The code is correct, but only for a rather subtle reason. This
confused me for quite a while when I read switch_mm, so clarify the
code to avoid confusing other people, too.
TBH, I wouldn't be surprised if this code was only correct by
accident.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/0db86397f968996fb772c443c251415b0b430ddd.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Context switches and TLB flushes can change individual bits of CR4.
CR4 reads take several cycles, so store a shadow copy of CR4 in a
per-cpu variable.
To avoid wasting a cache line, I added the CR4 shadow to
cpu_tlbstate, which is already touched in switch_mm. The heaviest
users of the cr4 shadow will be switch_mm and __switch_to_xtra, and
__switch_to_xtra is called shortly after switch_mm during context
switch, so the cacheline is likely to be hot.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/3a54dd3353fffbf84804398e00dfdc5b7c1afd7d.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CR4 manipulation was split, seemingly at random, between direct
(write_cr4) and using a helper (set/clear_in_cr4). Unfortunately,
the set_in_cr4 and clear_in_cr4 helpers also poke at the boot code,
which only a small subset of users actually wanted.
This patch replaces all cr4 access in functions that don't leave cr4
exactly the way they found it with new helpers cr4_set_bits,
cr4_clear_bits, and cr4_set_bits_and_update_boot.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/495a10bdc9e67016b8fd3945700d46cfd5c12c2f.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently the adjusments made as part of perf_event_task_tick() use the
percpu rotation lists to iterate over any active PMU contexts, but these
are not used by the context rotation code, having been replaced by
separate (per-context) hrtimer callbacks. However, some manipulation of
the rotation lists (i.e. removal of contexts) has remained in
perf_rotate_context(). This leads to the following issues:
* Contexts are not always removed from the rotation lists. Removal of
PMUs which have been placed in rotation lists, but have not been
removed by a hrtimer callback can result in corruption of the rotation
lists (when memory backing the context is freed).
This has been observed to result in hangs when PMU drivers built as
modules are inserted and removed around the creation of events for
said PMUs.
* Contexts which do not require rotation may be removed from the
rotation lists as a result of a hrtimer, and will not be considered by
the unthrottling code in perf_event_task_tick.
This patch fixes the issue by updating the rotation ist when events are
scheduled in/out, ensuring that each rotation list stays in sync with
the HW state. As each event holds a refcount on the module of its PMU,
this ensures that when a PMU module is unloaded none of its CPU contexts
can be in a rotation list. By maintaining a list of perf_event_contexts
rather than perf_event_cpu_contexts, we don't need separate paths to
handle the cpu and task contexts, which also makes the code a little
simpler.
As the rotation_list variables are not used for rotation, these are
renamed to active_ctx_list, which better matches their current function.
perf_pmu_rotate_{start,stop} are renamed to
perf_pmu_ctx_{activate,deactivate}.
Reported-by: Johannes Jensen <johannes.jensen@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Will Deacon <Will.Deacon@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150129134511.GR17721@leverpostej
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When initialising an event, perf_init_event will call try_module_get() to
ensure that the PMU's module cannot be removed for the lifetime of the
event, with __free_event() dropping the reference when the event is
finally destroyed. If something fails after the event has been
initialised, but before the event is installed, perf_event_alloc will
drop the reference on the module.
However, if we fail to initialise an event for some reason (e.g. we ask
an uncore PMU to perform sampling, and it refuses to initialise the
event), we do not drop the refcount. If we try to open such a bogus
event without a precise IDR type, we will loop over each PMU in the pmus
list, incrementing each of their refcounts without decrementing them.
This patch adds a module_put when pmu->event_init(event) fails, ensuring
that the refcounts are balanced in failure cases. As the innards of the
precise and search based initialisation look very similar, this logic is
hoisted out into a new helper function. While the early return for the
failed try_module_get is removed from the search case, this is handled
by the remaining return when ret is not -ENOENT.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1420642611-22667-1-git-send-email-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently we flag available data (via poll syscall) on perf fd with
POLL_IN macro, which is normally used for SIGIO interface.
