Repository navigation
Conversation
Add AGENT documentation.
handle_s answered every single-step ('s') with a SIGTERM stop-reply
whenever ql.emu_state was QL_STATE.STOPPED. But emu_start always leaves
the state STOPPED after running the requested step count, so the guard
was true on every step and gdb clients saw a spurious termination signal,
disconnecting mid-debug (issues #1377, #1538).
Give handle_s the same exit-vs-trap discrimination handle_c already uses:
a step reports SIGTRAP unless it carried pc to the emulation exit point,
in which case the guest has actually terminated and we reply W{exit_code}.
Also wrap the step in the same UcError/KeyboardInterrupt handling as
handle_c so a fault while stepping maps to a signal instead of crashing
the stub, and hoist the shared uc-error->signal map to a module constant.
Add a regression test that single-steps over the gdb stub and asserts the
stop-reply is 'S05' (SIGTRAP), which fails as 'S0f' (SIGTERM) without the fix.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The stub drove continue by calling emu_start synchronously and only read the socket again once the target stopped on its own, so the bare \x03 break byte a client sends to pause a running target was never seen. A guest that free-runs (e.g. an idle/event loop) could not be interrupted at all -- gdb/Ghidra reported 'Cannot execute this command while the target is running'. Poll the client socket for the break byte from the per-instruction run hook (dbg_hook), which does run on the emulation thread during emu_start: - GdbSerialConn.poll_interrupt(): non-blocking select+recv, True on \x03. - QlGdbUtils.dbg_hook: throttled (every INTR_POLL_INTERVAL insns) check of an installed check_interrupt callback; on a break, stop emulation and record it. - handle_c: reply SIGINT when the stop was an interrupt rather than a breakpoint or normal exit. Add a regression test that lets an infinite-loop guest free-run, sends the bare break byte and asserts the stop-reply is 'S02' (SIGINT). Without the fix no reply ever arrives, so the test stops the guest itself and fails rather than hanging the run. Also verified against a free-running MIPS64 BE guest: \x03 -> S02 in <1ms. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
A client that resumes while a signal is pending sends a vCont action of the form 'C<sig>' (continue and deliver) or 'S<sig>' (step and deliver), e.g. 'vCont;S0f:pa410.1996;c:pa410.-1' -- the exact packet reported in issue #1377. handle_v matched only 'c'/'C05' and 's'/'S05', so any other signal fell through to an empty reply and clients aborted the session with 'Invalid remote reply:'. We do not deliver host signals to the guest, so the signal value carries no meaning for us: accept any of them and carry the action out as a plain resume or step, which is what the client asked for. This matters more now that the stub can stop with SIGINT on an async interrupt, since a client may well resume from such a stop with 'C02'. Also stop assuming os.exit_code exists when reporting termination: bare-metal os layers (QlOsMcu) do not define it, which turns the exit path into an AttributeError (seen in issue #1276). The underlying MCU interrupt handling of #1276 is out of scope here. Add a regression test asserting the '#1377' packet is answered with a SIGTRAP stop-reply and that a signalled continue runs the guest to termination; both replies are empty without the fix. Fixes #1377 Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
gdb: fix stop-replies for step, signalled vCont resume, and ctrl-c interrupt
update new ARCHITECTURE docs
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
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.
Checklist
Which kind of PR do you create?
Coding convention?
Extra tests?
Changelog?
Target branch?
One last thing