Commit Graph

5996 Commits

Author SHA1 Message Date
David S. Miller
9f0ca0c1a5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-02-28

The following pull-request contains BPF updates for your *net-next* tree.

We've added 41 non-merge commits during the last 7 day(s) which contain
a total of 49 files changed, 1383 insertions(+), 499 deletions(-).

The main changes are:

1) BPF and Real-Time nicely co-exist.

2) bpftool feature improvements.

3) retrieve bpf_sk_storage via INET_DIAG.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-29 15:53:35 -08:00
David S. Miller
9f6e055907 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
The mptcp conflict was overlapping additions.

The SMC conflict was an additional and removal happening at the same
time.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-27 18:31:39 -08:00
Linus Torvalds
91ad64a84e Merge tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing and bootconfig updates:
 "Fixes and changes to bootconfig before it goes live in a release.

  Change in API of bootconfig (before it comes live in a release):
  - Have a magic value "BOOTCONFIG" in initrd to know a bootconfig
    exists
  - Set CONFIG_BOOT_CONFIG to 'n' by default
  - Show error if "bootconfig" on cmdline but not compiled in
  - Prevent redefining the same value
  - Have a way to append values
  - Added a SELECT BLK_DEV_INITRD to fix a build failure

  Synthetic event fixes:
  - Switch to raw_smp_processor_id() for recording CPU value in preempt
    section. (No care for what the value actually is)
  - Fix samples always recording u64 values
  - Fix endianess
  - Check number of values matches number of fields
  - Fix a printing bug

  Fix of trace_printk() breaking postponed start up tests

  Make a function static that is only used in a single file"

* tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  bootconfig: Fix CONFIG_BOOTTIME_TRACING dependency issue
  bootconfig: Add append value operator support
  bootconfig: Prohibit re-defining value on same key
  bootconfig: Print array as multiple commands for legacy command line
  bootconfig: Reject subkey and value on same parent key
  tools/bootconfig: Remove unneeded error message silencer
  bootconfig: Add bootconfig magic word for indicating bootconfig explicitly
  bootconfig: Set CONFIG_BOOT_CONFIG=n by default
  tracing: Clear trace_state when starting trace
  bootconfig: Mark boot_config_checksum() static
  tracing: Disable trace_printk() on post poned tests
  tracing: Have synthetic event test use raw_smp_processor_id()
  tracing: Fix number printing bug in print_synth_event()
  tracing: Check that number of vals matches number of synth event fields
  tracing: Make synth_event trace functions endian-correct
  tracing: Make sure synth_event_trace() example always uses u64
2020-02-26 10:34:42 -08:00
David Miller
6eac7795e8 bpf/tests: Use migrate disable instead of preempt disable
Replace the preemption disable/enable with migrate_disable/enable() to
reflect the actual requirement and to allow PREEMPT_RT to substitute it
with an actual migration disable mechanism which does not disable
preemption.

[ tglx: Switched it over to migrate disable ]

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.785306549@linutronix.de
2020-02-24 16:20:09 -08:00
Linus Torvalds
7031ecffab Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
 "This fixes a Kconfig-related build error and an integer overflow in
  chacha20poly1305"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: chacha20poly1305 - prevent integer overflow on large input
  tee: amdtee: amdtee depends on CRYPTO_DEV_CCP_DD
2020-02-24 11:40:23 -08:00
David S. Miller
e65ee2fb54 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflict resolution of ice_virtchnl_pf.c based upon work by
Stephen Rothwell.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-21 13:39:34 -08:00
Alexander Potapenko
305e519ce4 lib/stackdepot.c: fix global out-of-bounds in stack_slabs
Walter Wu has reported a potential case in which init_stack_slab() is
called after stack_slabs[STACK_ALLOC_MAX_SLABS - 1] has already been
initialized.  In that case init_stack_slab() will overwrite
stack_slabs[STACK_ALLOC_MAX_SLABS], which may result in a memory
corruption.

Link: http://lkml.kernel.org/r/20200218102950.260263-1-glider@google.com
Fixes: cd11016e5f ("mm, kasan: stackdepot implementation. Enable stackdepot for SLAB")
Signed-off-by: Alexander Potapenko <glider@google.com>
Reported-by: Walter Wu <walter-zh.wu@mediatek.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-21 11:22:15 -08:00
Alexandru Ardelean
c11d3fa011 lib/string.c: update match_string() doc-strings with correct behavior
There were a few attempts at changing behavior of the match_string()
helpers (i.e.  'match_string()' & 'sysfs_match_string()'), to change &
extend the behavior according to the doc-string.

