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Linux kernel
============
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Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
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.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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Radix tree header includes gfp.h for __GFP_BITS_SHIFT only. Now we
have gfp_types.h for this.
Fixes powerpc allmodconfig build:
In file included from include/linux/nodemask.h:97,
from include/linux/mmzone.h:17,
from include/linux/gfp.h:7,
from include/linux/radix-tree.h:12,
from include/linux/idr.h:15,
from include/linux/kernfs.h:12,
from include/linux/sysfs.h:16,
from include/linux/kobject.h:20,
from include/linux/pci.h:35,
from arch/powerpc/kernel/prom_init.c:24:
include/linux/random.h: In function 'add_latent_entropy':
>> include/linux/random.h:25:46: error: 'latent_entropy' undeclared (first use in this function); did you mean 'add_latent_entropy'?
25 | add_device_randomness((const void *)&latent_entropy, sizeof(latent_entropy));
| ^~~~~~~~~~~~~~
| add_latent_entropy
include/linux/random.h:25:46: note: each undeclared identifier is reported only once for each function it appears in
Reported-by: kernel test robot <lkp@intel.com>
CC: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs lseek fix from Al Viro:
"Fix proc_reg_llseek() breakage. Always had been possible if somebody
left NULL ->proc_lseek, became a practical issue now"
* tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
take care to handle NULL ->proc_lseek()
Pull more xen updates from Juergen Gross:
- fix the handling of the "persistent grants" feature negotiation
between Xen blkfront and Xen blkback drivers
- a cleanup of xen.config and adding xen.config to Xen section in
MAINTAINERS
- support HVMOP_set_evtchn_upcall_vector, which is more compliant to
"normal" interrupt handling than the global callback used up to now
- further small cleanups
* tag 'for-linus-6.0-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
MAINTAINERS: add xen config fragments to XEN HYPERVISOR sections
xen: remove XEN_SCRUB_PAGES in xen.config
xen/pciback: Fix comment typo
xen/xenbus: fix return type in xenbus_file_read()
xen-blkfront: Apply 'feature_persistent' parameter when connect
xen-blkback: Apply 'feature_persistent' parameter when connect
xen-blkback: fix persistent grants negotiation
x86/xen: Add support for HVMOP_set_evtchn_upcall_vector
Easily done now, just by clearing FMODE_LSEEK in ->f_mode
during proc_reg_open() for such entries.
Fixes: 868941b14441 "fs: remove no_llseek"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull more perf tool updates from Arnaldo Carvalho de Melo:
- 'perf c2c' now supports ARM64, adjust its output to cope with
differences with what is in x86_64. Now go find false sharing on
ARM64 (at least Neoverse) as well!
- Refactor the JSON processing, making the output more compact and thus
reducing the size of the resulting perf binary
- Improvements for 'perf offcpu' profiling, including tracking child
processes
- Update Intel JSON metrics and events files for broadwellde,
broadwellx, cascadelakex, haswellx, icelakex, ivytown, jaketown,
knightslanding, sapphirerapids, skylakex and snowridgex
- Add 'perf stat' JSON output and a 'perf test' entry for it
- Ignore memfd and anonymous mmap events if jitdump present
- Refactor 'perf test' shell tests allowing subdirs
- Fix an error handling path in 'parse_perf_probe_command()'
- Fixes for the guest Intel PT tracing patchkit in the 1st batch of
this merge window
- Print debuginfod queries if -v option is used, to explain delays in
processing when debuginfo servers are enabled to fetch DSOs with
richer symbol tables
- Improve error message for 'perf record -p not_existing_pid'
- Fix openssl and libbpf feature detection
- Add PMU pai_crypto event description for IBM z16 on 'perf list'
- Fix typos and duplicated words on comments in various places
* tag 'perf-tools-fixes-for-v6.0-2022-08-13' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (81 commits)
perf test: Refactor shell tests allowing subdirs
perf vendor events: Update events for snowridgex
perf vendor events: Update events and metrics for skylakex
perf vendor events: Update metrics for sapphirerapids
perf vendor events: Update events for knightslanding
perf vendor events: Update metrics for jaketown
perf vendor events: Update metrics for ivytown
perf vendor events: Update events and metrics for icelakex
perf vendor events: Update events and metrics for haswellx
perf vendor events: Update events and metrics for cascadelakex
perf vendor events: Update events and metrics for broadwellx
perf vendor events: Update metrics for broadwellde
perf jevents: Fold strings optimization
perf jevents: Compress the pmu_events_table
perf metrics: Copy entire pmu_event in find metric
perf pmu-events: Hide the pmu_events
perf pmu-events: Don't assume pmu_event is an array
perf pmu-events: Move test events/metrics to JSON
perf test: Use full metric resolution
perf pmu-events: Hide pmu_events_map
...
