diff mbox series

[bpf-next,v2,1/2] bpf: Remove a WARN_ON_ONCE warning related to local kptr

Message ID 20230824063417.201925-1-yonghong.song@linux.dev (mailing list archive)
State Accepted
Commit 393dc4bd92de3711012d791a93072c8cc94c4c57
Delegated to: BPF
Headers show
Series [bpf-next,v2,1/2] bpf: Remove a WARN_ON_ONCE warning related to local kptr | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR success PR summary
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netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for bpf-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1332 this patch: 1332
netdev/cc_maintainers warning 7 maintainers not CCed: kpsingh@kernel.org martin.lau@linux.dev john.fastabend@gmail.com sdf@google.com song@kernel.org jolsa@kernel.org haoluo@google.com
netdev/build_clang success Errors and warnings before: 1353 this patch: 1353
netdev/verify_signedoff success Signed-off-by tag matches author and committer
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netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1355 this patch: 1355
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 7 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
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Commit Message

Yonghong Song Aug. 24, 2023, 6:34 a.m. UTC 
Currently, in function bpf_obj_free_fields(), for local kptr,
a warning will be issued if the struct does not contain any
special fields. But actually the kernel seems totally okay
with a local kptr without any special fields. Permitting
no special fields also aligns with future percpu kptr which
also allows no special fields.

Acked-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
---
 kernel/bpf/syscall.c | 1 -
 1 file changed, 1 deletion(-)

NOTE: I didn't put a fix tag since except the warning
there is no correctness issue here.

Comments

patchwork-bot+netdevbpf@kernel.org Aug. 24, 2023, 3:20 p.m. UTC | #1 
Hello:

This series was applied to bpf/bpf-next.git (master)
by Alexei Starovoitov <ast@kernel.org>:

On Wed, 23 Aug 2023 23:34:17 -0700 you wrote:
> Currently, in function bpf_obj_free_fields(), for local kptr,
> a warning will be issued if the struct does not contain any
> special fields. But actually the kernel seems totally okay
> with a local kptr without any special fields. Permitting
> no special fields also aligns with future percpu kptr which
> also allows no special fields.
> 
> [...]

Here is the summary with links:
  - [bpf-next,v2,1/2] bpf: Remove a WARN_ON_ONCE warning related to local kptr
    https://git.kernel.org/bpf/bpf-next/c/393dc4bd92de
  - [bpf-next,v2,2/2] selftests/bpf: Add a local kptr test with no special fields
    https://git.kernel.org/bpf/bpf-next/c/001fedacc907

You are awesome, thank you!
diff mbox series

Patch

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 10666d17b9e3..ebeb0695305a 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -657,7 +657,6 @@  void bpf_obj_free_fields(const struct btf_record *rec, void *obj)
 			if (!btf_is_kernel(field->kptr.btf)) {
 				pointee_struct_meta = btf_find_struct_meta(field->kptr.btf,
 									   field->kptr.btf_id);
-				WARN_ON_ONCE(!pointee_struct_meta);
 				migrate_disable();
 				__bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ?
 								 pointee_struct_meta->record :