hi Sudeep： Thanks for your email. Ok, I'll check it out. -- Regards, Aaron. On Mon, May 11, 2020 at 4:18 PM Sudeep Holla <sudeep.holla@xxxxxxx> wrote: > > On Mon, May 11, 2020 at 03:30:51PM +0800, Aaron Chou wrote: > > In the system, I can get the L3 cache size from two or more ways. > > > > Which platform is this ? More details would help. > > > Firstly, I can get it from the kernel interface, such as the `lscpu` command. > > Also, I can cat the file `/sys/devices/system/cpu/cpu3/cache/index3/size`. > > > > IIRC, lscpu parse the above mentioned sysfs files and the above result > match the expectation. > > > The way above can give me the L3 cache size is 32768K. > > > > OK > > > Now if I use the `dmidecode -t cache` command, I get the L3 cache size > > is 24576K. > > > > Ah, that's bad. > > > And the real size of the L3 cache is 24576K. > > > > OK > > > Why is it? who can explain it to me? > > > > ACPI reads these cache information from PPTT. The firmware which populates > the ACPI PPTT must read it from DMI entries and keep them in sync. On > this system, looks like the firmware tried to be more imaginative and > populated PPTT with wrong values. Get that firmware fixed please! > > -- > Regards, > Sudeep
