for the mapping by the object' file with the protection and mode of
the first loadable segment over the whole region. Then, it maps other
segments at the appropriate addresses inside the region.
On amd64, due to default alignment of the segments being 1Gb, the
subsequent segment mappings leave the holes in the region, that usually
contain mapping of the object' file past eof. Such mappings prevent
wiring of the address space, because the pages cannot be faulted in.
Change the way the mapping of the ELF objects is constructed, by first
mapping PROT_NONE anonymous memory over the whole range, and then
mapping the segments of the object over it. Take advantage of this new
order and allocate .bss by changing the protection of the range instead
of remapping.
Note that we cannot simply keep the holes between segments, because
other mappings may be made there. Among other issues, when the dso is
unloaded, rtld unmaps the whole region, deleting unrelated mappings.
The kernel ELF image activator does put the holes between segments, but
this is not critical for now because kernel loads only executable image
and interpreter, both cannot be unloaded. This will be fixed later, if
needed.
Reported and tested by: Hans Ottevanger <fbsdhackers beasties demon nl>
Suggested and reviewed by: kan, alc
types of MAC overheads such as preambles, link level retransmissions
and more.
Note- this commit changes the userland/kernel ABI for pipes
(but not for ordinary firewall rules) so you need to rebuild
kernel and /sbin/ipfw to use dummynet features.
Please check the manpage for details on the new feature.
The MFC would be trivial but it breaks the ABI, so it will
be postponed until after 7.2 is released.
Interested users are welcome to apply the patch manually
to their RELENG_7 tree.
Work supported by the European Commission, Projects Onelab and
Onelab2 (contract 224263).
We typically wire translation to devices with TLB1 entries and
pmap_kextract() does not know about those and returns 0. This
causes false positives (read: all serial ports suddenly become
the console).
Do not use Giant for kbdmux(4) locking. This is wrong and apparently
causing more problems than it solves. This will re-open the issue
where interrupt handlers may race with kbdmux(4) in polling mode.
Typical symptoms include (but not limited to) duplicated and/or
missing characters when low level console functions (such as gets)
are used while interrupts are enabled (for example geli password
prompt, mountroot prompt etc.)
MFC after: 3 days
Most compilers nowadays (including GCC) are smart enough to know what's
going on and generate more efficient code anyway.
Submitted by: Christoph Mallon <christoph.mallon@gmx.de>
It turns out my handling of SIGTTOU and SIGTTIN didn't entirely comply
to the standards. It is true that in the SIGTTOU case we should not
return EIO when the signal is ignored/blocked, but in the SIGTTIN case
we must.
See also: POSIX issue 7 section 11.1.4
above to avoid referencing undefined terms (humans are not compilers
but still care about these things).
Change some .Sh to .Ss to better reflect the structure of the text.
No new content.
(framing, parity, etc), but does not indicate characters
being received. Since no chracters have been received,
ignore the line errors.
PR: 131006
MFC after: 3 days
the size and cost of name cache entries, but make adding debugging
and tracing easier.
Add SDT DTrace probes for various namecache events:
vfs:namecache:enter:done - new entry in the name cache, passed parent
directory vnode pointer, name added to the cache, and child vnode
pointer.
vfs:namecache:enter_negative:done - new negative entry in the name cache,
passed parent vnode pointer, name added to the cache.
vfs:namecache:fullpath:enter - call to vn_fullpath1() is made, passed
the vnode to resolve to a name.
vfs:namecache:fullpath:hit - vn_fullpath1() successfully resolved a
search for the parent of an object using the namecache, passed the
discovered parent directory vnode pointer, name, and child vnode
pointer.
vfs:namecache:fullpath:miss - vn_fullpath1() failed to resolve a search
for the parent of an object using the namecache, passed the child
vnode pointer.
vfs:namecache:fullpath:return - vn_fullpath1() has completed, passed the
error number, and if that is zero, the vnode to resolve, and the
returned path.
vfs:namecache:lookup:hit - postive name cache entry hit, passed the
parent directory vnode pointer, name, and child vnode pointer.
vfs:namecache:lookup:hit_negative - negative name cache entry hit,
passed the parent directory vnode pointer and name.
vfs:namecache:lookup:miss - name cache miss, passed the parent directory
pointer and the full remaining component name (not terminated after the
cache miss component).
vfs:namecache:purge:done - name cache purge for a vnode, passed the vnode
pointer to purge.
vfs:namecache:purge_negative:done - name cache purge of negative entries
for children of a vnode, passed the vnode pointer to purge.
vfs:namecache:purgevfs - name cache purge for a mountpoint, passed the
mount pointer. Separate probes will also be invoked for each cache
entry zapped.
vfs:namecache:zap:done - name cache entry zapped, passed the parent
directory vnode pointer, name, and child vnode pointer.
vfs:namecache:zap_negative:done - negative name cache entry zapped,
passed the parent directory vnode pointer and name.
For any probes involving an extant name cache entry (enter, hit, zapp),
we use the nul-terminated string for the name component. For misses,
the remainder of the path, including later components, is provided as
an argument instead since there is no handy nul-terminated version of
the string around. This is arguably a bug.
MFC after: 1 month
Sponsored by: Google, Inc.
Reviewed by: jhb, kan, kib (earlier version)
