Currently, the initialization of loongarch_jump_ops does not contain an
assignment to its .free field. This causes disasm_line__free() to fall
through to ins_ops__delete() for LoongArch jump instructions.
ins_ops__delete() will free ins_operands.source.raw and
ins_operands.source.name, and these fields overlaps with
ins_operands.jump.raw_comment and ins_operands.jump.raw_func_start.
Since in loongarch_jump__parse(), these two fields are populated by
strchr()-ing the same buffer, trying to free them will lead to undefined
behavior.
This invalid free usually leads to crashes:
Process 1712902 (perf) of user 1000 dumped core.
Stack trace of thread 1712902:
#0 0x00007fffef155c58 n/a (libc.so.6 + 0x95c58)
#1 0x00007fffef0f7a94 raise (libc.so.6 + 0x37a94)
#2 0x00007fffef0dd6a8 abort (libc.so.6 + 0x1d6a8)
#3 0x00007fffef145490 n/a (libc.so.6 + 0x85490)
#4 0x00007fffef1646f4 n/a (libc.so.6 + 0xa46f4)
#5 0x00007fffef164718 n/a (libc.so.6 + 0xa4718)
#6 0x00005555583a6764 __zfree (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x106764)
#7 0x000055555854fb70 disasm_line__free (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x2afb70)
#8 0x000055555853d618 annotated_source__purge (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x29d618)
#9 0x000055555852300c __hist_entry__tui_annotate (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x28300c)
#10 0x0000555558526718 do_annotate (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x286718)
#11 0x000055555852ed94 evsel__hists_browse (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x28ed94)
#12 0x000055555831fdd0 cmd_report (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x7fdd0)
#13 0x000055555839b644 handle_internal_command (/home/csmantle/dist/linux-arch/tools/perf/perf + 0xfb644)
#14 0x00005555582fe6ac main (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x5e6ac)
#15 0x00007fffef0ddd90 n/a (libc.so.6 + 0x1dd90)
#16 0x00007fffef0ddf0c __libc_start_main (libc.so.6 + 0x1df0c)
#17 0x00005555582fed10 _start (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x5ed10)
ELF object binary architecture: LoongArch
... and it can be confirmed with Valgrind:
==1721834== Invalid free() / delete / delete[] / realloc()
==1721834== at 0x4EA9014: free (in /usr/lib/valgrind/vgpreload_memcheck-loongarch64-linux.so)
==1721834== by 0x4106287: __zfree (zalloc.c:13)
==1721834== by 0x42ADC8F: disasm_line__free (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x429B737: annotated_source__purge (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42811EB: __hist_entry__tui_annotate (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42848D7: do_annotate (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x428CF33: evsel__hists_browse (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== Address 0x7d34303 is 35 bytes inside a block of size 62 alloc'd
==1721834== at 0x4EA59B8: malloc (in /usr/lib/valgrind/vgpreload_memcheck-loongarch64-linux.so)
==1721834== by 0x6B80B6F: strdup (strdup.c:42)
==1721834== by 0x42AD917: disasm_line__new (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42AE5A3: symbol__disassemble_objdump (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42AF0A7: symbol__disassemble (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x429B3CF: symbol__annotate (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x429C233: symbol__annotate2 (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42804D3: __hist_entry__tui_annotate (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42848D7: do_annotate (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x428CF33: evsel__hists_browse (in /home/csmantle/dist/linux-arch/tools/perf/perf)
This patch adds the missing free() specialization in loongarch_jump_ops,
which prevents disasm_line__free() from invoking the default cleanup
function.
Fixes: fb7fd2a14a ("perf annotate: Move raw_comment and raw_func_start fields out of 'struct ins_operands'")
Cc: stable@vger.kernel.org
Cc: WANG Rui <wangrui@loongson.cn>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: loongarch@lists.linux.dev
Signed-off-by: Rong Bao <rong.bao@csmantle.top>
Tested-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Instead of using zalloc(nr_entries * sizeof_entry) that is what calloc()
does.
In some places where linux/zalloc.h isn't needed, remove it, add when
needed and was getting it indirectly.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
When a function call occurs, caller-saved registers are typically
invalidated since the callee may clobber them. However, DWARF debug info
provides location ranges that indicate exactly where a variable is valid
in a register.
Track the DWARF location range end address in type_state_reg and use it
to determine if a caller-saved register should be preserved across a
call. If the current call address is within the DWARF-specified lifetime
of the variable, keep the register state valid instead of invalidating
it.
This improves type annotation for code where the compiler knows a
register value survives across calls (e.g., when the callee is known not
to clobber certain registers or when the value is reloaded after the
call at the same logical location).
Changes:
- Add `end` and `has_range` fields to die_var_type to capture DWARF
location range information
- Add `lifetime_active` and `lifetime_end` fields to type_state_reg
- Check location lifetime before invalidating caller-saved registers
Signed-off-by: Zecheng Li <zli94@ncsu.edu>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Previously, the x86 call handler returned early without invalidating
caller-saved registers when the call target symbol could not be resolved
(func == NULL). This violated the ABI which requires caller-saved
registers to be considered clobbered after any call instruction.
Fix this by:
1. Always invalidating caller-saved registers for any call instruction
(except __fentry__ which preserves registers)
2. Using dl->ops.target.name as fallback when func->name is unavailable,
allowing return type lookup for more call targets
This is a conservative change that may reduce type coverage for indirect
calls (e.g., callq *(%rax)) where we cannot determine the return type
but it ensures correctness.
Signed-off-by: Zecheng Li <zli94@ncsu.edu>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add a helper function to consistently invalidate register state instead
of field assignments. This ensures kind, ok, and copied_from are all
properly cleared when a register becomes invalid.
The helper sets:
- kind = TSR_KIND_INVALID
- ok = false
- copied_from = -1
Replace all invalidation patterns with calls to this helper. No
functional change and this removes some incorrect annotations that were
caused by incomplete invalidation (e.g. a obsolete copied_from from an
invalidated register).
Signed-off-by: Zecheng Li <zli94@ncsu.edu>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>