The current documentation is incomplete wrt the intel_pstate legacy
internal governors. The confusion comes from the general cpufreq
governors which also use the names performance and powersave. This patch
better differentiates between the two sets of governors and gives an
explanation of how the internal P-state governors behave differently from
one another.
Also fix two minor typos.
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Kristen Carlson Accardi <kristen@linux.intel.com>
Cc: Dirk Brandewie <dirk.j.brandewie@intel.com>
Cc: x86@kernel.org
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Current documentation over use case for EXPORT_SYMBOL_GPL()
only acknowledges functions which are "an internal implementation
issue, and not really an interface". In practice these days
though we have some maintainers taking on preferences to require
all new functionality go in with EXPORT_SYMBOL_GPL().
A maintainer asking developers to use EXPORT_SYMBOL_GPL()
for new functionality tends to be a well accepted and understood
position that maintainers can take and typically requires the
maintainers educating contributing developers on their own
positions and requirements.
Developers who submit code to maintainers not familiar with
these preferences as optional for new functionality need explicit
guidence though as existing documentation does not acknowledge
this as a valid possibility. Without this being documented some
maintainers are reluctant to accept new functionality with
EXPORT_SYMBOL_GPL().
This extends the use case documentation for EXPORT_SYMBOL_GPL()
to acknowledge acceptance for new functionality.
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
[jc: wording tweaked with permission]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
In the functions compat_get_bitmap() and compat_put_bitmap() the
variable nr_compat_longs stores how many compat_ulong_t words should be
copied in a loop.
The copy loop itself is this:
if (nr_compat_longs-- > 0) {
if (__get_user(um, umask)) return -EFAULT;
} else {
um = 0;
}
Since nr_compat_longs gets unconditionally decremented in each loop and
since it's type is unsigned this could theoretically lead to out of
bounds accesses to userspace if nr_compat_longs wraps around to
(unsigned)(-1).
Although the callers currently do not trigger out-of-bounds accesses, we
should better implement the loop in a safe way to completely avoid such
warp-arounds.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Added the USB serial device ID for the HubZ dual ZigBee
and Z-Wave radio dongle.
Signed-off-by: John D. Blair <johnb@candicontrols.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Pull dmaengine fixes from Vinod Koul:
"We have two small fixes:
- pl330 termination hang fix by Krzysztof
- hsu memory leak fix by Peter"
* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: hsu: Fix memory leak when stopping a running transfer
dmaengine: pl330: Fix hang on dmaengine_terminate_all on certain boards
Commit 066450be41 ("perf/x86/intel/pt: Clean up the control flow
in pt_pmu_hw_init()") changed attribute initialization so that
only the first attribute gets initialized using
sysfs_attr_init(), which upsets lockdep.
This patch fixes the glitch so that all allocated attributes are
properly initialized thus fixing the lockdep warning reported by
Tvrtko and Imre.
Reported-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reported-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: <linux-kernel@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
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>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
commit 65ca7514e2
Author: Damien Lespiau <damien.lespiau@intel.com>
Date: Mon Feb 9 19:33:22 2015 +0000
drm/i915/skl: Implement WaBarrierPerformanceFixDisable
got misapplied and the code landed in chv_init_workarounds() instead of
the intended skl_init_workarounds(). Move it over to the right place.
Cc: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Add all missing platforms handled by intel_set_memory_cxsr() to the
i915_sr_status debugfs entry.
v2: Add G4X too. (Ville)
Clarify the change also affects CHV. (Ander)
References: https://bugs.freedesktop.org/show_bug.cgi?id=89792
Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
After GPU reset, HW is losing the address of HWS page in the register.
The page itself is valid except that HW is not aware of its location.
[ 64.368623] [drm:gen8_init_common_ring [i915]] *ERROR* HWS Page address = 0x00000000
[ 64.368655] [drm:gen8_init_common_ring [i915]] *ERROR* HWS Page address = 0x00000000
[ 64.368681] [drm:gen8_init_common_ring [i915]] *ERROR* HWS Page address = 0x00000000
[ 64.368704] [drm:gen8_init_common_ring [i915]] *ERROR* HWS Page address = 0x00000000
This patch reloads this value into the register during ring init.
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
One minor fix for last -rc of 4.1. The fix moves the update of an attribute in
topology to *after* it is actually initialized.
* tag 'drm-amdkfd-fixes-2015-06-03' of git://people.freedesktop.org/~gabbayo/linux:
drm/amdkfd: fix topology bug with capability attr.
