On 03/30/2018 09:45 AM, Kani, Toshi wrote: > On Fri, 2018-03-30 at 09:38 -0700, Dan Williams wrote: >> On Fri, Mar 30, 2018 at 8:04 AM, Kani, Toshi <toshi.kani@xxxxxxx> wrote: >>> On Thu, 2018-03-29 at 15:37 -0700, Dave Jiang wrote: >>>> The following series implements support for parsing of the BERT records >>>> and adding the error memory ranges to nvdimm badblocks in order for the >>>> kernel to avoid prevent the kernel from accessing those areas. And with >>>> the addition of this support, we can surface the nd regions instead of waiting >>>> for ARS to complete. So the ARS handling is reworked to run in the >>>> background and not block nd region registration. >>> >>> Hi Dave, >>> >>> I agree on the problem, and adding an ability to obtain pmem badblocks >>> records at boot-time without waiting for a new ARS scan to complete is a >>> good option for users. >>> >>> However, I do not think using the BERT table is a good approach. This >>> requires FW to report pmem badblocks records with a new interface in >>> addition to ARS records, which FW already implements for pmem. ACPI 6.2 >>> defines Start ARS with Flags Bit[1] set to report badblocks record >>> without starting a new ARS scan. We set this bit after receiving a 0x81 >>> notification at this point. >>> >>> Can we use ARS with Flags bit[1] set at boot-time so that both OS and FW >>> can use the same ARS implementation? >> >> You have a point. >> >> The other benefit I see to this policy is that it hopefully convinces >> BIOS implementations to not run ARS at boot and leave it to the OS to >> manage it in the background. If the platform has any critical errors >> to report, i.e. ones that triggered a system reset, then it should be >> able to report them in the flag-bit1 case. > > Agreed. > >> This also lets the implementation be completely self contained to the >> nfit driver, and not grow any BERT entanglements that may or may not >> be valid for the persistent memory case. > > Right. Thanks Dan! > -Toshi > Ok, I'll respin the series with what you suggested Toshi and drop the BERT stuff. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
