mirror of https://github.com/torvalds/linux.git
35b16a7a2c
perf_event__synthesize_modules() allocates a single union perf_event and reuses it across every kernel module callback. After the first module is processed, perf_record_mmap2__read_build_id() sets PERF_RECORD_MISC_MMAP_BUILD_ID in header.misc and writes that module's build ID into the event. On subsequent iterations the callback overwrites start, len, pid, and filename for the next module but never clears the stale build ID fields or the MMAP_BUILD_ID flag. When perf_record_mmap2__read_build_id() runs for the second module it sees the flag, reads the stale build ID into a dso_id, and __dso__improve_id() permanently poisons the DSO with the wrong build ID. Every module after the first therefore receives the first module's build ID in its MMAP2 record. On a system with the sunrpc and nfsd modules loaded, this causes perf script and perf report to show [unknown] for all module symbols. The latent bug has existed since commit |
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| .. | ||
| Documentation | ||
| arch | ||
| bench | ||
| check-header_ignore_hunks/lib | ||
| dlfilters | ||
| include/perf | ||
| jvmti | ||
| pmu-events | ||
| python | ||
| scripts | ||
| tests | ||
| trace | ||
| ui | ||
| util | ||
| .gitignore | ||
| Build | ||
| CREDITS | ||
| MANIFEST | ||
| Makefile | ||
| Makefile.config | ||
| Makefile.perf | ||
| builtin-annotate.c | ||
| builtin-bench.c | ||
| builtin-buildid-cache.c | ||
| builtin-buildid-list.c | ||
| builtin-c2c.c | ||
| builtin-check.c | ||
| builtin-config.c | ||
| builtin-daemon.c | ||
| builtin-data.c | ||
| builtin-diff.c | ||
| builtin-evlist.c | ||
| builtin-ftrace.c | ||
| builtin-help.c | ||
| builtin-inject.c | ||
| builtin-kallsyms.c | ||
| builtin-kmem.c | ||
| builtin-kvm.c | ||
| builtin-kwork.c | ||
| builtin-list.c | ||
| builtin-lock.c | ||
| builtin-mem.c | ||
| builtin-probe.c | ||
| builtin-record.c | ||
| builtin-report.c | ||
| builtin-sched.c | ||
| builtin-script.c | ||
| builtin-stat.c | ||
| builtin-timechart.c | ||
| builtin-top.c | ||
| builtin-trace.c | ||
| builtin-version.c | ||
| builtin.h | ||
| check-headers.sh | ||
| design.txt | ||
| perf-archive.sh | ||
| perf-completion.sh | ||
| perf-iostat.sh | ||
| perf-read-vdso.c | ||
| perf-sys.h | ||
| perf.c | ||
| perf.h | ||