Date: Sun, 24 Sep 2023 10:26:21 +0000 From: bugzilla-noreply@freebsd.org To: ports-bugs@FreeBSD.org Subject: [Bug 273688] sysutils/pstack: does not work with Valgrind Message-ID: <bug-273688-7788-dbyAv9ZRRn@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-273688-7788@https.bugs.freebsd.org/bugzilla/> References: <bug-273688-7788@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D273688 --- Comment #2 from Paul Floyd <pjfloyd@wanadoo.fr> --- Some more analysis In first window,=20 ./vg-in-place sleep 100000 Tthat's my dev build of Valgrind, just 'valgrind' from pkd devel/valgrind-d= evel should be fine as well. In the second window, GDB test (gdb) attach 48907 Attaching to process 48907 Reading symbols from /usr/home/paulf/scratch/valgrind/memcheck/memcheck-amd64-freebsd... [Switching to LWP 104670 of process 48907] vgModuleLocal_do_syscall_for_client_WRK () at m_syswrap/syscall-amd64-freebsd.S:144 144 setc 0(%rsp) /* stash returned carry flag */ (gdb) bt #0 vgModuleLocal_do_syscall_for_client_WRK () at m_syswrap/syscall-amd64-freebsd.S:144 #1 0x000000003819f27a in do_syscall_for_client (syscallno=3D240, tst=3D0x1002024f10, syscall_mask=3D0x1002ca9e20) at m_syswrap/syswrap-main.= c:368 #2 vgPlain_client_syscall (tid=3Dtid@entry=3D1, trc=3Dtrc@entry=3D73) at m_syswrap/syswrap-main.c:2341 #3 0x000000003819b150 in handle_syscall (tid=3Dtid@entry=3D1, trc=3Dtrc@en= try=3D73) at m_scheduler/scheduler.c:1206 #4 0x0000000038199223 in vgPlain_scheduler (tid=3Dtid@entry=3D1) at m_scheduler/scheduler.c:1552 #5 0x00000000381ab33c in thread_wrapper (tidW=3D1) at m_syswrap/syswrap-freebsd.c:112 #6 run_a_thread_NORETURN (tidW=3D1) at m_syswrap/syswrap-freebsd.c:166 #7 0x0000000000000000 in ?? () That's what I'd expect. And lldb: (lldb) attach 48907 This version of LLDB has no plugin for the language "assembler". Inspection= of frame variables will be limited. Process 48907 stopped * thread #1, name =3D 'memcheck-amd64-f', stop reason =3D signal SIGSTOP frame #0: 0x00000000381a03a6 memcheck-amd64-freebsd`vgModuleLocal_do_syscall_for_client_WRK at syscall-amd64-freebsd.S:144 141 but hasn't been committed to RAX. */ 142=20 143 /* stack contents: 3 words for syscall above, plus our prologue = */ -> 144 setc 0(%rsp) /* stash returned carry flag */ 145=20 146 movq -16(%rbp), %r11 /* r11 =3D VexGuestAMD64State * */ 147 movq %rax, OFFSET_amd64_RAX(%r11) /* save back to RAX */ Executable module set to "/usr/home/paulf/scratch/valgrind/memcheck/memcheck-amd64-freebsd". Architecture set to: x86_64-unknown-freebsd13.2. (lldb) bt * thread #1, name =3D 'memcheck-amd64-f', stop reason =3D signal SIGSTOP * frame #0: 0x00000000381a03a6 memcheck-amd64-freebsd`vgModuleLocal_do_syscall_for_client_WRK at syscall-amd64-freebsd.S:144 frame #1: 0x000000003819f27a memcheck-amd64-freebsd`vgPlain_client_sysc= all [inlined] do_syscall_for_client(syscallno=3D240, tst=3D0x0000001002024f10, syscall_mask=3D0x0000001002ca9e20) at syswrap-main.c:368:10 frame #2: 0x000000003819f232 memcheck-amd64-freebsd`vgPlain_client_syscall(tid=3D1, trc=3D73) at syswrap-main.c:2341:10 frame #3: 0x000000003819b150 memcheck-amd64-freebsd`handle_syscall(tid= =3D1, trc=3D73) at scheduler.c:1206:4 frame #4: 0x0000000038199223 memcheck-amd64-freebsd`vgPlain_scheduler(tid=3D1) at scheduler.c:1552:3 frame #5: 0x00000000381ab33c memcheck-amd64-freebsd`run_a_thread_NORETU= RN [inlined] thread_wrapper(tidW=3D1) at syswrap-freebsd.c:112:10 frame #6: 0x00000000381ab2c6 memcheck-amd64-freebsd`run_a_thread_NORETURN(tidW=3D1) at syswrap-freebsd.c:166:10 Again, that's OK. I've dowloaded the pstack source from github and built it. In gdb, looking at elfFindSymbolByAddress I see that the address that pstac= k is using is the same as the address I see when attaching gdb. Namely 0x381a03a= 6. There is no .dynsym so elfFindSectionByName finds .symtab. symStrings looks OK to me. The frst entry is nil, and after that there is (gdb) x /s obj->fileData + shdrs[symSection->sh_link]->sh_offset+1 0x8027e5829: "mc_leakcheck.c" That matches what I see with objdump -t: paulf> objdump -t /usr/home/paulf/scratch/valgrind/memcheck/memcheck-amd64-freebsd | less=20= =20=20=20=20=20=20=20=20 /usr/home/paulf/scratch/valgrind/memcheck/memcheck-amd64-freebsd: file format elf64-x86-64-freebsd SYMBOL TABLE: 0000000000000000 l df *ABS* 0000000000000000 mc_leakcheck.c And the function where it is sleeping is 00000000381a034c g .text 0000000000000000 vgModuleLocal_do_syscall_for_client_WRK I've done some more debugging and I've seen one error. @ -196,11 +198,23 @@ elfFindSymbolByAddress(struct ElfObject *obj, Elf_Addr addr, symSection->sh_offset + symSection->sh_size); for (; sym < endSym; sym++) { - if ((type =3D=3D STT_NOTYPE || + if ((ELF_ST_TYPE(sym->st_info) =3D=3D STT_NOTYPE || elfFindSymbolByAddress is only ever called with type =3D=3D STT_FUNC and so STT_FUNC =3D=3D STT_NOTYPE is always false and any function with type STT_NOTYPE aren't processed. I suppose STT_NOTYPE also means a size of 0. With the above change I get 0x381a03a6 vgModuleLocal_do_syscall_for_client_WRK (3819f27a, 0, 1301, 0, 3812ddf8, 0) + 5a but only the one line. I need to so some more debugging of elfFindSymbolByAddress() to see why it's not getting the full callstack. --=20 You are receiving this mail because: You are the assignee for the bug.=
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