bpf: Reduce verifier stack frame size #9246
Closed
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
![kernel-patches-daemon-bpf[bot]](https://avatars.githubusercontent.com/u/70728002?s=60&v=4){kind=small}
|
Upstream branch: 564606f |
kernel-patches-daemon-bpf
bot
force-pushed
the
bpf-next_base
branch
from
6fbb3d3 to
08dbf36
Compare
|
Upstream branch: 38d95be |
kernel-patches-daemon-bpf
bot
force-pushed
the
series/978313=>bpf-next
branch
from
f9cf02f to
ad47714
Compare
|
Upstream branch: 38d95be |
kernel-patches-daemon-bpf
bot
force-pushed
the
series/978313=>bpf-next
branch
from
ad47714 to
6e34678
Compare
|
Upstream branch: 38d95be |
kernel-patches-daemon-bpf
bot
force-pushed
the
series/978313=>bpf-next
branch
from
6e34678 to
eff30a1
Compare
|
Upstream branch: 38d95be |
kernel-patches-daemon-bpf
bot
force-pushed
the
series/978313=>bpf-next
branch
from
eff30a1 to
6d49e2e
Compare
kernel-patches-daemon-bpf
bot
force-pushed
the
bpf-next_base
branch
from
08dbf36 to
cc01c15
Compare
|
Upstream branch: 38d95be |
kernel-patches-daemon-bpf
bot
force-pushed
the
series/978313=>bpf-next
branch
from
6d49e2e to
279f98e
Compare
|
Upstream branch: 38d95be |
kernel-patches-daemon-bpf
bot
force-pushed
the
series/978313=>bpf-next
branch
from
279f98e to
a5beedc
Compare
kernel-patches-daemon-bpf
bot
force-pushed
the
bpf-next_base
branch
from
cc01c15 to
901b4c5
Compare
|
Upstream branch: 1f24c0d |
added 3 commits
July 3, 2025 15:30
In verifier.c, the following code patterns (in two places) struct bpf_insn *patch = &insn_buf[0]; can be simplified to struct bpf_insn *patch = insn_buf; which is easier to understand. Acked-by: Eduard Zingerman <[email protected]> Signed-off-by: Yonghong Song <[email protected]>
Arnd Bergmann reported an issue ([1]) where clang compiler (less than
llvm18) may trigger an error where the stack frame size exceeds the limit.
I can reproduce the error like below:
kernel/bpf/verifier.c:24491:5: error: stack frame size (2552) exceeds limit (1280) in 'bpf_check'
[-Werror,-Wframe-larger-than]
kernel/bpf/verifier.c:19921:12: error: stack frame size (1368) exceeds limit (1280) in 'do_check'
[-Werror,-Wframe-larger-than]
Use env->insn_buf for bpf insns instead of putting these insns on the
stack. This can resolve the above 'bpf_check' error. The 'do_check' error
will be resolved in the next patch.
[1] https://lore.kernel.org/bpf/[email protected]/
Reported-by: Arnd Bergmann <[email protected]>
Tested-by: Arnd Bergmann <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Acked-by: Eduard Zingerman <[email protected]>
Signed-off-by: Yonghong Song <[email protected]>
Add a 'struct bpf_scc_callchain callchain_buf' field in bpf_verifier_env.
This way, the previous bpf_scc_callchain local variables can be
replaced by taking address of env->callchain_buf. This can reduce stack
usage and fix the following error:
kernel/bpf/verifier.c:19921:12: error: stack frame size (1368) exceeds limit (1280) in 'do_check'
[-Werror,-Wframe-larger-than]
Reported-by: Arnd Bergmann <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Acked-by: Eduard Zingerman <[email protected]>
Signed-off-by: Yonghong Song <[email protected]>
kernel-patches-daemon-bpf
bot
force-pushed
the
series/978313=>bpf-next
branch
from
a5beedc to
dbc3d1d
Compare
kernel-patches-daemon-bpf
bot
force-pushed
the
bpf-next_base
branch
from
901b4c5 to
fa8c3a1
Compare
|
At least one diff in series https://patchwork.kernel.org/project/netdevbpf/list/?series=978662 irrelevant now. Closing PR. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Pull request for series with
subject: bpf: Reduce verifier stack frame size
version: 2
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=978313