We've been lucky, because POLLIN (0x1) is subset of POLL_IN (0x20001)
and sys_poll (do_pollfd function) cut the extra bit out (0x20000).
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1422467678-22341-1-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
So what I suspect; but I'm in zombie mode today it seems; is that while
I initially thought that it was impossible for ctx to change when
refcount dropped to 0, I now suspect its possible.
Note that until perf_remove_from_context() the event is still active and
visible on the lists. So a concurrent sys_perf_event_open() from another
task into this task can race.
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stephane Eranian <eranian@gmail.com>
Cc: mark.rutland@arm.com
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150129134434.GB26304@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Jiri reported triggering the new WARN_ON_ONCE in event_sched_out over
the weekend:
event_sched_out.isra.79+0x2b9/0x2d0
group_sched_out+0x69/0xc0
ctx_sched_out+0x106/0x130
task_ctx_sched_out+0x37/0x70
__perf_install_in_context+0x70/0x1a0
remote_function+0x48/0x60
generic_exec_single+0x15b/0x1d0
smp_call_function_single+0x67/0xa0
task_function_call+0x53/0x80
perf_install_in_context+0x8b/0x110
I think the below should cure this; if we install a group leader it
will iterate the (still intact) group list and find its siblings and
try and install those too -- even though those still have the old
event->ctx -- in the new ctx.
Upon installing the first group sibling we'd try and schedule out the
group and trigger the above warn.
Fix this by installing the group leader last, installing siblings
would have no effect, they're not reachable through the group lists
and therefore we don't schedule them.
Also delay resetting the state until we're absolutely sure the events
are quiescent.
Reported-by: Jiri Olsa <jolsa@redhat.com>
Reported-by: vincent.weaver@maine.edu
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150126162639.GA21418@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There have been a few reported issues wrt. the lack of locking around
changing event->ctx. This patch tries to address those.
It avoids the whole rwsem thing; and while it appears to work, please
give it some thought in review.
What I did fail at is sensible runtime checks on the use of
event->ctx, the RCU use makes it very hard.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150123125834.209535886@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add a few WARN()s to catch things that should never happen.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150123125834.150481799@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This fixes a bug in the RCU code I added in ist_enter. It also includes
the sysret stuff discussed here:
http://lkml.kernel.org/g/cover.1421453410.git.luto%40amacapital.net
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Merge tag 'pr-20150201-x86-entry' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux into x86/asm
Pull "x86: Entry cleanups and a bugfix for 3.20" from Andy Lutomirski:
" This fixes a bug in the RCU code I added in ist_enter. It also includes
the sysret stuff discussed here:
http://lkml.kernel.org/g/cover.1421453410.git.luto%40amacapital.net "
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'v3.19-rc7' into x86/asm, to refresh the branch before pulling in new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
One more week's worth of fixes. Worth pointing out here are:
- A patch fixing detaching of iommu registrations when a device is removed --
earlier the ops pointer wasn't managed properly
- Another set of Renesas boards get the same GIC setup fixup as others have in
previous -rcs
- Serial port aliases fixups for sunxi. We did the same to tegra but we
caught that in time before the merge window due to more machines being
affected. Here it took longer for anyone to notice.
- A couple more DT tweaks on sunxi
- A follow-up patch for the mvebu coherency disabling in last -rc batch
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Merge tag 'armsoc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Olof Johansson:
"One more week's worth of fixes. Worth pointing out here are:
- A patch fixing detaching of iommu registrations when a device is
removed -- earlier the ops pointer wasn't managed properly
- Another set of Renesas boards get the same GIC setup fixup as
others have in previous -rcs
- Serial port aliases fixups for sunxi. We did the same to tegra but
we caught that in time before the merge window due to more machines
being affected. Here it took longer for anyone to notice.
