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| author | Nuoqi Gui <gnq25@mails.tsinghua.edu.cn> | 2026-09-04 12:41:55 +0200 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2026-09-04 12:24:25 -0700 |
| commit | 2b97956af60810cd382b86b9ce9aea421b889861 (patch) | |
| tree | 7d9b0d8a91f77e63deff23976f68555a4895346a /tools/testing/selftests/locking | |
| download | linux-stable-2b97956af60810cd382b86b9ce9aea421b889861.tar.gz linux-stable-2b97956af60810cd382b86b9ce9aea421b889861.zip | |
selftests/bpf: Test rhtab kptr cancellation semanticsgrafted
Resizable hash-map updates and deletions must not perform full special-field
destruction in their caller context. In particular, a referenced kptr must
remain attached to the allocation until the memory allocator destructor can
release it safely.
Add separate coverage for both affected paths. The update test stores a task
kptr, replaces the ordinary value bytes with BPF_EXIST, and verifies that the
kptr survived. The delete test removes an element and exchanges its kptr
through the still-valid map-value pointer before the allocation is reclaimed.
Both cases observe a NULL kptr when rhtab uses bpf_obj_free_fields(). They
recover and release the reference after rhtab switches to cancellation
semantics.
Signed-off-by: Nuoqi Gui <gnq25@mails.tsinghua.edu.cn>
[ kkd: Split update and delete coverage and rewrote the commit log ]
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20260904104203.345917-5-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/testing/selftests/locking')
| -rw-r--r-- | tools/testing/selftests/locking/Makefile | 10 | ||||
| -rwxr-xr-x | tools/testing/selftests/locking/ww_mutex.sh | 19 |
2 files changed, 29 insertions, 0 deletions
diff --git a/tools/testing/selftests/locking/Makefile b/tools/testing/selftests/locking/Makefile new file mode 100644 index 000000000..6e7761ab3 --- /dev/null +++ b/tools/testing/selftests/locking/Makefile @@ -0,0 +1,10 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for locking/ww_mutx selftests + +# No binaries, but make sure arg-less "make" doesn't trigger "run_tests" +all: + +TEST_PROGS := ww_mutex.sh + +include ../lib.mk diff --git a/tools/testing/selftests/locking/ww_mutex.sh b/tools/testing/selftests/locking/ww_mutex.sh new file mode 100755 index 000000000..91e4ac756 --- /dev/null +++ b/tools/testing/selftests/locking/ww_mutex.sh @@ -0,0 +1,19 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 + +# Kselftest framework requirement - SKIP code is 4. +ksft_skip=4 + +# Runs API tests for struct ww_mutex (Wait/Wound mutexes) +if ! /sbin/modprobe -q -n test-ww_mutex; then + echo "ww_mutex: module test-ww_mutex is not found [SKIP]" + exit $ksft_skip +fi + +if /sbin/modprobe -q test-ww_mutex; then + /sbin/modprobe -q -r test-ww_mutex + echo "locking/ww_mutex: ok" +else + echo "locking/ww_mutex: [FAIL]" + exit 1 +fi |