Make changes to the xen config fragments reach the XEN HYPERVISOR
maintainers and mailing list.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220810050712.9539-5-lukas.bulwahn@gmail.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Pull powerpc fixes from Michael Ellerman:
- Ensure we never emit lwarx with EH=1 on 32-bit, because some 32-bit
CPUs trap on it rather than ignoring it as they should.
- Fix ftrace when building with clang, which was broken by some
refactoring.
- A couple of other minor fixes.
Thanks to Christophe Leroy, Naveen N. Rao, Nick Desaulniers, Ondrej
Mosnacek, Pali Rohár, Russell Currey, and Segher Boessenkool.
* tag 'powerpc-6.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/kexec: Fix build failure from uninitialised variable
powerpc/ppc-opcode: Fix PPC_RAW_TW()
powerpc64/ftrace: Fix ftrace for clang builds
powerpc: Make eh value more explicit when using lwarx
powerpc: Don't hide eh field of lwarx behind a macro
powerpc: Fix eh field when calling lwarx on PPC32
This is a prelude to adding more tests to shell tests and in order to
support putting those tests into subdirectories, I need to change the
test code that scans/finds and runs them.
To support subdirs I have to recurse so it's time to refactor the code
to allow this and centralize the shell script finding into one location
and only one single scan that builds a list of all the found tests in
memory instead of it being duplicated in 3 places.
This code also optimizes things like knowing the max width of desciption
strings (as we can do that while we scan instead of a whole new pass of
opening files).
It also more cleanly filters scripts to see only *.sh files thus
skipping random other files in directories like *~ backup files, other
random junk/data files that may appear and the scripts must be
executable to make the cut (this ensures the script lib dir is not seen
as scripts to run).
This avoids perf test running previous older versions of test scripts
that are editor backup files as well as skipping perf.data files that
may appear and so on.
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Carsten Haitzler <carsten.haitzler@arm.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: coresight@lists.linaro.org
Link: https://lore.kernel.org/r/20220812121641.336465-2-carsten.haitzler@foss.arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 197ecb3802c0 ("xen/balloon: add runtime control for scrubbing
ballooned out pages") changed config XEN_SCRUB_PAGES to config
XEN_SCRUB_PAGES_DEFAULT. As xen.config sets 'XEN_BALLOON=y' and
XEN_SCRUB_PAGES_DEFAULT defaults to yes, there is no further need to set
this config in the xen.config file.
Remove setting XEN_SCRUB_PAGES in xen.config, which is without
effect since the commit above anyway.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220810050712.9539-3-lukas.bulwahn@gmail.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Pull /proc/mounts fix from Al Viro:
"Fix for /proc/mounts escaping - escape the '#' character too"
* tag 'pull-work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vfs: escape hash as well
clang 14 won't build because ret is uninitialised and can be returned if
both prop and fdtprop are NULL. Drop the ret variable and return an
error in that failure case.
Fixes: b1fc44eaa9ba ("pseries/iommu/ddw: Fix kdump to work in absence of ibm,dma-window")
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220810054331.373761-1-ruscur@russell.cc
Update the events to v1.20, update events for snowridgex by the latest
event converter tools.
Use script at:
https://github.com/intel/event-converter-for-linux-perf/blob/master/download_and_gen.py
to download and generate the latest events and metrics. Manually copy
the snowridgex files into perf.
Signed-off-by: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Tested-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220812085239.3089231-12-zhengjun.xing@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The double `the' is duplicated in the comment, remove one.
Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220811120918.17961-1-wangborong@cdjrlc.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Pull more cifs updates from Steve French:
- two fixes for stable, one for a lock length miscalculation, and
another fixes a lease break timeout bug
- improvement to handle leases, allows the close timeout to be
configured more safely
- five restructuring/cleanup patches
* tag '5.20-rc-smb3-client-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6:
cifs: Do not access tcon->cfids->cfid directly from is_path_accessible
cifs: Add constructor/destructors for tcon->cfid
SMB3: fix lease break timeout when multiple deferred close handles for the same file.
smb3: allow deferred close timeout to be configurable
cifs: Do not use tcon->cfid directly, use the cfid we get from open_cached_dir
cifs: Move cached-dir functions into a separate file
cifs: Remove {cifs,nfs}_fscache_release_page()
cifs: fix lock length calculation
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