- A couple more DT tweaks on sunxi
- A follow-up patch for the mvebu coherency disabling in last -rc
batch"
* tag 'armsoc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
arm: dma-mapping: Set DMA IOMMU ops in arm_iommu_attach_device()
ARM: shmobile: r8a7790: Instantiate GIC from C board code in legacy builds
ARM: shmobile: r8a73a4: Instantiate GIC from C board code in legacy builds
ARM: mvebu: don't set the PL310 in I/O coherency mode when I/O coherency is disabled
ARM: sunxi: dt: Fix aliases
ARM: dts: sun4i: Add simplefb node with de_fe0-de_be0-lcd0-hdmi pipeline
ARM: dts: sun6i: ippo-q8h-v5: Fix serial0 alias
ARM: dts: sunxi: Fix usb-phy support for sun4i/sun5i
Pull input layer updates from Dmitry Torokhov:
"Just a few quirks for PS/2 this time"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: elantech - add more Fujtisu notebooks to force crc_enabled
Input: i8042 - add noloop quirk for Medion Akoya E7225 (MD98857)
Input: synaptics - adjust min/max for Lenovo ThinkPad X1 Carbon 2nd
Commit 8eb23b9f35 ("sched: Debug nested sleeps") added code to report
on nested sleep conditions, which we generally want to avoid because the
inner sleeping operation can re-set the thread state to TASK_RUNNING,
but that will then cause the outer sleep loop not actually sleep when it
calls schedule.
However, that's actually valid traditional behavior, with the inner
sleep being some fairly rare case (like taking a sleeping lock that
normally doesn't actually need to sleep).
And the debug code would actually change the state of the task to
TASK_RUNNING internally, which makes that kind of traditional and
working code not work at all, because now the nested sleep doesn't just
sometimes cause the outer one to not block, but will cause it to happen
every time.
In particular, it will cause the cardbus kernel daemon (pccardd) to
basically busy-loop doing scheduling, converting a laptop into a heater,
as reported by Bruno Prémont. But there may be other legacy uses of
that nested sleep model in other drivers that are also likely to never
get converted to the new model.
This fixes both cases:
- don't set TASK_RUNNING when the nested condition happens (note: even
if WARN_ONCE() only _warns_ once, the return value isn't whether the
warning happened, but whether the condition for the warning was true.
So despite the warning only happening once, the "if (WARN_ON(..))"
would trigger for every nested sleep.
- in the cases where we knowingly disable the warning by using
"sched_annotate_sleep()", don't change the task state (that is used
for all core scheduling decisions), instead use '->task_state_change'
that is used for the debugging decision itself.
(Credit for the second part of the fix goes to Oleg Nesterov: "Can't we
avoid this subtle change in behaviour DEBUG_ATOMIC_SLEEP adds?" with the
suggested change to use 'task_state_change' as part of the test)
Reported-and-bisected-by: Bruno Prémont <bonbons@linux-vserver.org>
Tested-by: Rafael J Wysocki <rjw@rjwysocki.net>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Cc: Ilya Dryomov <ilya.dryomov@inktank.com>,
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>,
Cc: Davidlohr Bueso <dave@stgolabs.net>,
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add two more Fujitsu LIFEBOOK models that also ship with the Elantech
touchpad and don't work with crc_disabled to the quirk list.
Signed-off-by: Rainer Koenig <Rainer.Koenig@ts.fujitsu.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
* Instantiate GIC from C board code in legacy builds on r8a7790 and r8a73a4
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Merge tag 'renesas-soc-fixes3-for-v3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas into fixes
Merge "Third Round of Renesas ARM Based SoC Fixes for v3.19" from Simon Horman:
* Instantiate GIC from C board code in legacy builds on r8a7790 and r8a73a4
* tag 'renesas-soc-fixes3-for-v3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
ARM: shmobile: r8a7790: Instantiate GIC from C board code in legacy builds
ARM: shmobile: r8a73a4: Instantiate GIC from C board code in legacy builds
Signed-off-by: Olof Johansson <olof@lixom.net>
We used to optimize rescheduling and audit on syscall exit. Now
that the full slow path is reasonably fast, remove these
optimizations. Syscall exit auditing is now handled exclusively by
syscall_trace_leave.
