The coprocessor register CRn for accesses to the debug register can be a
different one than C0. Take this into account for the ARM_DBG_READ and
the ARM_DBG_WRITE macro.
The inline assembler calls which used a coprocessor register CRn other
than C0 are replaced by the ARM_DBG_READ or ARM_DBG_WRITE macro.
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Rather than attempt to enable monitor mode explicitly when scheduling in
a breakpoint event (which could raise an undefined exception trap when
accessing DBGDSCRext), instead check that DBGDSCRint.MDBGen is set
during event validation and report an error to the caller if not.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Booting on a v6 core without the CPUID feature registers (e.g. 1136)
leads to a noisy dmesg complaining about their absence.
This patch changes the pr_warning into a pr_warn_once to keep the log
quieter.
Signed-off-by: Will Deacon <will.deacon@arm.com>
v6 cores do not provide a way to clear the debug registers without first
enabling monitor mode, meaning that we could take spurious debug
exceptions. Instead, rely on the registers being in a sane state when we
boot as they are defined to be disabled out of reset anyway.
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The debug register reset sequence for v7 and v7.1 is congruent with
tap-dancing through a minefield.
Rather than wait until we've blown ourselves to pieces, this patch
instead checks the debug_err_mask after each potentially faulting
operation. We also move the enabling of monitor_mode to the end of the
sequence in order to prevent spurious debug events generated by UNKNOWN
register values.
Reported-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Detecting whether halting debug is enabled is no longer possible via
the DBGDSCR in v7.1, returning an UNKNOWN value for the HDBGen bit via
CP14 when the OS lock is clear.
This patch removes the halting mode check and ensures that accesses to
the internal and external views of the DBGDSCR are serialised with an
instruction barrier.
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The OS save and restore register are optional in debug architecture v7,
so check the status register before attempting to clear the OS lock.
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Commit 7be2958 (ARM: PMU: Add runtime PM Support) updated the ARM PMU code to
use runtime PM which was prototyped and validated on the OMAP devices. In this
commit, there is no call pm_runtime_enable() and for OMAP devices
pm_runtime_enable() is currently being called from the OMAP PMU code when the
PMU device is created. However, there are two problems with this:
1. For any other ARM device wishing to use runtime PM for PMU they will need
to call pm_runtime_enable() for runtime PM to work.
2. When booting with device-tree and using device-tree to create the PMU
device, pm_runtime_enable() needs to be called from within the ARM PERF
driver as we are no longer calling any device specific code to create the
device. Hence, PMU does not work on OMAP devices that use the runtime PM
callbacks when using device-tree to create the PMU device.
Therefore, call pm_runtime_enable() directly from the ARM PMU driver when
registering the device. For platforms that do not use runtime PM,
pm_runtime_enable() does nothing and for platforms that do use runtime PM but
may not require it specifically for PMU, this will just add a little overhead
when initialising and uninitialising the PMU device.
Tested with PERF on OMAP2420, OMAP3430 and OMAP4460.
Acked-by: Kevin Hilman <khilman@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Perf has three ways to name a PMU: either by passing an explicit char *,
reading arm_pmu->name or accessing arm_pmu->pmu.name.
Just use arm_pmu->name consistently in the ARM backend.
Signed-off-by: Will Deacon <will.deacon@arm.com>
When attempting to reset the PMU state for either a NULL PMU or a PMU
implementation without a reset function, return NOTIFY_DONE from the CPU
notifier as we don't care about the hotplug event.
Signed-off-by: Will Deacon <will.deacon@arm.com>
The current practice of registering the cpu hotplug notifier at PMU
registration time won't be safe with multiple PMUs, as we'll repeatedly
attempt to register the notifier. This has the unfortunate effect of
silently corrupting the notifier list, leading to boot stalling.
Instead, register the notifier at init time. Its sanity checks will
prevent anything bad from happening if the notifier is called before we
have any PMUs registered.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Multi-cluster ARMv7 systems may have CPU PMUs with different number of
counters.
This patch updates armv7_pmnc_counter_valid so that it takes a pmu
argument and checks the counter validity against that. We also remove a
number of redundant counter checks whether the current PMU is not easily
retrievable.
