systemtap-1.4-3.fc15.x86_64 I have the glibc with sdt probes installed, you can get it from http://koji.fedoraproject.org/scratch/roland/task_2877130/ (though that may expire in a few days). Both glibc.x86_64 and glibc.i686 rpms from there are installed. I used this script: probe process("/lib*/libc.so.*").mark("*jmp*") { printf("%s(%p, %d) from PC %p: %s\n", $$name, $arg1, $arg2, $arg3, sprint_ubacktrace()); } That was in -e, along with -d .../setjmp --ldd where .../setjmp is an i686 executable (and -c .../setjmp was at the end). This produced: WARNING: Downgrading SDT_V2 probe argument to dwarf, can't parse '4+4(%esp)': identifier '$arg2' at <input>:1:103 That argument appears in /lib/libc.so.6, which is the i686 DSO. 1. It says SDT_V2 when in fact this is v3. 2. I don't understand what "downgrading to dwarf" means anyway, since DWARF is of no help at all for the $arg2 syntax and what appears to happen is that the instance of the sdt probe that uses the problematic syntax just doesn't actually get probed at all. 3. The problem appears to be the 4+4 in the operand syntax. Having simple arithmetic expressions in the displacements in operands, or in constant operands, is common in hand-written assembly (usually resulting from cpp macros used in the assembly, in fact). 4. The same error occurs when .../setjmp is an x86-64 executable instead, in which case the script actually works as intended because /lib/libc.so.6 is never used in the x86-64 process, and the probes in /lib64/libc.so.6 work fine.
(In reply to comment #0) > probe process("/lib*/libc.so.*").mark("*jmp*") { printf("%s(%p, %d) from PC %p: > That was in -e, along with -d .../setjmp --ldd where .../setjmp is an i686 > executable (and -c .../setjmp was at the end). (The -d / --ldd part should not be necessary.) > This produced: > WARNING: Downgrading SDT_V2 probe argument to dwarf, can't parse '4+4(%esp)': > identifier '$arg2' at <input>:1:103 > > That argument appears in /lib/libc.so.6, which is the i686 DSO. > 1. It says SDT_V2 when in fact this is v3. OK, a misnomer. > 2. I don't understand what "downgrading to dwarf" means anyway, since DWARF is > of no help at all for the $arg2 syntax and what appears to happen is that the > instance of the sdt probe that uses the problematic syntax just doesn't > actually get probed at all. For a C/C++ program with SDT_V2, if unexpected operand strings appear in the .notes, stap does attempt to use DWARF to get at the (former) temporary copies of the parameters. In SDT_V3, there is no such temporary, so there won't be a DWARF record by those names anyway, so we cannot fall back. > 3. The problem appears to be the 4+4 in the operand syntax. Having simple > arithmetic expressions in the displacements in operands, or in constant > operands, is common in hand-written assembly (usually resulting from cpp macros > used in the assembly, in fact). We should support some reasonable subset of such expressions. > 4. The same error occurs when .../setjmp is an x86-64 executable instead, in > which case the script actually works as intended because /lib/libc.so.6 is > never used in the x86-64 process, and the probes in /lib64/libc.so.6 work fine. Odd.
commit: e5b7b83f42 Allow offset to be +-N+-N+-N