This adds something like 10ns to the previously optimized paths on
my computer, presumably due mostly to SAVE_REST / RESTORE_REST.
I think that we should eventually replace both the syscall and
non-paranoid interrupt exit slow paths with a pair of C functions
along the lines of the syscall entry hooks.
Link: http://lkml.kernel.org/r/22f2aa4a0361707a5cfb1de9d45260b39965dead.1421453410.git.luto@amacapital.net
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
The x86_64 entry code currently jumps through complex and
inconsistent hoops to try to minimize the impact of syscall exit
work. For a true fast-path syscall, almost nothing needs to be
done, so returning is just a check for exit work and sysret. For a
full slow-path return from a syscall, the C exit hook is invoked if
needed and we join the iret path.
Using iret to return to userspace is very slow, so the entry code
has accumulated various special cases to try to do certain forms of
exit work without invoking iret. This is error-prone, since it
duplicates assembly code paths, and it's dangerous, since sysret
can malfunction in interesting ways if used carelessly. It's
also inefficient, since a lot of useful cases aren't optimized
and therefore force an iret out of a combination of paranoia and
the fact that no one has bothered to write even more asm code
to avoid it.
I would argue that this approach is backwards. Rather than trying
to avoid the iret path, we should instead try to make the iret path
fast. Under a specific set of conditions, iret is unnecessary. In
particular, if RIP==RCX, RFLAGS==R11, RIP is canonical, RF is not
set, and both SS and CS are as expected, then
movq 32(%rsp),%rsp;sysret does the same thing as iret. This set of
conditions is nearly always satisfied on return from syscalls, and
it can even occasionally be satisfied on return from an irq.
Even with the careful checks for sysret applicability, this cuts
nearly 80ns off of the overhead from syscalls with unoptimized exit
work. This includes tracing and context tracking, and any return
that invokes KVM's user return notifier. For example, the cost of
getpid with CONFIG_CONTEXT_TRACKING_FORCE=y drops from ~360ns to
~280ns on my computer.
This may allow the removal and even eventual conversion to C
of a respectable amount of exit asm.
This may require further tweaking to give the full benefit on Xen.
It may be worthwhile to adjust signal delivery and exec to try hit
the sysret path.
This does not optimize returns to 32-bit userspace. Making the same
optimization for CS == __USER32_CS is conceptually straightforward,
but it will require some tedious code to handle the differences
between sysretl and sysexitl.
Link: http://lkml.kernel.org/r/71428f63e681e1b4aa1a781e3ef7c27f027d1103.1421453410.git.luto@amacapital.net
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
context_tracking_user_exit() has no effect if in_interrupt() returns true,
so ist_enter() didn't work. Fix it by calling exception_enter(), and thus
context_tracking_user_exit(), before incrementing the preempt count.
This also adds an assertion that will catch the problem reliably if
CONFIG_PROVE_RCU=y to help prevent the bug from being reintroduced.
Link: http://lkml.kernel.org/r/261ebee6aee55a4724746d0d7024697013c40a08.1422709102.git.luto@amacapital.net
Fixes: 9592747538 x86, traps: Track entry into and exit from IST context
Reported-and-tested-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Pull i2c fixes from Wolfram Sang:
"i2c driver bugfixes (s3c2410, slave-eeprom, sh_mobile), size
regression "bugfix" (i2c slave), documentation bugfix (st).