One more small r7xx audio regression fix for 4.1
* 'drm-fixes-4.1' of git://people.freedesktop.org/~agd5f/linux:
drm/radeon: use proper ACR regisiter for DCE3.2
Pull block layer fixes from Jens Axboe:
"Sending this off now, as I'm not aware of other current bugs, nor do I
expect further fixes before 4.1 final. This contains two fixes:
- a fix for a bdi unregister warning that gets spewed on md, due to a
regression introduced earlier in this cycle. From Neil Brown.
- a fix for a compile warning for NVMe on 32-bit platforms, also a
regression introduced in this cycle. From Arnd Bergmann"
* 'for-linus' of git://git.kernel.dk/linux-block:
NVMe: fix type warning on 32-bit
block: discard bdi_unregister() in favour of bdi_destroy()
OSDL has been gone for many years, looks like there still was
one reference to it.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch fixes a bug where the number of watch points
was shown before it was actually calculated
Signed-off-by: Alexey Skidanov <Alexey.Skidanov@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
strnlen_user() can return a number in a range 0 to count +
sizeof(unsigned long) - 1. Clarify the comment at the top of the
function so that users don't think the function returns at most count+1.
Signed-off-by: Jan Kara <jack@suse.cz>
[ Also added commentary about preferably not using this function ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The previous patches added arch support matrices for more than 40 generic kernel features
that need per architecture support.
The structure of the feature descriptions is the following:
Each feature has its own directory under Documentation/features/subsystem_name/feature_name/,
and the arch-support.txt file shows its current arch porting status.
For example, lockdep support is shown the following way:
triton:~/tip> cat Documentation/features/locking/lockdep/arch-support.txt
#
# Feature name: lockdep
# Kconfig: LOCKDEP_SUPPORT
# description: arch supports the runtime locking correctness debug facility
#
-----------------------
| arch |status|
-----------------------
| alpha: | TODO |
| arc: | ok |
| arm: | ok |
| arm64: | ok |
| avr32: | ok |
| blackfin: | ok |
| c6x: | TODO |
| cris: | TODO |
| frv: | TODO |
| h8300: | TODO |
| hexagon: | ok |
| ia64: | TODO |
| m32r: | TODO |
| m68k: | TODO |
| metag: | ok |
| microblaze: | ok |
| mips: | ok |
| mn10300: | TODO |
| nios2: | TODO |
| openrisc: | TODO |
| parisc: | TODO |
| powerpc: | ok |
| s390: | ok |
| score: | ok |
| sh: | ok |
| sparc: | ok |
| tile: | ok |
| um: | ok |
| unicore32: | ok |
| x86: | ok |
| xtensa: | ok |
-----------------------
For generic kernel features that need architecture support, the
arch-support.txt file in each feature directory shows the arch
support matrix, for all upstream Linux architectures.
The meaning of entries in the tables is:
| ok | # feature supported by the architecture
|TODO| # feature not yet supported by the architecture
| .. | # feature cannot be supported by the hardware
This directory structure can be used in the future to add other
files - such as porting guides, testing description, etc.
The Documentation/features/ hierarchy may also include generic
kernel features that works on every architecture, in that case
the arch-support.txt file will list every architecture as
supported.
To list an architecture's unsupported features, just do something
like:
triton:~/tip> git grep -lE 'x86.*TODO' Documentation/features/*/*/arch-support.txt
Documentation/features/lib/strncasecmp/arch-support.txt
Documentation/features/time/arch-tick-broadcast/arch-support.txt
which will print the list of not yet supported features.
