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 --- drivers/gpu/host1x/debug.h | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 drivers/gpu/host1x/debug.h (limited to 'drivers/gpu/host1x/debug.h') diff --git a/drivers/gpu/host1x/debug.h b/drivers/gpu/host1x/debug.h new file mode 100644 index 000000000..c43c61d87 --- /dev/null +++ b/drivers/gpu/host1x/debug.h @@ -0,0 +1,45 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Tegra host1x Debug + * + * Copyright (c) 2011-2013 NVIDIA Corporation. + */ +#ifndef __HOST1X_DEBUG_H +#define __HOST1X_DEBUG_H + +#include +#include + +struct host1x; + +struct output { + void (*fn)(void *ctx, const char *str, size_t len, bool cont); + void *ctx; + char buf[256]; +}; + +static inline void write_to_seqfile(void *ctx, const char *str, size_t len, + bool cont) +{ + seq_write((struct seq_file *)ctx, str, len); +} + +static inline void write_to_printk(void *ctx, const char *str, size_t len, + bool cont) +{ + if (cont) + pr_cont("%s", str); + else + pr_info("%s", str); +} + +void __printf(2, 3) host1x_debug_output(struct output *o, const char *fmt, ...); +void __printf(2, 3) host1x_debug_cont(struct output *o, const char *fmt, ...); + +extern unsigned int host1x_debug_trace_cmdbuf; + +void host1x_debug_init(struct host1x *host1x); +void host1x_debug_deinit(struct host1x *host1x); +void host1x_debug_dump(struct host1x *host1x); + +#endif -- cgit v1.3.1