Also, one documentation update (da9063), so some devicetrees can now
be verified"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: sh_mobile: terminate DMA reads properly
i2c: Only include slave support if selected
i2c: s3c2410: fix ABBA deadlock by keeping clock prepared
i2c: slave-eeprom: fix boundary check when using sysfs
i2c: st: Rename clock reference to something that exists
DT: i2c: Add devices handled by the da9063 MFD driver
Here are two tiny patches, one fixing up the drivers/Kconfig file, and
one adding a MAINTAINERS entry for the UIO git tree.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-3.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
"Here are two tiny patches, one fixing up the drivers/Kconfig file, and
one adding a MAINTAINERS entry for the UIO git tree"
* tag 'char-misc-3.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
drivers/Kconfig: remove duplicate entry for soc
MAINTAINERS: add git url entry for UIO
Here are two tiny staging tree fixes. One for the nvec driver to
resolve a reported problem, and one to add a MAINTAINERS entry for the
Android drivers.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-3.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging tree fixes from Greg KH:
"Here are two tiny staging tree fixes. One for the nvec driver to
resolve a reported problem, and one to add a MAINTAINERS entry for the
Android drivers"
* tag 'staging-3.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
MAINTAINERS: add Android driver entries
staging: nvec: specify a platform-device base id
Here are some small USB fixes and quirk additions for 3.19-rc7.
All have been in linux-next for a while with no reported problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
"Here are some small USB fixes and quirk additions for 3.19-rc7.
All have been in linux-next for a while with no reported problems"
* tag 'usb-3.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: Add OTG PET device to TPL
usb-storage/SCSI: blacklist FUA on JMicron 152d:2566 USB-SATA controller
uas: Add no-report-opcodes quirk for Simpletech devices with id 4971:8017
storage: Revise/fix quirk for 04E6:000F SCM USB-SCSI converter
usb: phy: never defer probe in non-OF case
usb: dwc2: call dwc2_is_controller_alive() under spinlock
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, but also an event groups fix, two PMU driver
fixes and a CPU model variant addition"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Tighten (and fix) the grouping condition
perf/x86/intel: Add model number for Airmont
perf/rapl: Fix crash in rapl_scale()
perf/x86/intel/uncore: Move uncore_box_init() out of driver initialization
perf probe: Fix probing kretprobes
perf symbols: Introduce 'for' method to iterate over the symbols with a given name
perf probe: Do not rely on map__load() filter to find symbols
perf symbols: Introduce method to iterate symbols ordered by name
perf symbols: Return the first entry with a given name in find_by_name method
perf annotate: Fix memory leaks in LOCK handling
perf annotate: Handle ins parsing failures
perf scripting perl: Force to use stdbool
perf evlist: Remove extraneous 'was' on error message
Pull btrfs fix from Chris Mason:
"We have one more fix for btrfs in my for-linus branch - this was a bug
in the new raid5/6 scrubbing support"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: fix raid56 scrub failed in xfstests btrfs/072
Pull quota and UDF fix from Jan Kara:
"A fix for UDF to properly free preallocated blocks and a fix for quota
so that Q_GETQUOTA quotactl reports correct numbers for XFS filesystem
(and similarly Q_XGETQUOTA quotactl works properly for other
filesystems)"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
quota: Switch ->get_dqblk() and ->set_dqblk() to use bytes as space units
udf: Release preallocation on last writeable close
for x86 (bug introduced in 3.19).
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"The ARM changes are largish, but not too scary. And a simple fix for
x86 (bug introduced in 3.19)"
(Paolo sayus these are the "Final" fixes. We'll see).
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: check LAPIC presence when building apic_map
arm/arm64: KVM: Use kernel mapping to perform invalidation on page fault
arm/arm64: KVM: Invalidate data cache on unmap
arm/arm64: KVM: Use set/way op trapping to track the state of the caches
Two small fixes for the Tegra GART IOMMU driver:
* Provide a .map_sg function for iommu_ops
* Do not register Tegra GART driver as a workaround because of
issues with it when used from DRM code
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Merge tag 'iommu-fixes-v3.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU fixes from Joerg Roedel:
"Two small fixes for the Tegra GART IOMMU driver:
- provide a .map_sg function for iommu_ops
- do not register Tegra GART driver as a workaround because of issues
with it when used from DRM code"
* tag 'iommu-fixes-v3.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/tegra: gart: Provide default ->map_sg() callback
iommu/tegra: gart: Do not register with bus
Pull intel and dp mst drm fixes from Dave Airlie:
"Intel had a few more fixes lined up and no point me sitting on them,
along with a DP MST fix from Rob for a race at undock + vt switch"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm: fix fb-helper vs MST dangling connector ptrs (v2)
drm/i915: BDW Fix Halo PCI IDs marked as ULT.