The Documentation/features/list-arch.sh script will print the current
support matrix of one architecture:
triton:~/tip> Documentation/features/list-arch.sh
#
# Kernel feature support matrix of the 'x86' architecture:
#
core/ BPF-JIT : ok | HAVE_BPF_JIT # arch supports BPF JIT optimizations
core/ generic-idle-thread : ok | GENERIC_SMP_IDLE_THREAD # arch makes use of the generic SMP idle thread facility
core/ jump-labels : ok | HAVE_ARCH_JUMP_LABEL # arch supports live patched, high efficiency branches
core/ tracehook : ok | HAVE_ARCH_TRACEHOOK # arch supports tracehook (ptrace) register handling APIs
debug/ gcov-profile-all : ok | ARCH_HAS_GCOV_PROFILE_ALL # arch supports whole-kernel GCOV code coverage profiling
debug/ KASAN : ok | HAVE_ARCH_KASAN # arch supports the KASAN runtime memory checker
debug/ kgdb : ok | HAVE_ARCH_KGDB # arch supports the kGDB kernel debugger
debug/ kprobes : ok | HAVE_KPROBES # arch supports live patched kernel probe
debug/ kprobes-on-ftrace : ok | HAVE_KPROBES_ON_FTRACE # arch supports combined kprobes and ftrace live patching
debug/ kretprobes : ok | HAVE_KRETPROBES # arch supports kernel function-return probes
debug/ optprobes : ok | HAVE_OPTPROBES # arch supports live patched optprobes
debug/ stackprotector : ok | HAVE_CC_STACKPROTECTOR # arch supports compiler driven stack overflow protection
debug/ uprobes : ok | ARCH_SUPPORTS_UPROBES # arch supports live patched user probes
debug/ user-ret-profiler : ok | HAVE_USER_RETURN_NOTIFIER # arch supports user-space return from system call profiler
io/ dma-api-debug : ok | HAVE_DMA_API_DEBUG # arch supports DMA debug facilities
io/ dma-contiguous : ok | HAVE_DMA_CONTIGUOUS # arch supports the DMA CMA (continuous memory allocator)
io/ dma_map_attrs : ok | HAVE_DMA_ATTRS # arch provides dma_*map*_attrs() APIs
io/ sg-chain : ok | ARCH_HAS_SG_CHAIN # arch supports chained scatter-gather lists
lib/ strncasecmp : TODO | __HAVE_ARCH_STRNCASECMP # arch provides an optimized strncasecmp() function
locking/ cmpxchg-local : ok | HAVE_CMPXCHG_LOCAL # arch supports the this_cpu_cmpxchg() API
locking/ lockdep : ok | LOCKDEP_SUPPORT # arch supports the runtime locking correctness debug facility
locking/ queued-rwlocks : ok | ARCH_USE_QUEUED_RWLOCKS # arch supports queued rwlocks
locking/ queued-spinlocks : ok | ARCH_USE_QUEUED_SPINLOCKS # arch supports queued spinlocks
locking/ rwsem-optimized : ok | Optimized asm/rwsem.h # arch provides optimized rwsem APIs
perf/ kprobes-event : ok | HAVE_REGS_AND_STACK_ACCESS_API # arch supports kprobes with perf events
perf/ perf-regs : ok | HAVE_PERF_REGS # arch supports perf events register access
perf/ perf-stackdump : ok | HAVE_PERF_USER_STACK_DUMP # arch supports perf events stack dumps
sched/ numa-balancing : ok | ARCH_SUPPORTS_NUMA_BALANCING # arch supports NUMA balancing
seccomp/ seccomp-filter : ok | HAVE_ARCH_SECCOMP_FILTER # arch supports seccomp filters
time/ arch-tick-broadcast : TODO | ARCH_HAS_TICK_BROADCAST # arch provides tick_broadcast()
time/ clockevents : ok | GENERIC_CLOCKEVENTS # arch support generic clock events
time/ context-tracking : ok | HAVE_CONTEXT_TRACKING # arch supports context tracking for NO_HZ_FULL
time/ irq-time-acct : ok | HAVE_IRQ_TIME_ACCOUNTING # arch supports precise IRQ time accounting
time/ modern-timekeeping : ok | !ARCH_USES_GETTIMEOFFSET # arch does not use arch_gettimeoffset() anymore
time/ virt-cpuacct : ok | HAVE_VIRT_CPU_ACCOUNTING # arch supports precise virtual CPU time accounting
vm/ ELF-ASLR : ok | ARCH_HAS_ELF_RANDOMIZE # arch randomizes the stack, heap and binary images of ELF binaries
vm/ huge-vmap : ok | HAVE_ARCH_HUGE_VMAP # arch supports the ioremap_pud_enabled() and ioremap_pmd_enabled() VM APIs
vm/ ioremap_prot : ok | HAVE_IOREMAP_PROT # arch has ioremap_prot()
vm/ numa-memblock : ok | HAVE_MEMBLOCK_NODE_MAP # arch supports NUMA aware memblocks
vm/ PG_uncached : ok | ARCH_USES_PG_UNCACHED # arch supports the PG_uncached page flag
vm/ pmdp_splitting_flush : ok | __HAVE_ARCH_PMDP_SPLITTING_FLUSH # arch supports the pmdp_splitting_flush() VM API
vm/ pte_special : ok | __HAVE_ARCH_PTE_SPECIAL # arch supports the pte_special()/pte_mkspecial() VM APIs
vm/ THP : ok | HAVE_ARCH_TRANSPARENT_HUGEPAGE # arch supports transparent hugepages
Cc: <linux-api@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
