forked from Minki/linux
mainlining shenanigans
d3878e164d
The TSC calibration code uses HPET as reference. The conversion normalizes the delta of two HPET timestamps: hpetref = ((tshpet1 - tshpet2) * HPET_PERIOD) / 1e6 and then divides the normalized delta of the corresponding TSC timestamps by the result to calulate the TSC frequency. tscfreq = ((tstsc1 - tstsc2 ) * 1e6) / hpetref This uses do_div() which takes an u32 as the divisor, which worked so far because the HPET frequency was low enough that 'hpetref' never exceeded 32bit. On Skylake machines the HPET frequency increased so 'hpetref' can exceed 32bit. do_div() truncates the divisor, which causes the calibration to fail. Use div64_u64() to avoid the problem. [ tglx: Fixes whitespace mangled patch and rewrote changelog ] Signed-off-by: Xiaoming Gao <newtongao@tencent.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Cc: peterz@infradead.org Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/38894564-4fc9-b8ec-353f-de702839e44e@gmail.com |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.