Signed-off-by: Sudeep KarkadaNagesha <Sudeep.KarkadaNagesha@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The arm_pmu functions have wildly varied parameters which can often be
derived from struct perf_event.
This patch changes the arm_pmu function prototypes so that struct
perf_event pointers are passed in preference to fields that can be
derived from the event.
Signed-off-by: Sudeep KarkadaNagesha <Sudeep.KarkadaNagesha@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Supporting multiple, heterogeneous CPU PMUs requires us to allocate the
arm_pmu structures dynamically as the devices are probed.
This patch removes the static structure definitions for each CPU PMU
type and instead passes pointers to the PMU-specific init functions.
Signed-off-by: Sudeep KarkadaNagesha <Sudeep.KarkadaNagesha@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Add minimal guest support to perf, so it can distinguish whether
the PMU interrupt was in the host or the guest, as well as collecting
some very basic information (guest PC, user vs kernel mode).
This is not feature complete though, as it doesn't support backtracing
in the guest.
Based on the x86 implementation, tested with KVM/ARM.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Dmitry Torokhov <dtor@vmware.com>
Cc: stable@vger.kernel.org
Cc: linux-graphics-maintainer@vmware.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
The device would not reset properly when resuming from hibernation.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Dmitry Torokhov <dtor@vmware.com>
Cc: stable@vger.kernel.org
Cc: linux-graphics-maintainer@vmware.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
For non MIPSr2 processors, such as the BMIPS 5000, calls to
arch_local_irq_disable() and others may be preempted, and in doing
so a stale value may be restored to c0_status. This fix disables
preemption for such processors prior to the call and enables it
after the call.
Those functions that needed this fix have been "outlined" to
mips-atomic.c, as they are no longer good candidates for inlining.
This bug was observed in a BMIPS 5000, occuring once every few hours
in a continuous reboot test. It was traced to the write_lock_irq()
function which was being invoked in release_task() in exit.c.
By placing a number of "nops" inbetween the mfc0/mtc0 pair in
arch_local_irq_disable(), which is called by write_lock_irq(), we
were able to greatly increase the occurance of this bug. Similarly,
the application of this commit silenced the bug.
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: Kevin Cernekee cernekee@gmail.com
Cc: Jim Quinlan <jim2101024@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/4321/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The "else clause" of most functions in bitops.h invoked
raw_local_irq_{save,restore}() and in doing so had a dependency on
irqflags.h. This fix moves said code to bitops.c, removing the
dependency.
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: Kevin Cernekee cernekee@gmail.com
Cc: Jim Quinlan <jim2101024@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/4320/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[ralf@linux-mips.org: No functional change but it's consistent with how
use types elsewhere in the code.]
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: Kevin Cernekee cernekee@gmail.com
Cc: Jim Quinlan <jim2101024@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/4319/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
So far is_compat_task() was testing for 32-bit registers if O32 support
was enabled and if O32 support was disabled but N32 enabled it was testing
for 32-bit address space. So if both O32 and N32 were enabled a N32
task was not considered a compat task, whops.
This still leaves potential cases where O32 and N32 need different treatment
unsolved. But that's another commit.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This config item has not carried much meaning for a while now and is
almost always enabled by default. As agreed during the Linux kernel
summit, remove it.
CC: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
All the headers but kvm_para.h use the Kbuild infrastructure to
get to the asm-generic headers.
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
For kernel/bound.c being compiled by native compiler, it will generate following errors in gcc 4.4.3:
CC kernel/bounds.s
In file included from include/linux/bug.h:4,
from include/linux/page-flags.h:9,
from kernel/bounds.c:9:
arch/unicore32/include/asm/bug.h:22: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'void'
arch/unicore32/include/asm/bug.h:23: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'void'
So, we moved definitions in asm/bug.h to arch/unicore32/kernel/setup.h to solve the problem.
Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
When disintegrate system.h, I left an error in asm/cmpxchg.h, which
will result in following error:
arch/unicore32/include/asm/cmpxchg.h: In function '__xchg':
arch/unicore32/include/asm/cmpxchg.h:38: error: void value not ignored as it ought to be
Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Because our PCI-bus handler confines dma zone into 128M, we should add
CONFIG_ZONE_DMA for all boards. Otherwise, all memory bigger than 128M
will be pushed into ZONE_MOVABLE.