But the simplest approach is to just fix the doc-strings.  The current
behavior is fine as-is, and some bugs were introduced trying to fix it.

As for extending the behavior, new helpers can always be introduced if
needed.

The match_string() helpers behave more like 'strncmp()' in the sense
that they go up to n elements or until the first NULL element in the
array of strings.

This change updates the doc-strings with this info.

Link: http://lkml.kernel.org/r/20200213072722.8249-1-alexandru.ardelean@analog.com
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Tobin C . Harding" <tobin@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-21 11:22:15 -08:00
Masami Hiramatsu
5f811c57c9 bootconfig: Add append value operator support
Add append value operator "+=" support to bootconfig syntax.
With this operator, user can add new value to the key as
an entry of array instead of overwriting.
For example,

  foo = bar
  ...
  foo += baz

Then the key "foo" has "bar" and "baz" values as an array.

Link: http://lkml.kernel.org/r/158227283195.12842.8310503105963275584.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-21 09:59:39 -05:00
Masami Hiramatsu
4e4694d872 bootconfig: Prohibit re-defining value on same key
Currently, bootconfig adds a new value on the existing key to the tail of an
array. But this looks a bit confusing because an admin can easily rewrite
the original value in the same config file.

This rejects the following value re-definition.

  key = value1
  ...
  key = value2

You should rewrite value1 to value2 in this case.

Link: http://lkml.kernel.org/r/158227282199.12842.10110929876059658601.stgit@devnote2

Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ Fixed spelling of arraies to arrays ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-21 09:59:19 -05:00
Masami Hiramatsu
a24d286f36 bootconfig: Reject subkey and value on same parent key
Reject if a value node is mixed with subkey node on same
parent key node.

A value node can not co-exist with subkey node under some key
node, e.g.

key = value
key.subkey = another-value

This is not be allowed because bootconfig API is not designed
to handle such case.

Link: http://lkml.kernel.org/r/158220115232.26565.7792340045009731803.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-20 17:54:09 -05:00
Gustavo A. R. Silva
1f4c51de33 lib: objagg: Replace zero-length arrays with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertenly introduced[3] to the codebase from now on.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-16 18:33:00 -08:00
Jason A. Donenfeld
c9cc0517bb crypto: chacha20poly1305 - prevent integer overflow on large input
This code assigns src_len (size_t) to sl (int), which causes problems
when src_len is very large. Probably nobody in the kernel should be
passing this much data to chacha20poly1305 all in one go anyway, so I
don't think we need to change the algorithm or introduce larger types
or anything. But we should at least error out early in this case and
print a warning so that we get reports if this does happen and can look
into why anybody is possibly passing it that much data or if they're
accidently passing -1 or similar.

Fixes: d95312a3cc ("crypto: lib/chacha20poly1305 - reimplement crypt_from_sg() routine")
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: stable@vger.kernel.org # 5.5+
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-02-14 14:48:37 +08:00
Linus Torvalds
61a7595403 Merge tag 'trace-v5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
 "Various fixes:

   - Fix an uninitialized variable

   - Fix compile bug to bootconfig userspace tool (in tools directory)

   - Suppress some error messages of bootconfig userspace tool

   - Remove unneded CONFIG_LIBXBC from bootconfig

   - Allocate bootconfig xbc_nodes dynamically. To ease complaints about
     taking up static memory at boot up

   - Use of parse_args() to parse bootconfig instead of strstr() usage
     Prevents issues of double quotes containing the interested string

   - Fix missing ring_buffer_nest_end() on synthetic event error path

   - Return zero not -EINVAL on soft disabled synthetic event (soft
     disabling must be the same as hard disabling, which returns zero)

   - Consolidate synthetic event code (remove duplicate code)"

* tag 'trace-v5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Consolidate trace() functions
  tracing: Don't return -EINVAL when tracing soft disabled synth events
  tracing: Add missing nest end to synth_event_trace_start() error case
  tools/bootconfig: Suppress non-error messages
  bootconfig: Allocate xbc_nodes array dynamically
  bootconfig: Use parse_args() to find bootconfig and '--'
  tracing/kprobe: Fix uninitialized variable bug
  bootconfig: Remove unneeded CONFIG_LIBXBC
  tools/bootconfig: Fix wrong __VA_ARGS__ usage
2020-02-11 16:39:18 -08:00
Masami Hiramatsu
a91e4f12ff bootconfig: Allocate xbc_nodes array dynamically
To reduce the large static array from kernel data, allocate
xbc_nodes array dynamically only if the kernel loads a
bootconfig.

