5.10-stable review patch. If anyone has any objections, please let me know.
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From: Shuai Xue xueshuai@linux.alibaba.com
Revert "perf hist: Add missing puts to hist__account_cycles"
This reverts commit a83fc293acd5c5050a4828eced4a71d2b2fffdd3.
On x86 platform, kernel v5.10.228, perf-report command aborts due to "free(): invalid pointer" when perf-record command is run with taken branch stack sampling enabled. This regression can be reproduced with the following steps:
- sudo perf record -b - sudo perf report
The root cause is that bi[i].to.ms.maps does not always point to thread->maps, which is a buffer dynamically allocated by maps_new(). Instead, it may point to &machine->kmaps, while kmaps is not a pointer but a variable. The original upstream commit c1149037f65b ("perf hist: Add missing puts to hist__account_cycles") worked well because machine->kmaps had been refactored to a pointer by the previous commit 1a97cee604dc ("perf maps: Use a pointer for kmaps").
To this end, just revert commit a83fc293acd5c5050a4828eced4a71d2b2fffdd3.
It is worth noting that the memory leak issue, which the reverted patch intended to fix, has been solved by commit cf96b8e45a9b ("perf session: Add missing evlist__delete when deleting a session"). The root cause is that the evlist is not being deleted on exit in perf-report, perf-script, and perf-data. Consequently, the reference count of the thread increased by thread__get() in hist_entry__init() is not decremented in hist_entry__delete(). As a result, thread->maps is not properly freed.
Cc: Adrian Hunter adrian.hunter@intel.com Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Ian Rogers irogers@google.com Cc: Mark Rutland mark.rutland@arm.com Cc: Namhyung Kim namhyung@kernel.org Cc: Peter Zijlstra peterz@infradead.org Cc: Arnaldo Carvalho de Melo acme@redhat.com Cc: K Prateek Nayak kprateek.nayak@amd.com Cc: Ravi Bangoria ravi.bangoria@amd.com Cc: Sandipan Das sandipan.das@amd.com Cc: Anshuman Khandual anshuman.khandual@arm.com Cc: German Gomez german.gomez@arm.com Cc: James Clark james.clark@arm.com Cc: Nick Terrell terrelln@fb.com Cc: Sean Christopherson seanjc@google.com Cc: Changbin Du changbin.du@huawei.com Cc: liuwenyu liuwenyu7@huawei.com Cc: Yang Jihong yangjihong1@huawei.com Cc: Masami Hiramatsu mhiramat@kernel.org Cc: Miguel Ojeda ojeda@kernel.org Cc: Song Liu song@kernel.org Cc: Leo Yan leo.yan@linaro.org Cc: Kajol Jain kjain@linux.ibm.com Cc: Andi Kleen ak@linux.intel.com Cc: Kan Liang kan.liang@linux.intel.com Cc: Athira Rajeev atrajeev@linux.vnet.ibm.com Cc: Yanteng Si siyanteng@loongson.cn Cc: Liam Howlett liam.howlett@oracle.com Cc: Paolo Bonzini pbonzini@redhat.com Cc: stable@vger.kernel.org # 5.10.228 Signed-off-by: Shuai Xue xueshuai@linux.alibaba.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/perf/util/hist.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-)
--- a/tools/perf/util/hist.c +++ b/tools/perf/util/hist.c @@ -2624,6 +2624,8 @@ void hist__account_cycles(struct branch_
/* If we have branch cycles always annotate them. */ if (bs && bs->nr && entries[0].flags.cycles) { + int i; + bi = sample__resolve_bstack(sample, al); if (bi) { struct addr_map_symbol *prev = NULL; @@ -2638,7 +2640,7 @@ void hist__account_cycles(struct branch_ * Note that perf stores branches reversed from * program order! */ - for (int i = bs->nr - 1; i >= 0; i--) { + for (i = bs->nr - 1; i >= 0; i--) { addr_map_symbol__account_cycles(&bi[i].from, nonany_branch_mode ? NULL : prev, bi[i].flags.cycles); @@ -2647,12 +2649,6 @@ void hist__account_cycles(struct branch_ if (total_cycles) *total_cycles += bi[i].flags.cycles; } - for (unsigned int i = 0; i < bs->nr; i++) { - map__put(bi[i].to.ms.map); - maps__put(bi[i].to.ms.maps); - map__put(bi[i].from.ms.map); - maps__put(bi[i].from.ms.maps); - } free(bi); } }