Linux kernel stable tree
Go to file
Aditya Gupta 1a5efc9e13 libsubcmd: Don't free the usage string
Currently, commands which depend on 'parse_options_subcommand()' don't
show the usage string, and instead show '(null)'

    $ ./perf sched
	Usage: (null)

    -D, --dump-raw-trace  dump raw trace in ASCII
    -f, --force           don't complain, do it
    -i, --input <file>    input file name
    -v, --verbose         be more verbose (show symbol address, etc)

'parse_options_subcommand()' is generally expected to initialise the usage
string, with information in the passed 'subcommands[]' array

This behaviour was changed in:

  230a7a71f9 ("libsubcmd: Fix parse-options memory leak")

Where the generated usage string is deallocated, and usage[0] string is
reassigned as NULL.

As discussed in [1], free the allocated usage string in the main
function itself, and don't reset usage string to NULL in
parse_options_subcommand

With this change, the behaviour is restored.

    $ ./perf sched
        Usage: perf sched [<options>] {record|latency|map|replay|script|timehist}

           -D, --dump-raw-trace  dump raw trace in ASCII
           -f, --force           don't complain, do it
           -i, --input <file>    input file name
           -v, --verbose         be more verbose (show symbol address, etc)

[1]: https://lore.kernel.org/linux-perf-users/htq5vhx6piet4nuq2mmhk7fs2bhfykv52dbppwxmo3s7du2odf@styd27tioc6e/

Fixes: 230a7a71f9 ("libsubcmd: Fix parse-options memory leak")
Suggested-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Disha Goel <disgoel@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240904061836.55873-2-adityag@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-09-04 09:54:24 -03:00
arch RISC-V Fixes for 6.11-rc4 2024-08-16 11:18:09 -07:00
block block: Fix lockdep warning in blk_mq_mark_tag_wait 2024-08-15 19:25:03 -06:00
certs kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
crypto crypto: testmgr - generate power-of-2 lengths more often 2024-07-13 11:50:28 +12:00
Documentation Devicetree fixes for v6.11, part 2: 2024-08-16 13:50:33 -07:00
drivers block-6.11-20240824 2024-08-16 14:03:31 -07:00
fs for-6.11-rc3-tag 2024-08-14 17:56:15 -07:00
include io_uring-6.11-20240824 2024-08-16 14:00:05 -07:00
init Rust fixes for v6.11 2024-08-16 11:24:06 -07:00
io_uring io_uring/sqpoll: annotate debug task == current with data_race() 2024-08-13 06:10:59 -06:00
ipc sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
kernel A couple of fixes for tracing: 2024-08-16 11:12:29 -07:00
lib kunit/overflow: Fix UB in overflow_allocation_test 2024-08-15 09:24:55 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm 9 hotfixes. 5 are cc:stable, 4 either pertain to post-6.10 material or 2024-08-08 07:32:20 -07:00
net Including fixes from wireless and netfilter 2024-08-15 10:35:20 -07:00
rust Rust fixes for v6.11 2024-08-16 11:24:06 -07:00
samples Driver core changes for 6.11-rc1 2024-07-25 10:42:22 -07:00
scripts Rust fixes for v6.11 2024-08-16 11:24:06 -07:00
security KEYS: trusted: dcp: fix leak of blob encryption key 2024-08-15 22:01:14 +03:00
sound ALSA: hda/tas2781: Use correct endian conversion 2024-08-14 16:58:26 +02:00
tools libsubcmd: Don't free the usage string 2024-09-04 09:54:24 -03:00
usr initramfs: shorten cmd_initfs in usr/Makefile 2024-07-16 01:07:52 +09:00
virt KVM: x86: Disallow read-only memslots for SEV-ES and SEV-SNP (and TDX) 2024-08-14 12:28:24 -04:00
.clang-format Docs: Move clang-format from process/ to dev-tools/ 2024-06-26 16:36:00 -06:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: add script and target to generate pacman package 2024-07-22 01:24:22 +09:00
.mailmap mailmap: update entry for David Heidelberg 2024-08-07 18:33:56 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS tracing: Update of MAINTAINERS and CREDITS file 2024-07-18 14:08:42 -07:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS sound fixes for 6.11-rc3 2024-08-09 09:25:30 -07:00
Makefile Rust fixes for v6.11 2024-08-16 11:24:06 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText 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.