search for: msr_tsc

...he frigging PoS firmware people put on it. > > Ever since Nehalem TSC is stable (unless you get to >4 socket systems, > after which it still can be, but bets are off). But even relatively > recent systems fail the TSC sync test because firmware messes it up by > writing to either MSR_TSC or MSR_TSC_ADJUST. > > But the thing is, if the TSC is not synced, you cannot use it for > timekeeping, full stop. So having a single page is fine, it either > contains a mult/shift that is valid, or it indicates TSC is messed up > and you fall back to something else. > > The...

...he frigging PoS firmware people put on it. > > Ever since Nehalem TSC is stable (unless you get to >4 socket systems, > after which it still can be, but bets are off). But even relatively > recent systems fail the TSC sync test because firmware messes it up by > writing to either MSR_TSC or MSR_TSC_ADJUST. > > But the thing is, if the TSC is not synced, you cannot use it for > timekeeping, full stop. So having a single page is fine, it either > contains a mult/shift that is valid, or it indicates TSC is messed up > and you fall back to something else. > > The...

Marcelo Tosatti <mtosatti at redhat.com> writes: > On Wed, Oct 03, 2018 at 11:22:58AM +0200, Vitaly Kuznetsov wrote: >> >> There is a very long history of different (hardware) issues Marcelo was >> fighting with and the current code is the survived Frankenstein. > > Right, the code has to handle different TSC modes. > >> E.g. it >> is very, very

Marcelo Tosatti <mtosatti at redhat.com> writes: > On Wed, Oct 03, 2018 at 11:22:58AM +0200, Vitaly Kuznetsov wrote: >> >> There is a very long history of different (hardware) issues Marcelo was >> fighting with and the current code is the survived Frankenstein. > > Right, the code has to handle different TSC modes. > >> E.g. it >> is very, very

...y about (mostly), it is the frigging PoS firmware people put on it. Ever since Nehalem TSC is stable (unless you get to >4 socket systems, after which it still can be, but bets are off). But even relatively recent systems fail the TSC sync test because firmware messes it up by writing to either MSR_TSC or MSR_TSC_ADJUST. But the thing is, if the TSC is not synced, you cannot use it for timekeeping, full stop. So having a single page is fine, it either contains a mult/shift that is valid, or it indicates TSC is messed up and you fall back to something else. There is no inbetween there. For sche...

...people put on it. > > > > Ever since Nehalem TSC is stable (unless you get to >4 socket systems, > > after which it still can be, but bets are off). But even relatively > > recent systems fail the TSC sync test because firmware messes it up by > > writing to either MSR_TSC or MSR_TSC_ADJUST. > > > > But the thing is, if the TSC is not synced, you cannot use it for > > timekeeping, full stop. So having a single page is fine, it either > > contains a mult/shift that is valid, or it indicates TSC is messed up > > and you fall back to somet...

...t. >>> >>> Ever since Nehalem TSC is stable (unless you get to >4 socket systems, >>> after which it still can be, but bets are off). But even relatively >>> recent systems fail the TSC sync test because firmware messes it up by >>> writing to either MSR_TSC or MSR_TSC_ADJUST. >>> >>> But the thing is, if the TSC is not synced, you cannot use it for >>> timekeeping, full stop. So having a single page is fine, it either >>> contains a mult/shift that is valid, or it indicates TSC is messed up >>> and you fal...

...t. >>> >>> Ever since Nehalem TSC is stable (unless you get to >4 socket systems, >>> after which it still can be, but bets are off). But even relatively >>> recent systems fail the TSC sync test because firmware messes it up by >>> writing to either MSR_TSC or MSR_TSC_ADJUST. >>> >>> But the thing is, if the TSC is not synced, you cannot use it for >>> timekeeping, full stop. So having a single page is fine, it either >>> contains a mult/shift that is valid, or it indicates TSC is messed up >>> and you fal...