Re: exec and bzip2

[Samuel Thibault]

Roland McGrath, le Thu 02 Apr 2009 16:22:24 -0700, a écrit :
> > I am just wondering: why are faults a problem?  The bug I'm seeing seems
> > to happen when there is memory pressure and I guess gnumach trying to
> > drop pages.  But since exec doesn't seem to use its own pager, shouldn't
> > the usual page-in mechanism just work?  What makes exec particular?
> 
> These are file-mapped pages.  Faults are always possible, because the
> filesystem supplies the pagers and who knows what might happen.  In
> practice the disk filesystems' file pagers should never fail for read
> faults on valid file offsets unless there is a disk error or
> filesystem corruption, which they should probably be complaining about.

Ok, so maybe the issue was due to a bug that I've just fixed, whose
symptoms were completely different on another box: exec was unmapping
its own thread stacks, thus killing itself...  Here maybe the same bug
was just unmapping files.  Time will let me see what now happens.

Thanks,
Samuel