Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.
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Make the function get_user_bd_entry() static as it is not used outside of
arch/x86/mm/mpx.c
This fixes a sparse warning.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The rdtgroup_kn_unlock waits for the last user to release and put its
node. But it's calling kernfs_put on the node which calls the
rdtgroup_kn_unlock, which might not be the group's directory node, but
another group's file node.
This race could be easily reproduced by running 2 instances
of following script:
mount -t resctrl resctrl /sys/fs/resctrl/
pushd /sys/fs/resctrl/
mkdir krava
echo "krava" > krava/schemata
rmdir krava
popd
umount /sys/fs/resctrl
It triggers the slub debug error message with following command
line config: slub_debug=,kernfs_node_cache.
Call kernfs_put on the group's node to fix it.
Fixes: 60cf5e101fd4 ("x86/intel_rdt: Add mkdir to resctrl file system")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Shaohua Li <shli@fb.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1489501253-20248-1-git-send-email-jolsa@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pavel Machek reported the following warning on x86-32:
WARNING: kernel stack frame pointer at f50cdf98 in swapper/2:0 has bad value (null)
The warning is caused by the unwinder not realizing that it reached the
end of the stack, due to an unusual prologue which gcc sometimes
generates for aligned stacks. The prologue is based on a gcc feature
called the Dynamic Realign Argument Pointer (DRAP). It's almost always
enabled for aligned stacks when -maccumulate-outgoing-args isn't set.
This issue is similar to the one fixed by the following commit:
8023e0e2a48d ("x86/unwind: Adjust last frame check for aligned function stacks")
... but that fix was specific to x86-64.
Make the fix more generic to cover x86-32 as well, and also ensure that
the return address referred to by the frame pointer is a copy of the
original return address.
Fixes: acb4608ad186 ("x86/unwind: Create stack frames for saved syscall registers")
Reported-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/50d4924db716c264b14f1633037385ec80bf89d2.1489465609.git.jpoimboe@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We still get a build error in random configurations, after this has been
modified a few times:
In file included from include/linux/mm.h:68:0,
from include/linux/suspend.h:8,
from arch/x86/kernel/asm-offsets.c:12:
arch/x86/include/asm/pgtable.h:66:26: error: redefinition of 'native_pud_clear'
#define pud_clear(pud) native_pud_clear(pud)
My interpretation is that the build error comes from a typo in __PAGETABLE_PUD_FOLDED,
so fix that typo now, and remove the incorrect #ifdef around the native_pud_clear
definition.
Fixes: 3e761a42e19c ("mm, x86: fix HIGHMEM64 && PARAVIRT build config for native_pud_clear()")
Fixes: a00cc7d9dd93 ("mm, x86: add support for PUD-sized transparent hugepages")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Thomas Garnier <thgarnie@google.com>
Link: http://lkml.kernel.org/r/20170314121330.182155-1-arnd@arndb.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The kernel doesn't boot with both PROFILE_ANNOTATED_BRANCHES=y and KASAN=y
options selected. With branch profiling enabled we end up calling
ftrace_likely_update() before kasan_early_init(). ftrace_likely_update() is
built with KASAN instrumentation, so calling it before kasan has been
initialized leads to crash.
Use DISABLE_BRANCH_PROFILING define to make sure that we don't call
ftrace_likely_update() from early code before kasan_early_init().
Fixes: ef7f0d6a6ca8 ("x86_64: add KASan support")
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: kasan-dev@googlegroups.com
Cc: Alexander Potapenko <glider@google.com>
Cc: stable@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: lkp@01.org
Cc: Dmitry Vyukov <dvyukov@google.com>
Link: http://lkml.kernel.org/r/20170313163337.1704-1-aryabinin@virtuozzo.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Intel Merrifield platform has a Basin Cove PMIC to handle in particular
power button events. Add necessary bits to enable it.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170308112422.67533-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Intel Medfield may use common for Intel MID devices power sequence.
