ext/opcache/jit: handle zend_jit_find_trace() failures #10153
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Commit 6c25413 added the flag ZEND_JIT_EXIT_INVALIDATE which resets the trace handlers in zend_jit_trace_exit(), but forgot to consider that on ZEND_JIT_TRACE_STOP_LINK, this changed handler gets passed to zend_jit_find_trace(), causing it to fail, either by returning 0 (results in bogus data) or by aborting due to ZEND_UNREACHABLE(). In either case, this crashes the PHP process. I'm not quite sure how to fix this multi-threading problem properly; my suggestion is to just fail the zend_jit_trace() call. After all, the whole ZEND_JIT_EXIT_INVALIDATE fix was about reloading modified scripts, so there's probably no point in this pending zend_jit_trace() call.
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dstogov
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Dec 26, 2022
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The patch looks fine. Thanks.
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Merged with b26b7589 thanks |
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Commit 6c25413 added the flag ZEND_JIT_EXIT_INVALIDATE which resets the trace handlers in zend_jit_trace_exit(), but forgot to consider that on ZEND_JIT_TRACE_STOP_LINK, this changed handler gets passed to zend_jit_find_trace(), causing it to fail, either by returning 0 (results in bogus data) or by aborting due to ZEND_UNREACHABLE(). In either case, this crashes the PHP process.
I'm not quite sure how to fix this multi-threading problem properly; my suggestion is to just fail the zend_jit_trace() call. After all, the whole ZEND_JIT_EXIT_INVALIDATE fix was about reloading modified scripts, so there's probably no point in this pending zend_jit_trace() call.