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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The cond_resched() currently in the setup path needs to be duplicated in
the teardown path. Rather than require each instance of
for_each_device_pfn() to open code the same sequence, embed it in the
helper.
Link: https://github.com/intel/ixpdimm_sw/issues/11
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <stable@vger.kernel.org>
Fixes: 71389703839e ("mm, zone_device: Replace {get, put}_zone_device_page()...")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Re-enable deep flush so that users always have a way to be sure that a
write makes it all the way out to media. Writes from the PMEM driver
always arrive at the NVDIMM since movnt is used to bypass the cache, and
the driver relies on the ADR (Asynchronous DRAM Refresh) mechanism to
flush write buffers on power failure. The Deep Flush mechanism is there
to explicitly write buffers to protect against (rare) ADR failure. This
change prevents a regression in deep flush behavior so that applications
can continue to depend on fsync() as a mechanism to trigger deep flush
in the filesystem-DAX case.
Fixes: 06e8ccdab15f4 ("acpi: nfit: Add support for detect platform CPU cache...")
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Filesystem-DAX is incompatible with 'longterm' page pinning. Without
page cache indirection a DAX mapping maps filesystem blocks directly.
This means that the filesystem must not modify a file's block map while
any page in a mapping is pinned. In order to prevent the situation of
userspace holding of filesystem operations indefinitely, disallow
'longterm' Filesystem-DAX mappings.
RDMA has the same conflict and the plan there is to add a 'with lease'
mechanism to allow the kernel to notify userspace that the mapping is
being torn down for block-map maintenance. Perhaps something similar can
be put in place for vfio.
Note that xfs and ext4 still report:
"DAX enabled. Warning: EXPERIMENTAL, use at your own risk"
...at mount time, and resolving the dax-dma-vs-truncate problem is one
of the last hurdles to remove that designation.
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: kvm@vger.kernel.org
Cc: <stable@vger.kernel.org>
Reported-by: Haozhong Zhang <haozhong.zhang@intel.com>
Tested-by: Haozhong Zhang <haozhong.zhang@intel.com>
Fixes: d475c6346a38 ("dax,ext2: replace XIP read and write with DAX I/O")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Gerd reports that ->i_mode may contain other bits besides S_IFCHR. Use
S_ISCHR() instead. Otherwise, get_user_pages_longterm() may fail on
device-dax instances when those are meant to be explicitly allowed.
Fixes: 2bb6d2837083 ("mm: introduce get_user_pages_longterm")
Cc: <stable@vger.kernel.org>
Reported-by: Gerd Rausch <gerd.rausch@oracle.com>
Acked-by: Jane Chu <jane.chu@oracle.com>
Reported-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In Patch:
[7a862fb] brd: remove dax support
Dan Williams has removed the only might_sleep
implementation of ->direct_access.
So we no longer need to check for it.
CC: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Boaz Harrosh <boazh@netapp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull x86 Kconfig fixes from Thomas Gleixner:
"Three patchlets to correct HIGHMEM64G and CMPXCHG64 dependencies in
Kconfig when CPU selections are explicitely set to M586 or M686"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/Kconfig: Explicitly enumerate i686-class CPUs in Kconfig
x86/Kconfig: Exclude i586-class CPUs lacking PAE support from the HIGHMEM64G Kconfig group
x86/Kconfig: Add missing i586-class CPUs to the X86_CMPXCHG64 Kconfig group
Pull perf updates from Thomas Gleixner:
"Perf tool updates and kprobe fixes:
- perf_mmap overwrite mode fixes/overhaul, prep work to get 'perf
top' using it, making it bearable to use it in large core count
systems such as Knights Landing/Mill Intel systems (Kan Liang)
- s/390 now uses syscall.tbl, just like x86-64 to generate the
syscall table id -> string tables used by 'perf trace' (Hendrik
Brueckner)
- Use strtoull() instead of home grown function (Andy Shevchenko)
- Synchronize kernel ABI headers, v4.16-rc1 (Ingo Molnar)
- Document missing 'perf data --force' option (Sangwon Hong)
- Add perf vendor JSON metrics for ARM Cortex-A53 Processor (William
Cohen)