Remove unneded custom power off stub.
While here, remove function forward declaration.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170308112422.67533-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Remove the WARNING message associated with multiple NMI handlers as
there are at least two that are legitimate. These are the KGDB and the
UV handlers and both want to be called if the NMI has not been claimed
by any other NMI handler.
Use of the UNKNOWN NMI call chain dramatically lowers the NMI call rate
when high frequency NMI tools are in use, notably the perf tools. It is
required on systems that cannot sustain a high NMI call rate without
adversely affecting the system operation.
Signed-off-by: Mike Travis <mike.travis@hpe.com>
Reviewed-by: Dimitri Sivanich <dimitri.sivanich@hpe.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Russ Anderson <russ.anderson@hpe.com>
Cc: Frank Ramsay <frank.ramsay@hpe.com>
Cc: Tony Ernst <tony.ernst@hpe.com>
Link: http://lkml.kernel.org/r/20170307210841.730959611@asylum.americas.sgi.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Subhransu reported that convert_art_to_tsc() isn't working for him.
The ART to TSC relation is only set up for systems which use the refined
TSC calibration. Systems with known TSC frequency (available via CPUID 15)
are not using the refined calibration and therefor the ART to TSC relation
is never established.
Add the setup to the known frequency init path which skips ART
calibration. The init code needs to be duplicated as for systems which use
refined calibration the ART setup must be delayed until calibration has
been done.
The problem has been there since the ART support was introdduced, but only
detected now because Subhransu tested the first time on hardware which has
TSC frequency enumerated via CPUID 15.
Note for stable: The conditional has changed from TSC_RELIABLE to
TSC_KNOWN_FREQUENCY.
[ tglx: Rewrote changelog and identified the proper 'Fixes' commit ]
Fixes: f9677e0f8308 ("x86/tsc: Always Running Timer (ART) correlated clocksource")
Reported-by: "Prusty, Subhransu S" <subhransu.s.prusty@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Cc: christopher.s.hall@intel.com
Cc: kevin.b.stanton@intel.com
Cc: john.stultz@linaro.org
Cc: akataria@vmware.com
Link: http://lkml.kernel.org/r/20170313145712.GI3312@twins.programming.kicks-ass.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The interrupt line used for the watchdog is 12, according to the official
Intel Edison BSP code.
And indeed after fixing it we start getting an interrupt and thus the
watchdog starts working again:
[ 191.699951] Kernel panic - not syncing: Kernel Watchdog
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Cohen <david.a.cohen@linux.intel.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>
Fixes: 78a3bb9e408b ("x86: intel-mid: add watchdog platform code for Merrifield")
Link: http://lkml.kernel.org/r/20170312150744.45493-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull s390 fixes from Martin Schwidefsky:
- four patches to get the new cputime code in shape for s390
- add the new statx system call
- a few bug fixes
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390: wire up statx system call
KVM: s390: Fix guest migration for huge guests resulting in panic
s390/ipl: always use load normal for CCW-type re-IPL
s390/timex: micro optimization for tod_to_ns
s390/cputime: provide archicture specific cputime_to_nsecs
s390/cputime: reset all accounting fields on fork
s390/cputime: remove last traces of cputime_t
s390: fix in-kernel program checks
s390/crypt: fix missing unlock in ctr_paes_crypt on error path
Pull x86 fixes from Thomas Gleixner:
- a fix for the kexec/purgatory regression which was introduced in the
merge window via an innocent sparse fix. We could have reverted that
commit, but on deeper inspection it turned out that the whole
machinery is neither documented nor robust. So a proper cleanup was
done instead
- the fix for the TLB flush issue which was discovered recently
- a simple typo fix for a reboot quirk
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tlb: Fix tlb flushing when lguest clears PGE
kexec, x86/purgatory: Unbreak it and clean it up
x86/reboot/quirks: Fix typo in ASUS EeeBook X205TA reboot quirk