drm/i915: Fix and clean BDW PCH identification
drm/i915: Only fence tiled region of object.
drm/i915: fix inconsistent brightness after resume
drm/i915: Init PPGTT before context enable
User visible:
- Show precise number of samples in at the end of a 'record' session, if
processing build ids, since we will then traverse the whole perf.data file
and see all the PERF_RECORD_SAMPLE records, otherwise stop showing the
previous off-base heuristicly counted number of "samples" (Namhyung Kim).
- Support to read compressed module from build-id cache (Namhyung Kim)
Infrastructure:
- Cache eh/debug frame offset for dwarf unwind (Namhyung Kim)
- Set header version correctly in all cases (Namhyung Kim)
- Set attr.task bit for a tracking event, to be consistent (Namhyung Kim)
perf tools: Use perf_data_file__fd() consistently
perf symbols: Convert lseek + read to pread
- Don't rely on malloc working for sz 0, fixing another problem when
using uClibc (Vineet Gupta)
- Provide stub for missing pthread_attr_setaffinity_np for libcs where this
is not available, such as uClibc (Vineet Gupta)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- Show precise number of samples in at the end of a 'record' session, if
processing build ids, since we will then traverse the whole perf.data file
and see all the PERF_RECORD_SAMPLE records, otherwise stop showing the
previous off-base heuristicly counted number of "samples" (Namhyung Kim).
- Support to read compressed module from build-id cache (Namhyung Kim)
Infrastructure changes:
- Cache eh/debug frame offset for dwarf unwind (Namhyung Kim)
- Set header version correctly in all cases (Namhyung Kim)
- Set attr.task bit for a tracking event, to be consistent (Namhyung Kim)
perf tools: Use perf_data_file__fd() consistently
perf symbols: Convert lseek + read to pread
- Don't rely on malloc working for sz 0, fixing another problem when
using uClibc (Vineet Gupta)
- Provide stub for missing pthread_attr_setaffinity_np for libcs where this
is not available, such as uClibc (Vineet Gupta)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
DMA read requests could miss proper termination, so two more bytes would
have been read via PIO overwriting the end of the buffer with wrong
data. Make DMA stop handling more readable while we are here.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
We forgot to re-check LAPIC after splitting the loop in commit
173beedc16 (KVM: x86: Software disabled APIC should still deliver
NMIs, 2014-11-02).
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Fixes: 173beedc16
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Fixes memory corruption issues on APM platforms and swapping issues on
DMA-coherent systems.
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Merge tag 'kvm-arm-fixes-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master
Second round of fixes for KVM/ARM for 3.19.
Fixes memory corruption issues on APM platforms and swapping issues on
DMA-coherent systems.
misc i915 fixes, mostly all stable material as well.
* tag 'drm-intel-fixes-2015-01-29' of git://anongit.freedesktop.org/drm-intel:
drm/i915: BDW Fix Halo PCI IDs marked as ULT.
drm/i915: Fix and clean BDW PCH identification
drm/i915: Only fence tiled region of object.
drm/i915: fix inconsistent brightness after resume
drm/i915: Init PPGTT before context enable
VT switch back/forth from console to xserver (for example) has potential
to go horribly wrong if a dynamic DP MST connector ends up in the saved
modeset that is restored when switching back to fbcon.
When removing a dynamic connector, don't forget to clean up the saved
state.
v1: original
v2: null out set->fb if no more connectors to avoid making i915 cranky
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1184968
Cc: stable@vger.kernel.org #v3.17+
Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
dm-thin:
- fix DM cache metadata open/lookup error paths to properly use ERR_PTR
and IS_ERR (fixes: 3.19-rc6 "stable" commit 9b1cc9f251)
- fix DM thin-provisioning to disallow userspace from sending messages
to the thin-pool if the pool is in READ_ONLY or FAIL mode since no
metadata changes are not allowed in these modes.
