cvs commit: src/share/man/man4 Makefile cpuctl.4 src/sys/amd64/amd64 support.S src/sys/amd64/conf NOTES src/sys/amd64/include cpufunc.h specialreg.h src/sys/conf files.amd64 files.i386 src/sys/dev/cpuctl cpuctl.c ...

[Kostik Belousov]

On Fri, Aug 08, 2008 at 12:51:17PM -0400, John Baldwin wrote:
> On Friday 08 August 2008 12:26:53 pm Stanislav Sedov wrote:
> > stas        2008-08-08 16:26:53 UTC
> > 
> >   FreeBSD src repository
> > 
> >   Modified files:
> >     share/man/man4       Makefile 
> >     sys/amd64/amd64      support.S 
> >     sys/amd64/conf       NOTES 
> >     sys/amd64/include    cpufunc.h specialreg.h 
> >     sys/conf             files.amd64 files.i386 
> >     sys/i386/conf        NOTES 
> >     sys/i386/i386        support.s 
> >     sys/i386/include     cpufunc.h specialreg.h 
> >     sys/modules          Makefile 
> >     sys/sys              priv.h 
> >     usr.sbin             Makefile 
> >   Added files:
> >     share/man/man4       cpuctl.4 
> >     sys/dev/cpuctl       cpuctl.c 
> >     sys/modules/cpuctl   Makefile 
> >     sys/sys              cpuctl.h 
> >     usr.sbin/cpucontrol  Makefile amd.c amd.h cpucontrol.8 
> >                          cpucontrol.c cpucontrol.h intel.c intel.h 
> >   Log:
> >   SVN rev 181430 on 2008-08-08 16:26:53Z by stas
> >   
> >   - Add cpuctl(4) pseudo-device driver to provide access to some low-level
> >     features of CPUs like reading/writing machine-specific registers,
> >     retrieving cpuid data, and updating microcode.
> >   - Add cpucontrol(8) utility, that provides userland access to
> >     the features of cpuctl(4).
> >   - Add subsequent manpages.
> >   
> >   The cpuctl(4) device operates as follows. The pseudo-device node cpuctlX
> >   is created for each cpu present in the systems. The pseudo-device minor
> >   number corresponds to the cpu number in the system. The cpuctl(4) pseudo-
> >   device allows a number of ioctl to be preformed, namely RDMSR/WRMSR/CPUID
> >   and UPDATE. The first pair alows the caller to read/write machine-specific
> >   registers from the correspondent CPU. cpuid data could be retrieved using
> >   the CPUID call, and microcode updates are applied via UPDATE.
> >   
> >   The permissions are inforced based on the pseudo-device file permissions.
> >   RDMSR/CPUID will be allowed when the caller has read access to the device
> >   node, while WRMSR/UPDATE will be granted only when the node is opened
> >   for writing. There're also a number of priv(9) checks.
> >   
> >   The cpucontrol(8) utility is intened to provide userland access to
> >   the cpuctl(4) device features. The utility also allows one to apply
> >   cpu microcode updates.
> >   
> >   Currently only Intel and AMD cpus are supported and were tested.
> 
> Note that cpuid isn't a privileged instruction, so I'm not sure it's really 
> worth having an ioctl for that particular case.

It was discussed when patch was reviewed on current at . The ioctl allows
to get cpuid information for specific processor, as opposed to some
random core curthread happens to run ATM.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 195 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/cvs-src/attachments/20080808/8eaee967/attachment.pgp