Note that this also add dummy memblock.h for user-spacae
bootconfig tool.

Link: http://lkml.kernel.org/r/158108569699.3187.6512834527603883707.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-10 17:19:39 -05:00
Masami Hiramatsu
26445f98ea bootconfig: Remove unneeded CONFIG_LIBXBC
Since there is no user except CONFIG_BOOT_CONFIG and no plan
to use it from other functions, CONFIG_LIBXBC can be removed
and we can use CONFIG_BOOT_CONFIG directly.

Link: http://lkml.kernel.org/r/158098769281.939.16293492056419481105.stgit@devnote2

Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-10 12:07:42 -05:00
Linus Torvalds
89a47dd1af Merge tag 'kbuild-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:

 - fix randconfig to generate a sane .config

 - rename hostprogs-y / always to hostprogs / always-y, which are more
   natual syntax.

 - optimize scripts/kallsyms

 - fix yes2modconfig and mod2yesconfig

 - make multiple directory targets ('make foo/ bar/') work

* tag 'kbuild-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: make multiple directory targets work
  kconfig: Invalidate all symbols after changing to y or m.
  kallsyms: fix type of kallsyms_token_table[]
  scripts/kallsyms: change table to store (strcut sym_entry *)
  scripts/kallsyms: rename local variables in read_symbol()
  kbuild: rename hostprogs-y/always to hostprogs/always-y
  kbuild: fix the document to use extra-y for vmlinux.lds
  kconfig: fix broken dependency in randconfig-generated .config
2020-02-09 16:05:50 -08:00
Linus Torvalds
e310396bb8 Merge tag 'trace-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:

 - Added new "bootconfig".

   This looks for a file appended to initrd to add boot config options,
   and has been discussed thoroughly at Linux Plumbers.

   Very useful for adding kprobes at bootup.

   Only enabled if "bootconfig" is on the real kernel command line.

 - Created dynamic event creation.

   Merges common code between creating synthetic events and kprobe
   events.

 - Rename perf "ring_buffer" structure to "perf_buffer"

 - Rename ftrace "ring_buffer" structure to "trace_buffer"

   Had to rename existing "trace_buffer" to "array_buffer"

 - Allow trace_printk() to work withing (some) tracing code.

 - Sort of tracing configs to be a little better organized

 - Fixed bug where ftrace_graph hash was not being protected properly

 - Various other small fixes and clean ups

* tag 'trace-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (88 commits)
  bootconfig: Show the number of nodes on boot message
  tools/bootconfig: Show the number of bootconfig nodes
  bootconfig: Add more parse error messages
  bootconfig: Use bootconfig instead of boot config
  ftrace: Protect ftrace_graph_hash with ftrace_sync
  ftrace: Add comment to why rcu_dereference_sched() is open coded
  tracing: Annotate ftrace_graph_notrace_hash pointer with __rcu
  tracing: Annotate ftrace_graph_hash pointer with __rcu
  bootconfig: Only load bootconfig if "bootconfig" is on the kernel cmdline
  tracing: Use seq_buf for building dynevent_cmd string
  tracing: Remove useless code in dynevent_arg_pair_add()
  tracing: Remove check_arg() callbacks from dynevent args
  tracing: Consolidate some synth_event_trace code
  tracing: Fix now invalid var_ref_vals assumption in trace action
  tracing: Change trace_boot to use synth_event interface
  tracing: Move tracing selftests to bottom of menu
  tracing: Move mmio tracer config up with the other tracers
  tracing: Move tracing test module configs together
  tracing: Move all function tracing configs together
  tracing: Documentation for in-kernel synthetic event API
  ...
2020-02-06 07:12:11 +00:00
Masami Hiramatsu
0f0d0a77cc tools/bootconfig: Show the number of bootconfig nodes
Show the number of bootconfig nodes when applying new bootconfig to
initrd.

Since there are limitations of bootconfig not only in its filesize,
but also the number of nodes, the number should be shown when applying
so that user can get the feeling of scale of current bootconfig.

