From 2b97956af60810cd382b86b9ce9aea421b889861 Mon Sep 17 00:00:00 2001 From: Nuoqi Gui Date: Fri, 4 Sep 2026 12:41:55 +0200 Subject: selftests/bpf: Test rhtab kptr cancellation semantics 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 [ kkd: Split update and delete coverage and rewrote the commit log ] Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260904104203.345917-5-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- include/asm-generic/string.h | 10 ++++++++++ 1 file changed, 10 insertions(+) create mode 100644 include/asm-generic/string.h (limited to 'include/asm-generic/string.h') diff --git a/include/asm-generic/string.h b/include/asm-generic/string.h new file mode 100644 index 000000000..de5e02014 --- /dev/null +++ b/include/asm-generic/string.h @@ -0,0 +1,10 @@ +#ifndef __ASM_GENERIC_STRING_H +#define __ASM_GENERIC_STRING_H +/* + * The kernel provides all required functions in lib/string.c + * + * Architectures probably want to provide at least their own optimized + * memcpy and memset functions though. + */ + +#endif /* __ASM_GENERIC_STRING_H */ -- cgit v1.3.1