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Liu Guoli <liuguoli@mprc.pku.edu.cn>
Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Commit d065bd810b
(mm: retry page fault when blocking on disk transfer) and
commit 37b23e0525
(x86,mm: make pagefault killable)
The above commits introduced changes into the x86 pagefault handler
for making the page fault handler retryable as well as killable.
These changes reduce the mmap_sem hold time, which is crucial
during OOM killer invocation.
Port these changes to unicore32.
Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
If the cipher suites need to be allocated, but this
allocation fails, this leaks the internal scan request.
Fix that by going to the correct error handling label.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
- A set of SPEAr pinctrl fixes that recently arrived
- A fixup for the Samsung/Exynos Kconfig deps
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Merge tag 'pinctrl-for-v3.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pinctrl fixes from Linus Walleij:
- A set of SPEAr pinctrl fixes that recently arrived
- A fixup for the Samsung/Exynos Kconfig deps
* tag 'pinctrl-for-v3.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: samsung and exynos need to depend on OF && GPIOLIB
pinctrl: SPEAr1340: Add clcd sleep mode pin configuration
pinctrl: SPEAr1340: Make DDR reset & clock pads as gpio
pinctrl: SPEAr1310: add register entries for enabling pad direction
pinctrl: SPEAr1310: Separate out pci pins from pcie_sata pin group
pinctrl: SPEAr1310: Fix value of PERIP_CFG reigster and MCIF_SEL_SHIFT
pinctrl: SPEAr1310: fix clcd high resolution pin group name
pinctrl: SPEAr320: Correct pad mux entries for rmii/smii
pinctrl: SPEAr3xx: correct register space to configure pwm
pinctrl: SPEAr: Don't update all non muxreg bits on pinctrl_disable
Pull s390 fixes from Martin Schwidefsky:
"A couple of bug fixes. I keep the fingers crossed that we now got
transparent huge pages ready for prime time."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/cio: fix length calculation in idset.c
s390/sclp: fix addressing mode clobber
s390: Move css limits from drivers/s390/cio/ to include/asm/.
s390/thp: respect page protection in pmd_none() and pmd_present()
s390/mm: use pmd_large() instead of pmd_huge()
s390/cio: suppress 2nd path verification during resume
Pull HID fix from Jiri Kosina:
"This reverts a patch that causes regression in binding between HID
devices and drivers during device unplug/replug cycle."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
HID: hidraw: put old deallocation mechanism in place
Merge misc fixes from Andrew Morton:
"Five fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (5 patches)
h8300: add missing L1_CACHE_SHIFT
mm: bugfix: set current->reclaim_state to NULL while returning from kswapd()
fanotify: fix missing break
revert "epoll: support for disabling items, and a self-test app"
checkpatch: improve network block comment style checking
Pull drm fixes from Dave Airlie:
"Just radeon and nouveau, mostly regressions fixers, and a couple of
radeon register checker fixes."
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/nouveau: fix acpi edid retrieval
drm/nvc0/disp: fix regression in vblank semaphore release
drm/nv40/mpeg: fix context handling
drm/nv40/graph: fix typo in type names
drm/nv41/vm: fix typo in type name
drm/radeon/si: add some missing regs to the VM reg checker
drm/radeon/cayman: add some missing regs to the VM reg checker
drm/radeon/dce3: switch back to old pll allocation order for discrete
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull virtio and module fixes from Rusty Russell:
"YA module signing build tweak, and two cc'd to stable."
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
virtio: Don't access index after unregister.
modules: don't break modules_install on external modules with no key.
