9w2pT9sVT6ho7w3Xm00kvGr/MW3AjbnMaHey3cpjkvj8VGmF0X6/d/4ct
Tqygpe1nMXjbIvQ1Zg3uH3qbjo8N27ajoQaaOaWa80SGc2Urf8zDswCcagljCDU=
=Lqsd
-----END PGP SIGNATURE-----
Merge tag 'sh-for-4.9' of git://git.libc.org/linux-sh
Pull arch/sh updates from Rich Felker:
"Minor changes to improve J2 support and match Kconfig expectations of
other subsystems"
* tag 'sh-for-4.9' of git://git.libc.org/linux-sh:
sh: add earlycon support to j2_defconfig
sh: add Kconfig option for J-Core SoC core drivers
sh: support CPU_J2 when compiler lacks -mj2
Pull scheduler fix from Ingo Molnar:
"This fixes a group scheduling related performance/interactivity
regression introduced in v4.8, which affects certain hardware
environments where cpu_possible_mask != cpu_present_mask"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Fix incorrect task group ->load_avg
Pull HID fixes from Jiri Kosina:
- hid-dr regression fix for certain dragonrise gamepads (device ID
0079:0006), from Ioan-Adrian Ratiu
- dma-on-stack fix for hid-led driver, from Heiner Kallweit
- quirk for Akai MIDImix device
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
HID: add quirk for Akai MIDImix.
Revert "HID: dragonrise: fix HID Descriptor for 0x0006 PID"
HID: hid-dr: add input mapping for axis selection
HID: hid-led: fix issue with transfer buffer not being dma capable
- A bunch of barnsjukdomar/kinderkrankheiten/maladie infantile
in the Aspeed driver. (Why doesn't English have a word for this?)
- Fix a lockdep bug on the Intel BayTrail.
- Fix a few special laptop issues on the Intel pin controller
solving suspend issues.
-----BEGIN PGP SIGNATURE-----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=ODoY
-----END PGP SIGNATURE-----
Merge tag 'pinctrl-v4.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull first round of pin control fixes from Linus Walleij:
- a bunch of barnsjukdomar/kinderkrankheiten/maladie infantile in the
Aspeed driver. (Why doesn't English have a word for this?)
[ Maybe "teething problems" is the closest English idiom? - Linus T ]
- fix a lockdep bug on the Intel BayTrail.
- fix a few special laptop issues on the Intel pin controller solving
suspend issues.
* tag 'pinctrl-v4.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: intel: Only restore pins that are used by the driver
pinctrl: baytrail: Fix lockdep
pinctrl: aspeed-g5: Fix pin association of SPI1 function
pinctrl: aspeed-g5: Fix GPIOE1 typo
pinctrl: aspeed-g5: Fix names of GPID2 pins
pinctrl: aspeed: "Not enabled" is a significant mux state
We have a fairly common pattern where you print several things as
continuations on one single line in a loop, and then at the end you do
printk(KERN_CONT "\n");
to flush the buffered output.
But if the output was flushed by something else (concurrent printk
activity, or just system logging), we don't want that final flushing to
just print an empty line.
So just suppress empty continuation lines when they couldn't be merged
into the line they are a continuation of.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge the gup_flags cleanups from Lorenzo Stoakes:
"This patch series adjusts functions in the get_user_pages* family such
that desired FOLL_* flags are passed as an argument rather than
implied by flags.
The purpose of this change is to make the use of FOLL_FORCE explicit
so it is easier to grep for and clearer to callers that this flag is
being used. The use of FOLL_FORCE is an issue as it overrides missing
VM_READ/VM_WRITE flags for the VMA whose pages we are reading
from/writing to, which can result in surprising behaviour.
The patch series came out of the discussion around commit 38e0885465
("mm: check VMA flags to avoid invalid PROT_NONE NUMA balancing"),
which addressed a BUG_ON() being triggered when a page was faulted in
with PROT_NONE set but having been overridden by FOLL_FORCE.
do_numa_page() was run on the assumption the page _must_ be one marked
for NUMA node migration as an actual PROT_NONE page would have been
dealt with prior to this code path, however FOLL_FORCE introduced a
situation where this assumption did not hold.
See
https://marc.info/?l=linux-mm&m=147585445805166
for the patch proposal"
Additionally, there's a fix for an ancient bug related to FOLL_FORCE and
FOLL_WRITE by me.