- Improve error handling and error propagation of ftrace based
kprobes so failures when installing kprobes are not silently
ignored and create disfunctional tracepoints"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
kprobes: Propagate error from disarm_kprobe_ftrace()
kprobes: Propagate error from arm_kprobe_ftrace()
Revert "tools include s390: Grab a copy of arch/s390/include/uapi/asm/unistd.h"
perf s390: Rework system call table creation by using syscall.tbl
perf s390: Grab a copy of arch/s390/kernel/syscall/syscall.tbl
tools/headers: Synchronize kernel ABI headers, v4.16-rc1
perf test: Fix test trace+probe_libc_inet_pton.sh for s390x
perf data: Document missing --force option
perf tools: Substitute yet another strtoull()
perf top: Check the latency of perf_top__mmap_read()
perf top: Switch default mode to overwrite mode
perf top: Remove lost events checking
perf hists browser: Add parameter to disable lost event warning
perf top: Add overwrite fall back
perf evsel: Expose the perf_missing_features struct
perf top: Check per-event overwrite term
perf mmap: Discard legacy interface for mmap read
perf test: Update mmap read functions for backward-ring-buffer test
perf mmap: Introduce perf_mmap__read_event()
perf mmap: Introduce perf_mmap__read_done()
...
The X86_P6_NOP config class leaves out many i686-class CPUs. Instead,
explicitly enumerate all these CPUs.
Using a configuration with M686 currently sets X86_MINIMUM_CPU_FAMILY=5
instead of the correct value of 6.
Booting on an i586 it will fail to generate the "This kernel
requires an i686 CPU, but only detected an i586 CPU" message and
intentional halt as expected. It will instead just silently hang
when it hits i686-specific instructions.
Signed-off-by: Matthew Whitehead <tedheadster@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
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: Josh Poimboeuf <jpoimboe@redhat.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/1518713696-11360-3-git-send-email-tedheadster@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull irq updates from Thomas Gleixner:
"A small set of updates mostly for irq chip drivers:
- MIPS GIC fix for spurious, masked interrupts
- fix for a subtle IPI bug in GICv3
- do not probe GICv3 ITSs that are marked as disabled
- multi-MSI support for GICv2m
- various small cleanups"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqdomain: Re-use DEFINE_SHOW_ATTRIBUTE() macro
irqchip/bcm: Remove hashed address printing
irqchip/gic-v2m: Add PCI Multi-MSI support
irqchip/gic-v3: Ignore disabled ITS nodes
irqchip/gic-v3: Use wmb() instead of smb_wmb() in gic_raise_softirq()
irqchip/gic-v3: Change pr_debug message to pr_devel
irqchip/mips-gic: Avoid spuriously handling masked interrupts
Improve error handling when disarming ftrace-based kprobes. Like with
arm_kprobe_ftrace(), propagate any errors from disarm_kprobe_ftrace() so
that we do not disable/unregister kprobes that are still armed. In other
words, unregister_kprobe() and disable_kprobe() should not report success
if the kprobe could not be disarmed.
disarm_all_kprobes() keeps its current behavior and attempts to
disarm all kprobes. It returns the last encountered error and gives a
warning if not all probes could be disarmed.
This patch is based on Petr Mladek's original patchset (patches 2 and 3)
back in 2015, which improved kprobes error handling, found here:
https://lkml.org/lkml/2015/2/26/452
However, further work on this had been paused since then and the patches
were not upstreamed.
Based-on-patches-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/20180109235124.30886-3-jeyu@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
i586-class machines also lack support for Physical Address Extension (PAE),
so add them to the exclusion list.
Signed-off-by: Matthew Whitehead <tedheadster@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
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: Josh Poimboeuf <jpoimboe@redhat.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/1518713696-11360-2-git-send-email-tedheadster@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull core fix from Thomas Gleixner:
"A small fix which adds the missing for_each_cpu_wrap() stub for the UP
case to avoid build failures"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpumask: Make for_each_cpu_wrap() available on UP as well