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Merge tag 'dm-3.19-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
"One stable fix for a dm-cache 3.19-rc6 regression and one stable fix
for dm-thin:
- fix DM cache metadata open/lookup error paths to properly use
ERR_PTR and IS_ERR (fixes: 3.19-rc6 "stable" commit 9b1cc9f251)
- fix DM thin-provisioning to disallow userspace from sending
messages to the thin-pool if the pool is in READ_ONLY or FAIL mode
since no metadata changes are allowed in these modes"
* tag 'dm-3.19-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm thin: don't allow messages to be sent to a pool target in READ_ONLY or FAIL mode
dm cache: fix missing ERR_PTR returns and handling
Highlights include:
- Stable fix for a NFSv4.1 Oops on mount
- Stable fix for an O_DIRECT deadlock condition
- Fix an issue with submounted volumes and fake duplicate inode numbers
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Merge tag 'nfs-for-3.19-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
- Stable fix for a NFSv4.1 Oops on mount
- Stable fix for an O_DIRECT deadlock condition
- Fix an issue with submounted volumes and fake duplicate inode
numbers"
* tag 'nfs-for-3.19-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFS: Fix use of nfs_attr_use_mounted_on_fileid()
NFSv4.1: Fix an Oops in nfs41_walk_client_list
nfs: fix dio deadlock when O_DIRECT flag is flipped
Pull Ceph fixes from Sage Weil:
"These paches from Ilya finally squash a race condition with layered
images that he's been chasing for a while"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
rbd: drop parent_ref in rbd_dev_unprobe() unconditionally
rbd: fix rbd_dev_parent_get() when parent_overlap == 0
When handling a fault in stage-2, we need to resync I$ and D$, just
to be sure we don't leave any old cache line behind.
That's very good, except that we do so using the *user* address.
Under heavy load (swapping like crazy), we may end up in a situation
where the page gets mapped in stage-2 while being unmapped from
userspace by another CPU.
At that point, the DC/IC instructions can generate a fault, which
we handle with kvm->mmu_lock held. The box quickly deadlocks, user
is unhappy.
Instead, perform this invalidation through the kernel mapping,
which is guaranteed to be present. The box is much happier, and so
am I.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Let's assume a guest has created an uncached mapping, and written
to that page. Let's also assume that the host uses a cache-coherent
IO subsystem. Let's finally assume that the host is under memory
pressure and starts to swap things out.
Before this "uncached" page is evicted, we need to make sure
we invalidate potential speculated, clean cache lines that are
sitting there, or the IO subsystem is going to swap out the
cached view, loosing the data that has been written directly
into memory.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Trying to emulate the behaviour of set/way cache ops is fairly
pointless, as there are too many ways we can end-up missing stuff.
Also, there is some system caches out there that simply ignore
set/way operations.
So instead of trying to implement them, let's convert it to VA ops,
and use them as a way to re-enable the trapping of VM ops. That way,
we can detect the point when the MMU/caches are turned off, and do
a full VM flush (which is what the guest was trying to do anyway).
This allows a 32bit zImage to boot on the APM thingy, and will
probably help bootloaders in general.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
When dso_cache__read() is called, it reads data from the given offset
using lseek + normal read syscall. It can be combined to a single pread
syscall.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1422518843-25818-40-git-send-email-namhyung@kernel.org
[ Fixed it up when cherry picking it from the multi threaded patchkit ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Do not reference file->fd directly since we want hide the
implementation details from outside for possible future changes.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1422518843-25818-8-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The commit c00c48fc6e ("perf symbols: Preparation for compressed
kernel module support") added support for compressed kernel modules but
it only supports system path DSOs. When a dso is read from build-id
cache, its filename doesn't end with ".gz" but has build-id. In this
case, we should fallback to the original dso->name.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1422518843-25818-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
