Valgrind considers the "cpuid" instruction to always depend on inputs from eax
and ecx, even though it's only a subset of values of eax for which ecx is
relevant. If ecx is undefined when cpuid is executed, the outputs of cpuid
will be considered undefined.
Instead of suppressing the resulting uninitialised-value warning (the
suppression for which is now out-of-date anyway, now that
register_all_protocols is moved to a worker thread), let's simply set ecx to
zero in ws_cpuid.
Testing done: Built Wireshark on Linux amd64. Before this change, running
"tools/valgrind-wireshark.sh ./test/captures/dhcp.pcap" with
valgrind-3.12.0.SVN on Debian 9.4 amd64 would yield the following Valgrind
error:
==2416== Thread 2:
==2416== Conditional jump or move depends on uninitialised value(s)
==2416== at 0xACB8B22: ws_mempbrk_sse42_compile (ws_mempbrk_sse42.c:58)
==2416== by 0x74F4960: register_all_protocols_worker (register.c:37)
==2416== by 0xB1403D4: g_thread_proxy (gthread.c:784)
==2416== by 0xD438493: start_thread (pthread_create.c:333)
==2416== by 0xB4CAACE: clone (clone.S:97)
With the change, the above message is gone. Inspected the disassembly of
function ws_cpuid, and it looks sane -- just an added "xor ecx, ecx" at the
top.
Change-Id: I2fb382309cac234c400286a6e9fac7d922912c63
Reviewed-on: https://code.wireshark.org/review/26733
Petri-Dish: Anders Broman <a.broman58@gmail.com>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>
The first is deprecated, as per https://spdx.org/licenses/.
Change-Id: I8e21e1d32d09b8b94b93a2dc9fbdde5ffeba6bed
Reviewed-on: https://code.wireshark.org/review/25661
Petri-Dish: Anders Broman <a.broman58@gmail.com>
Petri-Dish: Dario Lombardo <lomato@gmail.com>
Reviewed-by: Anders Broman <a.broman58@gmail.com>
Change-Id: Id73e641499e75bc1afc1dea29682418156f461fe
Reviewed-on: https://code.wireshark.org/review/24751
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot
Reviewed-by: Michael Mann <mmann78@netscape.net>
Otherwise _U_ is not defined.
Change-Id: I221f64c7d89c221e5a63a573e06457699d0a177e
Reviewed-on: https://code.wireshark.org/review/23440
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Michael Mann <mmann78@netscape.net>
Also give more details, for future reference, on how to determine
whether the processor supports CPUID.
Change-Id: I01e7173e45b0079f02338e51248238c05302dbd2
Reviewed-on: https://code.wireshark.org/review/6189
Reviewed-by: Guy Harris <guy@alum.mit.edu>
In case we make ws_cpuid() work on IA-32 processors, add a separate
"always returns no" version of ws_cpuid() for non-x86 processors.
Change-Id: Id6fbd3e5c7d4f04063bc9bcd8f1644cd617b297e
Reviewed-on: https://code.wireshark.org/review/6184
Reviewed-by: Guy Harris <guy@alum.mit.edu>
- Make ws_cpuid() return boolean when CPUID is support or no, this way
it's easier for caller to determinate if it works (and can use cpuinfo[X] or no).
- Add function ws_cpuid_sse42(), use it in ws_mempbrk() [cached] &
version information.
Change-Id: I4e77699f9f3d11bb9b2e8ea599e48d3c5ad84ed7
Reviewed-on: https://code.wireshark.org/review/2088
Reviewed-by: Anders Broman <a.broman58@gmail.com>
It'll be later used also for detecting sse4.2
Change-Id: I1930abb29026b455d453a79b5f301cdf37585160
Reviewed-on: https://code.wireshark.org/review/1803
Reviewed-by: Michael Mann <mmann78@netscape.net>
Роман Донченко