[ This branch was rebased recently to add a few more acked-by's and
reviewed-by's ]
* gup_flag-cleanups:
mm: replace access_process_vm() write parameter with gup_flags
mm: replace access_remote_vm() write parameter with gup_flags
mm: replace __access_remote_vm() write parameter with gup_flags
mm: replace get_user_pages_remote() write/force parameters with gup_flags
mm: replace get_user_pages() write/force parameters with gup_flags
mm: replace get_vaddr_frames() write/force parameters with gup_flags
mm: replace get_user_pages_locked() write/force parameters with gup_flags
mm: replace get_user_pages_unlocked() write/force parameters with gup_flags
mm: remove write/force parameters from __get_user_pages_unlocked()
mm: remove write/force parameters from __get_user_pages_locked()
mm: remove gup_flags FOLL_WRITE games from __get_user_pages()
This removes the 'write' argument from access_process_vm() and replaces
it with 'gup_flags' as use of this function previously silently implied
FOLL_FORCE, whereas after this patch callers explicitly pass this flag.
We make this explicit as use of FOLL_FORCE can result in surprising
behaviour (and hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes the 'write' argument from access_remote_vm() and replaces
it with 'gup_flags' as use of this function previously silently implied
FOLL_FORCE, whereas after this patch callers explicitly pass this flag.
We make this explicit as use of FOLL_FORCE can result in surprising
behaviour (and hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes the 'write' argument from __access_remote_vm() and replaces
it with 'gup_flags' as use of this function previously silently implied
FOLL_FORCE, whereas after this patch callers explicitly pass this flag.
We make this explicit as use of FOLL_FORCE can result in surprising
behaviour (and hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes the 'write' and 'force' from get_user_pages_remote() and
replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in
callers as use of this flag can result in surprising behaviour (and
hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes the 'write' and 'force' from get_user_pages() and replaces
them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers
as use of this flag can result in surprising behaviour (and hence bugs)
within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes the 'write' and 'force' from get_vaddr_frames() and
replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in
callers as use of this flag can result in surprising behaviour (and
hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes the 'write' and 'force' use from get_user_pages_locked()
and replaces them with 'gup_flags' to make the use of FOLL_FORCE
explicit in callers as use of this flag can result in surprising
behaviour (and hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A scheduler performance regression has been reported by Joseph Salisbury,
which he bisected back to:
3d30544f02 ("sched/fair: Apply more PELT fixes)
The regression triggers when several levels of task groups are involved
(read: SystemD) and cpu_possible_mask != cpu_present_mask.
The root cause is that group entity's load (tg_child->se[i]->avg.load_avg)
is initialized to scale_load_down(se->load.weight). During the creation of
a child task group, its group entities on possible CPUs are attached to
parent's cfs_rq (tg_parent) and their loads are added to the parent's load
(tg_parent->load_avg) with update_tg_load_avg().
But only the load on online CPUs will then be updated to reflect real load,
whereas load on other CPUs will stay at the initial value.
The result is a tg_parent->load_avg that is higher than the real load, the
weight of group entities (tg_parent->se[i]->load.weight) on online CPUs is
smaller than it should be, and the task group gets a less running time than
what it could expect.
( This situation can be detected with /proc/sched_debug. The ".tg_load_avg"
of the task group will be much higher than sum of ".tg_load_avg_contrib"
of online cfs_rqs of the task group. )
The load of group entities don't have to be intialized to something else
than 0 because their load will increase when an entity is attached.
Reported-by: Joseph Salisbury <joseph.salisbury@canonical.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@vger.kernel.org> # 4.8.x
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: joonwoop@codeaurora.org
Fixes: 3d30544f02 ("sched/fair: Apply more PELT fixes)
Link: http://lkml.kernel.org/r/1476881123-10159-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
f2fs_gc. It was newly introduced in 4.9-rc1.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=1MpQ
-----END PGP SIGNATURE-----
Merge tag 'for-f2fs-4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs bugfix from Jaegeuk Kim:
"This fixes a bug which referenced the wrong pointer, sum_page, in
f2fs_gc. It was newly introduced in 4.9-rc1.