module: fix out-by-one error in kallsyms
- fix for large transactions spanning multiple iclog buffers
- zero the allocation_args structure on the stack before using it
to determine whether to use a worker for allocation
- move allocation stack switch to xfs_bmapi_allocate in order
to prevent deadlock on AGF buffers
- growfs no longer reads in garbage for new secondary superblocks
- silence a build warning
- ensure that invalid buffers never get written to disk while on
free list
- don't vmap inode cluster buffers during free
- fix buffer shutdown reference count mismatch
- fix reading of wrapped log data
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Merge tag 'for-linus-v3.7-rc5' of git://oss.sgi.com/xfs/xfs
Pull xfs bugfixes from Ben Myers:
- fix for large transactions spanning multiple iclog buffers
- zero the allocation_args structure on the stack before using it to
determine whether to use a worker for allocation
- move allocation stack switch to xfs_bmapi_allocate in order to
prevent deadlock on AGF buffers
- growfs no longer reads in garbage for new secondary superblocks
- silence a build warning
- ensure that invalid buffers never get written to disk while on free
list
- don't vmap inode cluster buffers during free
- fix buffer shutdown reference count mismatch
- fix reading of wrapped log data
* tag 'for-linus-v3.7-rc5' of git://oss.sgi.com/xfs/xfs:
xfs: fix reading of wrapped log data
xfs: fix buffer shudown reference count mismatch
xfs: don't vmap inode cluster buffers during free
xfs: invalidate allocbt blocks moved to the free list
xfs: silence uninitialised f.file warning.
xfs: growfs: don't read garbage for new secondary superblocks
xfs: move allocation stack switch up to xfs_bmapi_allocate
xfs: introduce XFS_BMAPI_STACK_SWITCH
xfs: zero allocation_args on the kernel stack
xfs: only update the last_sync_lsn when a transaction completes
Fix the build error
lib/atomic64.c: In function 'lock_addr':
lib/atomic64.c:40:11: error: 'L1_CACHE_SHIFT' undeclared (first use in this function)
lib/atomic64.c:40:11: note: each undeclared identifier is reported only once for each function it appears in
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In kswapd(), set current->reclaim_state to NULL before returning, as
current->reclaim_state holds reference to variable on kswapd()'s stack.
In rare cases, while returning from kswapd() during memory offlining,
__free_slab() and freepages() can access the dangling pointer of
current->reclaim_state.
Signed-off-by: Takamori Yamaguchi <takamori.yamaguchi@jp.sony.com>
Signed-off-by: Aaditya Kumar <aaditya.kumar@ap.sony.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Anders Blomdell noted in 2010 that Fanotify lost events and provided a
test case. Eric Paris confirmed it was a bug and posted a fix to the
list
https://groups.google.com/forum/?fromgroups=#!topic/linux.kernel/RrJfTfyW2BE
but never applied it. Repeated attempts over time to actually get him
to apply it have never had a reply from anyone who has raised it
So apply it anyway
Signed-off-by: Alan Cox <alan@linux.intel.com>
Reported-by: Anders Blomdell <anders.blomdell@control.lth.se>
Cc: Eric Paris <eparis@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert commit 03a7beb55b ("epoll: support for disabling items, and a
self-test app") pending resolution of the issues identified by Michael
Kerrisk, copied below.
We'll revisit this for 3.8.
: I've taken a look at this patch as it currently stands in 3.7-rc1, and
: done a bit of testing. (By the way, the test program
: tools/testing/selftests/epoll/test_epoll.c does not compile...)
:
: There are one or two places where the behavior seems a little strange,
: so I have a question or two at the end of this mail. But other than
: that, I want to check my understanding so that the interface can be
: correctly documented.
:
: Just to go though my understanding, the problem is the following
: scenario in a multithreaded application:
:
: 1. Multiple threads are performing epoll_wait() operations,
: and maintaining a user-space cache that contains information
: corresponding to each file descriptor being monitored by
: epoll_wait().
:
: 2. At some point, a thread wants to delete (EPOLL_CTL_DEL)
: a file descriptor from the epoll interest list, and
: delete the corresponding record from the user-space cache.
:
: 3. The problem with (2) is that some other thread may have
: previously done an epoll_wait() that retrieved information
: about the fd in question, and may be in the middle of using
: information in the cache that relates to that fd. Thus,
: there is a potential race.
:
: 4. The race can't solved purely in user space, because doing
: so would require applying a mutex across the epoll_wait()
: call, which would of course blow thread concurrency.
:
: Right?
:
: Your solution is the EPOLL_CTL_DISABLE operation. I want to
: confirm my understanding about how to use this flag, since
: the description that has accompanied the patches so far
: has been a bit sparse
:
: 0. In the scenario you're concerned about, deleting a file
: descriptor means (safely) doing the following:
: (a) Deleting the file descriptor from the epoll interest list
: using EPOLL_CTL_DEL
: (b) Deleting the corresponding record in the user-space cache
:
: 1. It's only meaningful to use this EPOLL_CTL_DISABLE in
: conjunction with EPOLLONESHOT.
