solaris - Spurious dtrace user stack traces? -

i using dtrace sample stack traces of process this:

# /usr/sbin/dtrace -p $mypid -x ustackframes=100 stack.d -s -o stack.log 

where stack.d looks like:

profile-99 /execname == "mybinary"/ {     @[execname, ustack()] = count(); } 

i adding -p dtrace such has symbols during stack writing when user process has exited.

this works - observe 3 issues:

during tracing regularly error messages like:

dtrace: error on enabled probe id 1 (id 12345: profile:::profile-99):\   invalid address (0x0) in action #3 dtrace: error on enabled probe id 1 (id 12345: profile:::profile-99):\   invalid address (0xffffffff00000000) in action #3 dtrace: error on enabled probe id 1 (id 12345: profile:::profile-99):\   invalid address (0x7ffe8000) in action #3 [..] 

(i.e. many of those)

what underlying issue there?

the process executes should (i.e. no crashes).

the other thing lot of recorded stacks don't contain symbols @ all.

what possible reasons such symbol-less stacks?

also - stacks not start _start -> main still contain symbols (i.e. function binary).

are incomplete stacks ones dtrace somehow failed bottom?