* tag 'for-f2fs-4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
f2fs: fix wrong sum_page pointer in f2fs_gc
This removes the 'write' and 'force' use from get_user_pages_unlocked()
and replaces them with 'gup_flags' to make the use of FOLL_FORCE
explicit in callers as use of this flag can result in surprising
behaviour (and hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes the redundant 'write' and 'force' parameters from
__get_user_pages_unlocked() to make the use of FOLL_FORCE explicit in
callers as use of this flag can result in surprising behaviour (and
hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes the redundant 'write' and 'force' parameters from
__get_user_pages_locked() to make the use of FOLL_FORCE explicit in
callers as use of this flag can result in surprising behaviour (and
hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is an ancient bug that was actually attempted to be fixed once
(badly) by me eleven years ago in commit 4ceb5db975 ("Fix
get_user_pages() race for write access") but that was then undone due to
problems on s390 by commit f33ea7f404 ("fix get_user_pages bug").
In the meantime, the s390 situation has long been fixed, and we can now
fix it by checking the pte_dirty() bit properly (and do it better). The
s390 dirty bit was implemented in abf09bed3c ("s390/mm: implement
software dirty bits") which made it into v3.9. Earlier kernels will
have to look at the page state itself.
Also, the VM has become more scalable, and what used a purely
theoretical race back then has become easier to trigger.
To fix it, we introduce a new internal FOLL_COW flag to mark the "yes,
we already did a COW" rather than play racy games with FOLL_WRITE that
is very fundamental, and then use the pte dirty flag to validate that
the FOLL_COW flag is still valid.
Reported-and-tested-by: Phil "not Paul" Oester <kernel@linuxace.com>
Acked-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Michal Hocko <mhocko@suse.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull timer fixlet from Ingo Molnar:
"Remove an unused variable"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
alarmtimer: Remove unused but set variable
Pull scheduler fix from Ingo Molnar:
"Fix a crash that can trigger when racing with CPU hotplug: we didn't
use sched-domains data structures carefully enough in select_idle_cpu()"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Fix sched domains NULL dereference in select_idle_sibling()
Pull perf fixes from Ingo Molnar:
"Four tooling fixes, two kprobes KASAN related fixes and an x86 PMU
driver fix/cleanup"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf jit: Fix build issue on Ubuntu
perf jevents: Handle events including .c and .o
perf/x86/intel: Remove an inconsistent NULL check
kprobes: Unpoison stack in jprobe_return() for KASAN
kprobes: Avoid false KASAN reports during stack copy
perf header: Set nr_numa_nodes only when we parsed all the data
perf top: Fix refreshing hierarchy entries on TUI
Pull misc fixes from Ingo Molnar:
"A CPU hotplug debuggability fix and three objtool false positive
warnings fixes for new GCC6 code generation patterns"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu/hotplug: Use distinct name for cpu_hotplug.dep_map
objtool: Skip all "unreachable instruction" warnings for gcov kernels
objtool: Improve rare switch jump table pattern detection
objtool: Support '-mtune=atom' stack frame setup instruction
- catch an initialization error in the packet sniffer nosy
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=YbZK
-----END PGP SIGNATURE-----
Merge tag 'firewire-update' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394
Pull firewire fixlet from Stefan Richter:
"IEEE 1394 subsystem patch: catch an initialization error in the packet
sniffer nosy"
* tag 'firewire-update' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
firewire: nosy: do not ignore errors in ioremap_nocache()
-----BEGIN PGP SIGNATURE-----
iQIcBAABAgAGBQJYBG8+AAoJEAx081l5xIa+xvIP/1crQ/9k2JJJypYmCgRzWwEp
PHXF7+z7spLraGGcQgcMj3XZxZbRk9kvzOxrtGdPFW6YVH7j+y3A5BFXx2S5WePW
Mtqw00dCJ/5jW2zlf9UX0TL3DDFPsFzS+MG13ZjSeljuJsBRgrA61G4iH3PRSkqp
NFEEQzh34L8ShsFA/WP1YnFv0DooUEbnYh6WyKLLACJQbN1PVcGjTN5ZoEpSViyc
XBK4mSOeOkPJlP4xzTGB9nyYCWpacPINSVASdWRvHPZaAO+X4tlMSQ/lHrXE41nY
+UliTMY5RSDP6Gyh94hmzkMO8Y7SNg3npE/ckk3vJnP8PvM829ossES6tMUcT/tw
3SqN5kL6u5TAnGL96rdsRODGwkSOOaPLPbO85FIhmpicaYFUGaIFD3uK2vfOH+yR
YGi8Bh3/7SLnMV4ig5c+9V8QFG/hkBK8m1NrB3Z2YJUjeWWgngZapXeYIHi00U90
BqL4e8ZtL+ko5DrxVdFVshCFlvkM28UEOwtp3Sq1L21OW0pk8QESxLye9yBMgb65
m4lGFb+4pXr+PuiH4k1yENIwNsqQc7l6FWv05H4AaqgIbDQtM41JFvmRMG8OAabP
aMRkz87ucZoMM6LrLv4+RvdiZnWoTwmNGQWysgpquECUley/Yt8DDaIrlQWaNAYF
UwA0Naq6rjLaNcLkwIgG
=sGp1
-----END PGP SIGNATURE-----
Merge tag 'drm-fixes-for-v4.9-rc2' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"Just had a couple of amdgpu fixes and one core fix I wanted to get out
early to fix some regressions.
