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Yonghong Song 14bb1e8c8d selftests/bpf: Fix flaky test btf_map_in_map/lookup_update
Recently, I frequently hit the following test failure:

  [root@arch-fb-vm1 bpf]# ./test_progs -n 33/1
  test_lookup_update:PASS:skel_open 0 nsec
  [...]
  test_lookup_update:PASS:sync_rcu 0 nsec
  test_lookup_update:FAIL:map1_leak inner_map1 leaked!
  #33/1    btf_map_in_map/lookup_update:FAIL
  #33      btf_map_in_map:FAIL

In the test, after map is closed and then after two rcu grace periods,
it is assumed that map_id is not available to user space.

But the above assumption cannot be guaranteed. After zero or one
or two rcu grace periods in different siturations, the actual
freeing-map-work is put into a workqueue. Later on, when the work
is dequeued, the map will be actually freed.
See bpf_map_put() in kernel/bpf/syscall.c.

By using workqueue, there is no ganrantee that map will be actually
freed after a couple of rcu grace periods. This patch removed
such map leak detection and then the test can pass consistently.

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240322061353.632136-1-yonghong.song@linux.dev
2024-03-25 17:25:54 +01:00
arch bpf: implement insn_is_cast_user() helper for JITs 2024-03-25 09:10:51 -07:00
block Revert "dm: use queue_limits_set" 2024-03-11 17:11:28 -07:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto crypto: lskcipher - Copy IV in lskcipher glue code always 2024-02-24 08:37:24 +08:00
Documentation Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
drivers Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
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include bpf: implement insn_is_cast_user() helper for JITs 2024-03-25 09:10:51 -07:00
init Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
io_uring for-6.9/io_uring-20240310 2024-03-11 11:35:31 -07:00
ipc shm: Slim down dependencies 2023-12-20 19:26:31 -05:00
kernel bpf: Avoid get_kernel_nofault() to fetch kprobe entry IP 2024-03-25 17:05:48 +01:00
lib Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
net bpf: Allow helper bpf_get_[ns_]current_pid_tgid() for all prog types 2024-03-19 14:24:07 -07:00
rust Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
samples Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
scripts Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
security Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
sound ASoC: Fixes for v6.8 2024-03-08 08:53:36 +01:00
tools selftests/bpf: Fix flaky test btf_map_in_map/lookup_update 2024-03-25 17:25:54 +01:00
usr Kbuild updates for v6.8 2024-01-18 17:57:07 -08:00
virt KVM: Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY 2024-02-22 17:07:06 -08:00
.clang-format clang-format: Update with v6.7-rc4's for_each macro list 2023-12-08 23:54:38 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.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 Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.mailmap Networking changes for 6.9. 2024-03-12 17:44:08 -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 vfs-6.9.ntfs 2024-03-11 09:55:17 -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 Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
Makefile Rust changes for v6.9 2024-03-11 12:31:28 -07:00
README README: Fix spelling/capitalization 2024-02-12 16:42:13 -07:00

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 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.