Messages in this thread | | | From | "Ghannam, Yazen" <> | Subject | RE: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA MCA_DE{STAT,ADDR} registers | Date | Wed, 5 Apr 2017 17:53:57 +0000 |
| |
> -----Original Message----- > From: Borislav Petkov [mailto:bp@alien8.de] > Sent: Wednesday, April 05, 2017 1:22 PM > To: Ghannam, Yazen <Yazen.Ghannam@amd.com> > Cc: linux-edac@vger.kernel.org; Tony Luck <tony.luck@intel.com>; > x86@kernel.org; linux-kernel@vger.kernel.org > Subject: Re: [PATCH v2 1/2] x86/mce/AMD: Redo use of SMCA > MCA_DE{STAT,ADDR} registers > > On Wed, Apr 05, 2017 at 05:06:19PM +0000, Ghannam, Yazen wrote: > > Checking if we have a valid deferred error. Since we call > > __log_error() on thresholding interrupts too we would need to tell it > > which handler is calling it to do the correct check. This is what we currently > do. > > That's why I suggested a __log_error_deferred() - a separate function which > deals with deferred errors. > > > What do you mean " we don't have anything"? We check if we have a > > valid deferred error in is_deferred_error(). Otherwise, we don't log > anything. > > So the normal status MSR says whether we have a deferred error or not. > If it says we don't, then we have to look at the DE* MSRs, correct? >
Correct, but only on SMCA systems.
> If yes, then do it exactly like this. > > Not: > > IF deferred: > log > ELSE IF SMCA: > IF deferred: > log >
This works so I don't know why it's not okay. Your suggestion also does an SMCA check. So code that does a check-and-return is preferable to code using if/else-if statements? If that's the case then I can try to rework it.
> but: > > IF deferred: > log_deferred: > log > IF cannot log from normal MSRs
How does log_error() know if we can't use the normal MSRs? We check for MCI_STATUS_VAL in log_error(). We also need to check for MCI_STATUS_DEFERRED but only if we're coming from the deferred error handler.
> log from DE > > Why are we even wasting time with this?! >
I don't know.
Thanks, Yazen
| |