I'm sure I'll have more stuff this week for -rc2"
* tag 'drm-fixes-for-v4.9-rc2' of git://people.freedesktop.org/~airlied/linux: (22 commits)
drm: Print device information again in debugfs
drm/amd/powerplay: fix bug stop dpm can't work on Vi.
drm/amd/powerplay: notify smu no display by default.
drm/amdgpu/dpm: implement thermal sensor for CZ/ST
drm/amdgpu/powerplay: implement thermal sensor for CZ/ST
drm/amdgpu: disable smu hw first on tear down
drm/amdgpu: fix amdgpu_need_full_reset (v2)
drm/amdgpu/si_dpm: Limit clocks on HD86xx part
drm/amd/powerplay: fix static checker warnings in smu7_hwmgr.c
drm/amdgpu: potential NULL dereference in debugfs code
drm/amd/powerplay: fix static checker warnings in smu7_hwmgr.c
drm/amd/powerplay: fix static checker warnings in iceland_smc.c
drm/radeon: change vblank_time's calculation method to reduce computational error.
drm/amdgpu: change vblank_time's calculation method to reduce computational error.
drm/amdgpu: clarify UVD/VCE special handling for CG
drm/amd/amdgpu: enable clockgating only after late init
drm/radeon: allow TA_CS_BC_BASE_ADDR on SI
drm/amdgpu: initialize the context reset_counter in amdgpu_ctx_init
drm/amdgpu/gfx8: fix CGCG_CGLS handling
drm/radeon: fix modeset tear down code
...
Dell XPS 13 (and maybe some others) uses a GPIO (CPU_GP_1) during suspend
to explicitly disable USB touchscreen interrupt. This is done to prevent
situation where the lid is closed the touchscreen is left functional.
The pinctrl driver (wrongly) assumes it owns all pins which are owned by
host and not locked down. It is perfectly fine for BIOS to use those pins
as it is also considered as host in this context.
What happens is that when the lid of Dell XPS 13 is closed, the BIOS
configures CPU_GP_1 low disabling the touchscreen interrupt. During resume
we restore all host owned pins to the known state which includes CPU_GP_1
and this overwrites what the BIOS has programmed there causing the
touchscreen to fail as no interrupts are reaching the CPU anymore.
Fix this by restoring only those pins we know are explicitly requested by
the kernel one way or other.
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=176361
Reported-by: AceLan Kao <acelan.kao@canonical.com>
Tested-by: AceLan Kao <acelan.kao@canonical.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Initialize the spinlock before using it.
INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.8.0-dwc-bisect #4
Hardware name: Intel Corp. VALLEYVIEW C0 PLATFORM/BYT-T FFD8, BIOS BLAKFF81.X64.0088.R10.1403240443 FFD8_X64_R_2014_13_1_00 03/24/2014
0000000000000000 ffff8800788ff770 ffffffff8133d597 0000000000000000
0000000000000000 ffff8800788ff7e0 ffffffff810cfb9e 0000000000000002
ffff8800788ff7d0 ffffffff8205b600 0000000000000002 ffff8800788ff7f0
Call Trace:
[<ffffffff8133d597>] dump_stack+0x67/0x90
[<ffffffff810cfb9e>] register_lock_class+0x52e/0x540
[<ffffffff810d2081>] __lock_acquire+0x81/0x16b0
[<ffffffff810cede1>] ? save_trace+0x41/0xd0
[<ffffffff810d33b2>] ? __lock_acquire+0x13b2/0x16b0
[<ffffffff810cf05a>] ? __lock_is_held+0x4a/0x70
[<ffffffff810d3b1a>] lock_acquire+0xba/0x220
[<ffffffff8136f1fe>] ? byt_gpio_get_direction+0x3e/0x80
[<ffffffff81631567>] _raw_spin_lock_irqsave+0x47/0x60
[<ffffffff8136f1fe>] ? byt_gpio_get_direction+0x3e/0x80
[<ffffffff8136f1fe>] byt_gpio_get_direction+0x3e/0x80
[<ffffffff813740a9>] gpiochip_add_data+0x319/0x7d0
[<ffffffff81631723>] ? _raw_spin_unlock_irqrestore+0x43/0x70
[<ffffffff8136fe3b>] byt_pinctrl_probe+0x2fb/0x620
[<ffffffff8142fb0c>] platform_drv_probe+0x3c/0xa0
...
