Avoid boxing errno during signal-frame setup - #15050
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This was found by the checkescape rewrite in #15033. |
CallWithSignalFrame runs without stack splitting from KVM's bluepill path, but converts a variable errno to error when rt_sigprocmask fails. Go emits runtime.convT64 for this conversion, which can grow the stack and allocate [1]. Even when an errno uses cached storage, the helper retains its stack check. The interface return was introduced in 374a11a. Return unix.Errno directly, with zero indicating success, and update bluepill to check the concrete result. The signal-handler test and benchmark now reject setup failures instead of silently accepting them and release their mapped stacks. [1]: https://github.com/golang/go/blob/go1.26.3/src/runtime/iface.go#L400-L408 Assisted-by: Codex
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@xinzhong could you please start the import? |
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CallWithSignalFrame runs without stack splitting from KVM's bluepill path, but converts a variable errno to error when rt_sigprocmask fails. Go emits runtime.convT64 for this conversion, which can grow the stack and allocate [1]. Even when an errno uses cached storage, the helper retains its stack check. The interface return was introduced in 374a11a. Return unix.Errno directly, with zero indicating success, and update bluepill to check the concrete result. The signal-handler test and benchmark now reject setup failures instead of silently accepting them and release their mapped stacks. [1]: https://github.com/golang/go/blob/go1.26.3/src/runtime/iface.go#L400-L408 Assisted-by: Codex FUTURE_COPYBARA_INTEGRATE_REVIEW=#15050 from tamird:sigframe-errno 5ea6855 PiperOrigin-RevId: 989285344
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CallWithSignalFrame runs without stack splitting from KVM's bluepill path, but converts a variable errno to error when rt_sigprocmask fails. Go emits runtime.convT64 for this conversion, which can grow the stack and allocate [1]. Even when an errno uses cached storage, the helper retains its stack check. The interface return was introduced in 374a11a. Return unix.Errno directly, with zero indicating success, and update bluepill to check the concrete result. The signal-handler test and benchmark now reject setup failures instead of silently accepting them and release their mapped stacks. [1]: https://github.com/golang/go/blob/go1.26.3/src/runtime/iface.go#L400-L408 Assisted-by: Codex FUTURE_COPYBARA_INTEGRATE_REVIEW=#15050 from tamird:sigframe-errno 5ea6855 PiperOrigin-RevId: 989285344
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CallWithSignalFrame runs without stack splitting from KVM's bluepill path, but converts a variable errno to error when rt_sigprocmask fails. Go emits runtime.convT64 for this conversion, which can grow the stack and allocate [1]. Even when an errno uses cached storage, the helper retains its stack check. The interface return was introduced in 374a11a. Return unix.Errno directly, with zero indicating success, and update bluepill to check the concrete result. The signal-handler test and benchmark now reject setup failures instead of silently accepting them and release their mapped stacks. [1]: https://github.com/golang/go/blob/go1.26.3/src/runtime/iface.go#L400-L408 Assisted-by: Codex FUTURE_COPYBARA_INTEGRATE_REVIEW=#15050 from tamird:sigframe-errno 5ea6855 PiperOrigin-RevId: 989285344
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CallWithSignalFrame runs without stack splitting from KVM's bluepill path, but converts a variable errno to error when rt_sigprocmask fails. Go emits runtime.convT64 for this conversion, which can grow the stack and allocate [1]. Even when an errno uses cached storage, the helper retains its stack check. The interface return was introduced in 374a11a. Return unix.Errno directly, with zero indicating success, and update bluepill to check the concrete result. The signal-handler test and benchmark now reject setup failures instead of silently accepting them and release their mapped stacks. [1]: https://github.com/golang/go/blob/go1.26.3/src/runtime/iface.go#L400-L408 Assisted-by: Codex FUTURE_COPYBARA_INTEGRATE_REVIEW=#15050 from tamird:sigframe-errno 5ea6855 PiperOrigin-RevId: 989285344
copybara-service Bot
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CallWithSignalFrame runs without stack splitting from KVM's bluepill path, but converts a variable errno to error when rt_sigprocmask fails. Go emits runtime.convT64 for this conversion, which can grow the stack and allocate [1]. Even when an errno uses cached storage, the helper retains its stack check. The interface return was introduced in 374a11a. Return unix.Errno directly, with zero indicating success, and update bluepill to check the concrete result. The signal-handler test and benchmark now reject setup failures instead of silently accepting them and release their mapped stacks. [1]: https://github.com/golang/go/blob/go1.26.3/src/runtime/iface.go#L400-L408 Assisted-by: Codex FUTURE_COPYBARA_INTEGRATE_REVIEW=#15050 from tamird:sigframe-errno 5ea6855 PiperOrigin-RevId: 989285344
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CallWithSignalFrame runs without stack splitting from KVM's bluepill path, but converts a variable errno to error when rt_sigprocmask fails. Go emits runtime.convT64 for this conversion, which can grow the stack and allocate 1. Even when an errno uses cached storage, the helper retains its stack check. The interface return was introduced in 374a11a.
Return unix.Errno directly, with zero indicating success, and update bluepill to check the concrete result. The signal-handler test and benchmark now reject setup failures instead of silently accepting them and release their mapped stacks.
Assisted-by: Codex