:
: 2. Using EPOLL_CTL_DISABLE without using EPOLLONESHOT in
: conjunction is a logical error.
:
: 3. The correct way to code multithreaded applications using
: EPOLL_CTL_DISABLE and EPOLLONESHOT is as follows:
:
: a. All EPOLL_CTL_ADD and EPOLL_CTL_MOD operations should
: should EPOLLONESHOT.
:
: b. When a thread wants to delete a file descriptor, it
: should do the following:
:
: [1] Call epoll_ctl(EPOLL_CTL_DISABLE)
: [2] If the return status from epoll_ctl(EPOLL_CTL_DISABLE)
: was zero, then the file descriptor can be safely
: deleted by the thread that made this call.
: [3] If the epoll_ctl(EPOLL_CTL_DISABLE) fails with EBUSY,
: then the descriptor is in use. In this case, the calling
: thread should set a flag in the user-space cache to
: indicate that the thread that is using the descriptor
: should perform the deletion operation.
:
: Is all of the above correct?
:
: The implementation depends on checking on whether
: (events & ~EP_PRIVATE_BITS) == 0
: This replies on the fact that EPOLL_CTL_AD and EPOLL_CTL_MOD always
: set EPOLLHUP and EPOLLERR in the 'events' mask, and EPOLLONESHOT
: causes those flags (as well as all others in ~EP_PRIVATE_BITS) to be
: cleared.
:
: A corollary to the previous paragraph is that using EPOLL_CTL_DISABLE
: is only useful in conjunction with EPOLLONESHOT. However, as things
: stand, one can use EPOLL_CTL_DISABLE on a file descriptor that does
: not have EPOLLONESHOT set in 'events' This results in the following
: (slightly surprising) behavior:
:
: (a) The first call to epoll_ctl(EPOLL_CTL_DISABLE) returns 0
: (the indicator that the file descriptor can be safely deleted).
: (b) The next call to epoll_ctl(EPOLL_CTL_DISABLE) fails with EBUSY.
:
: This doesn't seem particularly useful, and in fact is probably an
: indication that the user made a logic error: they should only be using
: epoll_ctl(EPOLL_CTL_DISABLE) on a file descriptor for which
: EPOLLONESHOT was set in 'events'. If that is correct, then would it
: not make sense to return an error to user space for this case?
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: "Paton J. Lewis" <palewis@adobe.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some comment styles in net and drivers/net are flagged inappropriately.
Avoid proclaiming inline comments like:
int a = b; /* some comment */
and block comments like:
/*********************
* some comment
********************/
are defective.
Tested with
$ cat drivers/net/t.c
/* foo */
/*
* foo
*/
/* foo
*/
/* foo
* bar */
/****************************
* some long block comment
***************************/
struct foo {
int bar; /* another test */
};
$
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: David Miller <davem@davemloft.net>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
just some misc regression fixes and typo fixes.
* 'drm-nouveau-fixes' of git://anongit.freedesktop.org/git/nouveau/linux-2.6:
drm/nouveau: fix acpi edid retrieval
drm/nvc0/disp: fix regression in vblank semaphore release
drm/nv40/mpeg: fix context handling
drm/nv40/graph: fix typo in type names
drm/nv41/vm: fix typo in type name
Virtio wants to release used indices after the corresponding
virtio device has been unregistered. However, virtio does not
hold an extra reference, giving up its last reference with
device_unregister(), making accessing dev->index afterwards
invalid.
I actually saw problems when testing my (not-yet-merged)
virtio-ccw code:
- device_add virtio-net,id=xxx
-> creates device virtio<n> with n>0
- device_del xxx
-> deletes virtio<n>, but calls ida_simple_remove with an
index of 0
- device_add virtio-net,id=xxx
-> tries to add virtio0, which is still in use...
So let's save the index we want to release before calling
device_unregister().
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Cc: stable@kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Commit c0077061e7 accidentally inverted the logic for nouveau_acpi_edid,
causing it to only show a connector as connected when the edid could not
be retrieved with acpi.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
