Displaying 6 results from an estimated 6 matches for "hlt_logical_cpus".
2009 Feb 22
2
The machdep.hyperthreading_allowed & ULE weirdness in 7.1
...I>
FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs
cpu0 (BSP): APIC ID: 0
cpu1 (AP): APIC ID: 1
ioapic0: Changing APIC ID to 2
ioapic0 <Version 2.0> irqs 0-23 on motherboard
ioapic1 <Version 2.0> irqs 24-47 on motherboard
machdep.cpu_idle_hlt: 1
machdep.hlt_cpus: 0
machdep.hlt_logical_cpus: 0
machdep.logical_cpus_mask: 2
If I flip machdep.hyperthreading_allowed sysctl, I still can see
processes scheduled to both logical CPUs, yet, if I check IRQ status in
the systat -vm, the CPU1 is not getting any timer interrupts, while CPU0
gets twice the normal amount. I wonder if something i...
2005 May 12
0
FreeBSD Security Advisory FreeBSD-SA-05:09.htt
...Information may be disclosed to local users, allowing in many cases for
privilege escalation.
IV. Workaround
Systems not using processors with Hyper-Threading support are not
affected by this issue. On systems which are affected, the security
flaw can be eliminated by setting the "machdep.hlt_logical_cpus"
tunable:
# echo "machdep.hlt_logical_cpus=1" >> /boot/loader.conf
The system must be rebooted in order for tunables to take effect.
Use of this workaround is not recommended on "dual-core" systems, as
this workaround will also disable one of the processor cores....
2005 May 12
0
FreeBSD Security Advisory FreeBSD-SA-05:09.htt
...Information may be disclosed to local users, allowing in many cases for
privilege escalation.
IV. Workaround
Systems not using processors with Hyper-Threading support are not
affected by this issue. On systems which are affected, the security
flaw can be eliminated by setting the "machdep.hlt_logical_cpus"
tunable:
# echo "machdep.hlt_logical_cpus=1" >> /boot/loader.conf
The system must be rebooted in order for tunables to take effect.
Use of this workaround is not recommended on "dual-core" systems, as
this workaround will also disable one of the processor cores....
2005 May 13
0
FreeBSD Security Advisory FreeBSD-SA-05:09.htt [REVISED]
...cryptographic keys used in applications such as OpenSSH
or SSL-enabled web servers.
IV. Workaround
Systems not using processors with Hyper-Threading Technology support are
not affected by this issue. On systems which are affected, the security
flaw can be eliminated by setting the "machdep.hlt_logical_cpus" tunable:
# echo "machdep.hlt_logical_cpus=1" >> /boot/loader.conf
The system must be rebooted in order for tunables to take effect.
Use of this workaround is not recommended on "dual-core" systems, as
this workaround will also disable one of the processor cores....
2005 May 13
1
FreeBSD Security Advisory FreeBSD-SA-05:09.htt [REVISED]
...cryptographic keys used in applications such as OpenSSH
or SSL-enabled web servers.
IV. Workaround
Systems not using processors with Hyper-Threading Technology support are
not affected by this issue. On systems which are affected, the security
flaw can be eliminated by setting the "machdep.hlt_logical_cpus" tunable:
# echo "machdep.hlt_logical_cpus=1" >> /boot/loader.conf
The system must be rebooted in order for tunables to take effect.
Use of this workaround is not recommended on "dual-core" systems, as
this workaround will also disable one of the processor cores....
2003 Nov 01
1
CPU1 never used despite HTT?
Hi,
I am running a Xeon with hyperthreading support. Until last week's HTT
modifications, according to ps(1) and top(1) both logicals CPUs were in
use. (Processes in CPU0 and CPU1 state; "C" column showing "0" or "1".)
This has changed with a recent -STABLE kernel which includes last week's
changes to HTT (removing "options HTT"). I am only seeing