On Fri, 6 May 2016, Thomas Gleixner wrote: > On Fri, 6 May 2016, yu.c.c...@intel.com wrote: > > From: Chen Yu <yu.c.c...@intel.com> > > > > Currently we fetch the tsc radio by: > > ratio = (lo >> 8) & 0x1f; > > thus get bit8~bit12 of the MSR_PLATFORM_INFO, however according > > to Intel 64 and IA-32 Architectures Software Developer Manual 35.5, > > the ratio bit should be bit8~bit15, otherwise we might get incorrect > > tsc ratio and cause system hang later(mdelay corrupted). > > The resulting issue is that both TSC frequency, which is used for udelay, and > the lapic timer frequency are wrong. mdelay is just the visible damage caused > by that.
Aside of that: > Cc: 3.14+ <sta...@vger.kernel.org> # 3.14+ Please use: Fixes: commit '....' next time, which identifies the kernel version to which this needs to be backported and gives a reference to the commit which caused the issue. Thanks, tglx