[Bug runtime/10848] New: enforcement of memory limits

[Bug runtime/10848] New: enforcement of memory limits

[fche at redhat dot com]

It would be useful for a sysadmin to assert that a stap module
(especially in unprivileged mode) not be allowed to consume more
than some give MB of memory.

This sort of thing could involve:

- checking the .ko file at -p4 or -p5 time for ELF stats about .text/.data/.bss
  sizes, and comparing them to limits
- perhaps teaching staprun to "create" free kernel memory (such as by creating
  a short-lived process that touches/consumes enough memory, then killing it
  just before the module_insert)
- extending the _stp_*alloc functions to prematurely reject requests if limits
  are about to be exceeded
- checking that every other use of kernel allocations go through _stp_alloc*
- checking that all kernel-side memory allocations use __GFP_NORETRY or such
  to preclude triggering OOM handling elsewhere

-- 
           Summary: enforcement of memory limits
           Product: systemtap
           Version: unspecified
            Status: NEW
          Severity: normal
          Priority: P2
         Component: runtime
        AssignedTo: systemtap at sources dot redhat dot com
        ReportedBy: fche at redhat dot com


http://sourceware.org/bugzilla/show_bug.cgi?id=10848

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[Bug runtime/10848] enforcement of memory limits

[fche at redhat dot com]

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http://sourceware.org/bugzilla/show_bug.cgi?id=10848

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[Bug runtime/10848] enforcement of memory limits

[dsmith at redhat dot com]

------- Additional Comments From dsmith at redhat dot com  2009-12-09 16:42 -------
(In reply to comment #0)
> - checking that every other use of kernel allocations go through _stp_alloc*
> - checking that all kernel-side memory allocations use __GFP_NORETRY or such
>   to preclude triggering OOM handling elsewhere

Commit 965b658 makes sure all kernel-side memory allocations go through the
_stp_alloc* functions (except for uprobes).  The _stp_alloc* functions already
used __GFP_NOTRETRY everywhere.

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           What    |Removed                     |Added
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         AssignedTo|systemtap at sources dot    |dsmith at redhat dot com
                   |redhat dot com              |
             Status|NEW                         |ASSIGNED


http://sourceware.org/bugzilla/show_bug.cgi?id=10848

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