[MPlayer-users] [bug] segfault when tsc is disabled by the kernel

[D Richard Felker III]

On Sat, Nov 08, 2003 at 12:42:27AM +0100, Mathieu wrote:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> Hi,
> 
> I have a laptop running a linux kernel 2.4.22 on an intel pentium 4
> mobile. My kernel is configured with the Unsynced TSC support option
> ( CONFIG_X86_TSC_DISABLE ) and with notsc as a boot option. As a result, 
> TSC is disabled by the kernel though the processor could make it available.
> 
> The thing is that makes mplayer segfaults (current cvs or 1.0pre2) in
> GetCpuSpeed().
> 
> I replaced, in cpudetect.c : 
>     caps->hasTSC  = (regs2[3] & (1 << 4  )) >>  4; // 0x0000010
> by
>     caps->hasTSC = 0;
> and it works fine with that.
> 
> I don't know if it is possible to detect whether TSC has been disabled
> by the kernel but it would be nice to at least have a ./configure option
> --disable-tsc just like for mmx,mmx2,sse, ...

Is there a reason you _need_ to disable tsc? AFAIK this will seriously
hurt precise timing in all apps, including any movie player.

Rich