This reverts commit e4b980c853.
When a binary links against a .a archive (as opposed to a shared library),
any symbols which are marked as 'weak' get silently dropped. As a result
when the binary later runs, those 'weak' functions have an address of
0x0 and thus crash when run.
This happened with virtlogd and virtlockd because they don't link to
libvirt.so, but instead just libvirt_util.a and libvirt_rpc.a. The
virRandomBits symbols was weak and so left out of the virtlogd &
virtlockd binaries, despite being required by virHashTable functions.
Various other binaries like libvirt_lxc, libvirt_iohelper, etc also
link directly to .a files instead of libvirt.so, so are potentially
at risk of dropping symbols leading to a later runtime crash.
This is normal linker behaviour because a weak symbol is not treated
as undefined, so nothing forces it to be pulled in from the .a You
have to force the linker to pull in weak symbols using -u$SYMNAME
which is not a practical approach.
This risk is silent bad linkage that affects runtime behaviour is
not acceptable for a fix that was merely trying to fix the test
suite. So stop using __weak__ again.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently all mockable functions are annotated with the 'noinline'
attribute. This is insufficient to guarantee that a function can
be reliably mocked with an LD_PRELOAD. The C language spec allows
the compiler to assume there is only a single implementation of
each function. It can thus do things like propagating constant
return values into the caller at compile time, or creating
multiple specialized copies of the function body each optimized
for a different caller. To prevent these optimizations we must
also set the 'noclone' and 'weak' attributes.
This fixes the test suite when libvirt.so is built with CLang
with optimization enabled.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
CLang's optimizer is more aggressive at inlining functions than
gcc and so will often inline functions that our tests want to
mock-override. This causes the test to fail in bizarre ways.
We don't want to disable inlining completely, but we must at
least prevent inlining of mocked functions. Fortunately there
is a 'noinline' attribute that lets us control this per function.
A syntax check rule is added that parses tests/*mock.c to extract
the list of functions that are mocked (restricted to names starting
with 'vir' prefix). It then checks that src/*.h header file to
ensure it has a 'ATTRIBUTE_NOINLINE' annotation. This should prevent
use from bit-rotting in future.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When enabling IPv6 on all interfaces, we may get the host Router
Advertisement routes discarded. To avoid this, the user needs to set
accept_ra to 2 for the interfaces with such routes.
See https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt
on this topic.
To avoid user mistakenly losing routes on their hosts, check
accept_ra values before enabling IPv6 forwarding. If a RA route is
detected, but neither the corresponding device nor global accept_ra
is set to 2, the network will fail to start.
Proposed formal coding conventions encourage defining typedefs for
vir[Blah] and vir[Blah]Ptr separately from the associated struct named
_vir[Blah]:
typedef struct _virBlah virBlah;
typedef virBlah *virBlahPtr;
struct _virBlah {
...
};
At some point in the past, I had submitted several patches using a
more compact style that I prefer, and they were accepted:
typedef struct _virBlah {
...
} virBlah, *virBlahPtr;
Since these are by far a minority among all struct definitions, this
patch changes all those definitions to reflect the style prefered by
the proposal so that there is 100% consistency.
The peer attribute is used to set the property of the same name in the
interface IP info:
<interface type='ethernet'>
...
<ip family='ipv4' address='192.168.122.5'
prefix='32' peer='192.168.122.6'/>
...
</interface>
Note that this element is used to set the IP information on the
*guest* side interface, not the host side interface - that will be
supported in an upcoming patch.
(This patch now has quite a history: it was originally pushed in
commit 690969af, which was subsequently reverted in commit 1d14b13f,
then reworked and pushed (along with a lot of other related/supporting
patches) in commit 93135abf1; however *that* commit had been
accidentally pushed during dev. freeze for release 2.0.0, so it was
again reverted in commit f6acf039f0).
Signed-off-by: Vasiliy Tolstov <v.tolstov@selfip.ru>
Signed-off-by: Laine Stump <laine@laine.org>
This patch takes the code out of
lxcContainerRenameAndEnableInterfaces() that adds all IP addresses and
IP routes to the interface, and puts it into a utility function
virNetDevIPInfoAddToDev() in virnetdevip.c so that it can be used by
anyone.
One small change in functionality -
lxcContainerRenameAndEnableInterfaces() previously would add all IP
addresses to the interface while it was still offline, then set the
interface online, and then add the routes. Because I don't want the
utility function to set the interface online, I've moved this up so
the interface is first set online, then IP addresses and routes are
added. This is the same order that the network service from
initscripts (in ifup-ether) does it, so it shouldn't pose any problem
(and hasn't, in the tests that I've run).
(This patch had been pushed earlier in commit
f1e0d0da11, but was reverted in commit
05eab47559 because it had been
accidentally pushed during the freeze for release 2.0.0)
The peer attribute is used to set the property of the same name in the
interface IP info:
<interface type='ethernet'>
...
<ip family='ipv4' address='192.168.122.5'
prefix='32' peer='192.168.122.6'/>
...
</interface>
Note that this element is used to set the IP information on the
*guest* side interface, not the host side interface - that will be
supported in an upcoming patch.
(This is an updated *re*-commit of commit 690969af, which was
subsequently reverted in commit 1d14b13f).
Signed-off-by: Vasiliy Tolstov <v.tolstov@selfip.ru>
Signed-off-by: Laine Stump <laine@laine.org>
This patch takes the code out of
lxcContainerRenameAndEnableInterfaces() that adds all IP addresses and
IP routes to the interface, and puts it into a utility function
virNetDevIPInfoAddToDev() in virnetdevip.c so that it can be used by
anyone.
One small change in functionality -
lxcContainerRenameAndEnableInterfaces() previously would add all IP
addresses to the interface while it was still offline, then set the
interface online, and then add the routes. Because I don't want the
utility function to set the interface online, I've moved this up so
the interface is first set online, then IP addresses and routes are
added. This is the same order that the network service from
initscripts (in ifup-ether) does it, so it shouldn't pose any problem
(and hasn't, in the tests that I've run).
There are currently two places in the domain where this combination is
used, and there is about to be another. This patch puts them together
for brevity and uniformity.
As with the newly-renamed virNetDevIPAddr and virNetDevIPRoute
objects, the new virNetDevIPInfo object will need to be accessed by a
utility function that calls low level Netlink functions (so we don't
want it to be in the conf directory) and will be called from multiple
hypervisor drivers (so it can't be in any hypervisor directory); the
most appropriate place is thus once again the util directory.
The parse and format functions are in conf/domain_conf.c because only
the domain XML (i.e. *not* the network XML) has this exact combination
of IP addresses plus routes. Note that virDomainNetIPInfoFormat() will
end up being the only caller to virDomainNetRoutesFormat() and
virDomainNetIPsFormat(), so it will just subsume those functions in a
later patch, but we can't do that until they are no longer called.
(It would have been nice to include the interface name within the
virNetDevIPInfo object (with a slight name change), but that can't
be done cleanly, because in each case the interface name is provided
in a different place in the XML relative to the routes and IP
addresses, so putting it in this object would actually make the code
more confused rather than simpler).
These functions all need to be called from a utility function that
must be located in the util directory, so we move them all into
util/virnetdevip.[ch] now that it exists.
Function and struct names were appropriately changed for the new
location, but all code is unchanged aside from motion and renaming.
This patch splits virnetdev.[ch] into multiple files, with the new
virnetdevip.[ch] containing all the functions related to setting and
retrieving IP-related info for a device (both addresses and routes).