Based on the diff it looks like the problem was introduced in
commit 71e6ca61e8 ("pinctrl: baytrail: Register pin control handling")
but I wasn't able to verify that empirically as the parent commit
just oopsed when I tried to boot it.
Cc: Cristina Ciocan <cristina.ciocan@intel.com>
Cc: stable@vger.kernel.org
Fixes: 71e6ca61e8 ("pinctrl: baytrail: Register pin control handling")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The SPI1 function was associated with the wrong pins: The functions that
those pins provide is either an SPI debug or passthrough function
coupled to SPI1. Make the SPI1 mux function configure the relevant pins
and associate new SPI1DEBUG and SPI1PASSTHRU functions with the pins
that were already defined.
The notation used in the datasheet's multi-function pin table for the SoC is
often creative: in this case the SYS* signals are enabled by a single bit,
which is nothing unusual on its own, but in this case the bit was also
participating in a multi-bit bitfield and therefore represented multiple
functions. This fact was overlooked in the original patch.
Fixes: 56e57cb6c0 (pinctrl: Add pinctrl-aspeed-g5 driver)
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This prevented C20 from successfully being muxed as GPIO.
Fixes: 56e57cb6c0 (pinctrl: Add pinctrl-aspeed-g5 driver)
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Fixes simple typos in the initial commit. There is no behavioural
change.
Fixes: 56e57cb6c0 (pinctrl: Add pinctrl-aspeed-g5 driver)
Reported-by: Xo Wang <xow@google.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Consider a scenario with one pin P that has two signals A and B, where A
is defined to be higher priority than B: That is, if the mux IP is in a
state that would consider both A and B to be active on P, then A will be
the active signal.
To instead configure B as the active signal we must configure the mux so
that A is inactive. The mux state for signals can be described by
logical operations on one or more bits from one or more registers (a
"signal expression"), which in some cases leads to aliased mux states for
a particular signal. Further, signals described by multi-bit bitfields
often do not only need to record the states that would make them active
(the "enable" expressions), but also the states that makes them inactive
(the "disable" expressions). All of this combined leads to four possible
states for a signal:
1. A signal is active with respect to an "enable" expression
2. A signal is not active with respect to an "enable" expression
3. A signal is inactive with respect to a "disable" expression
4. A signal is not inactive with respect to a "disable" expression
In the case of P, if we are looking to activate B without explicitly
having configured A it's enough to consider A inactive if all of A's
"enable" signal expressions evaluate to "not active". If any evaluate to
"active" then the corresponding "disable" states must be applied so it
becomes inactive.
For example, on the AST2400 the pins composing GPIO bank H provide
signals ROMD8 through ROMD15 (high priority) and those for UART6 (low
priority). The mux states for ROMD8 through ROMD15 are aliased, i.e.
there are two mux states that result in the respective signals being
configured:
A. SCU90[6]=1
B. Strap[4,1:0]=100
Further, the second mux state is a 3-bit bitfield that explicitly
defines the enabled state but the disabled state is implicit, i.e. if
Strap[4,1:0] is not exactly "100" then ROMD8 through ROMD15 are not
considered active. This requires the mux function evaluation logic to
use approach 2. above, however the existing code was using approach 3.
The problem was brought to light on the Palmetto machines where the
strap register value is 0x120ce416, and prevented GPIO requests in bank
H from succeeding despite the hardware being in a position to allow
them.
Fixes: 318398c09a8d ("pinctrl: Add core pinctrl support for Aspeed SoCs")
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
I overlooked a few code-paths that can lead to
locks_delete_global_locks().
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Bruce Fields <bfields@fieldses.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-fsdevel@vger.kernel.org
Cc: syzkaller <syzkaller@googlegroups.com>
Link: http://lkml.kernel.org/r/20161008081228.GF3142@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
