Messages in this thread | | | Date | Fri, 20 Apr 2012 01:00:33 +0400 | From | Cyrill Gorcunov <> | Subject | Re: + c-r-prctl-add-ability-to-set-new-mm_struct-exe_file-update-after-mm- num_exe_file_vmas-removal.patch added to -mm tree |
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On Thu, Apr 19, 2012 at 09:20:05PM +0200, Oleg Nesterov wrote: > On 04/19, Andrew Morton wrote: > > > > From: Konstantin Khlebnikov <khlebnikov@openvz.org> > > Subject: c/r: prctl: update prctl_set_mm_exe_file() after mm->num_exe_file_vmas removal > > > > [ fix for "c-r-prctl-add-ability-to-set-new-mm_struct-exe_file-v2" from mm tree ] > > > > After removing mm->num_exe_file_vmas kernel keeps mm->exe_file until final > > mmput(), it never becomes NULL while task is alive. > > > > We can check for other mapped files in mm instead of checking > > mm->num_exe_file_vmas, and mark mm with flag MMF_EXE_FILE_CHANGED in order > > to forbid second changing of mm->exe_file. > > I lost the track a long ago. > > Just one question, what does this "forbid second changing" actually mean?
Heh :) Oleg, it was actually your idea to make this feature "one-shot". Once exe-file changed to a new value, it can't be changed again. The reason was to bring at least minimum disturbance in sysadmins life.
Cyrill
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