Link: http://lkml.kernel.org/r/158091061337.27924.10886706631693823982.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-05 17:17:05 -05:00
Masami Hiramatsu
597c0e3b45 bootconfig: Add more parse error messages
Add more error messages for following cases.
 - Exceeding max number of nodes
 - Config tree data is empty (e.g. comment only)
 - Config data is empty or exceeding max size
 - bootconfig is already initialized

Link: http://lkml.kernel.org/r/158091060401.27924.9024818742827122764.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-05 17:17:05 -05:00
Yury Norov
809e308f7f lib: new testcases for bitmap_parse{_user}
New version of bitmap_parse() is unified with bitmap_parse_list(),
and therefore:

- weakens rules on whitespaces and commas between hex chunks;

- in addition to

- allows passing UINT_MAX or any other big number as the length of input
  string instead of actual string length.

The patch covers the cases.

Link: http://lkml.kernel.org/r/20200102043031.30357-7-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Amritha Nambiar <amritha.nambiar@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: "Tobin C . Harding" <tobin@kernel.org>
Cc: Vineet Gupta <vineet.gupta1@synopsys.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:27 +00:00
Yury Norov
2d6261583b lib: rework bitmap_parse()
bitmap_parse() is ineffective and full of opaque variables and opencoded
parts.  It leads to hard understanding and usage of it.  This rework
includes:

- remove bitmap_shift_left() call from the cycle.  Now it makes the
  complexity of the algorithm as O(nbits^2).  In the suggested approach
  the input string is parsed in reverse direction, so no shifts needed;

- relax requirement on a single comma and no white spaces between
  chunks.  It is considered useful in scripting, and it aligns with
  bitmap_parselist();

- split bitmap_parse() to small readable helpers;

- make an explicit calculation of the end of input line at the
  beginning, so users of the bitmap_parse() won't bother doing this.

Link: http://lkml.kernel.org/r/20200102043031.30357-6-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Cc: Amritha Nambiar <amritha.nambiar@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: "Tobin C . Harding" <tobin@kernel.org>
Cc: Vineet Gupta <vineet.gupta1@synopsys.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Yury Norov
e66eda0615 lib: make bitmap_parse_user a wrapper on bitmap_parse
Currently we parse user data byte after byte which leads to
overcomplicating of parsing algorithm.  There are no performance critical
users of bitmap_parse_user(), and so we can duplicate user data to kernel
buffer and simply call bitmap_parselist().  This rework lets us unify and
simplify bitmap_parse() and bitmap_parse_user(), which is done in the
following patch.

Link: http://lkml.kernel.org/r/20200102043031.30357-5-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Amritha Nambiar <amritha.nambiar@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: "Tobin C . Harding" <tobin@kernel.org>
Cc: Vineet Gupta <vineet.gupta1@synopsys.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Yury Norov
7eb2e94e96 lib: add test for bitmap_parse()
The test is derived from bitmap_parselist() NO_LEN is reserved for use in
following patches.

[yury.norov@gmail.com: fix rebase issue]
  Link: http://lkml.kernel.org/r/20200102182659.6685-1-yury.norov@gmail.com
[andriy.shevchenko@linux.intel.com: fix address space when test user buffer]
  Link: http://lkml.kernel.org/r/20200109103601.45929-2-andriy.shevchenko@linux.intel.com
Link: http://lkml.kernel.org/r/20200102043031.30357-4-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Amritha Nambiar <amritha.nambiar@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: "Tobin C . Harding" <tobin@kernel.org>
Cc: Vineet Gupta <vineet.gupta1@synopsys.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Yury Norov
0bee0cece2 lib/string: add strnchrnul()
Patch series "lib: rework bitmap_parse", v5.

Similarl to the recently revisited bitmap_parselist(), bitmap_parse() is
ineffective and overcomplicated.  This series reworks it, aligns its
interface with bitmap_parselist() and makes it simpler to use.

The series also adds a test for the function and fixes usage of it in
cpumask_parse() according to the new design - drops the calculating of
length of an input string.

bitmap_parse() takes the array of numbers to be put into the map in the BE
order which is reversed to the natural LE order for bitmaps.  For example,
to construct bitmap containing a bit on the position 42, we have to put a
line '400,0'.  Current implementation reads chunk one by one from the
beginning ('400' before '0') and makes bitmap shift after each successful
parse.  It makes the complexity of the whole process as O(n^2).  We can do
it in reverse direction ('0' before '400') and avoid shifting, but it
requires reverse parsing helpers.

This patch (of 7):

New function works like strchrnul() with a length limited string.

Link: http://lkml.kernel.org/r/20200102043031.30357-2-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Amritha Nambiar <amritha.nambiar@intel.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Tobin C . Harding" <tobin@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Vineet Gupta <vineet.gupta1@synopsys.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00