On Mon, Nov 19, 2018 at 12:32:42PM -0500, Sinan Kaya wrote: > On 11/19/2018 11:53 AM, Keith Busch wrote: > > On Mon, Nov 19, 2018 at 11:53:05AM -0500, Tyler Baicar wrote: > > > On Thu, Nov 15, 2018 at 8:49 PM Sinan Kaya <okaya@xxxxxxxxxx> wrote: > > > > > > > > On 11/15/2018 3:16 PM, Alexandru Gagniuc wrote: > > > > > I've asked around a few people at Dell and they unanimously agree that > > > > > _OSC is the correct way to determine ownership of AER. In linux, we > > > > > use the result of _OSC to enable AER services, but we use HEST to > > > > > determine AER ownership. That's inconsistent. This series drops the > > > > > use of HEST in favor of _OSC. > > > > > > > > > > [1]https://lkml.org/lkml/2018/11/15/62 > > > > > > > > This change breaks the existing systems that rely on the HEST table > > > > telling the operating system about firmware first presence. > > > > > > > > Besides, HEST table has much more granularity about which PCI component > > > > needs firmware such as global/device/switch. > > > > > > > > You should probably circulate these ideas for wider consumption in UEFI > > > > forum as UEFI owns the HEST table definition. > > > > > > I agree with Sinan, this will break existing systems, and the granularity of the > > > HEST definition is more useful than the single bit in _OSC. > > > > But we're not using HEST as a fine grain control. We disable native AER > > handling if *any* device has FF set in HEST, and that just forces people > > to use pcie_ports=native to get around that. > > > > I don't see *any* in the code. aer_hest_parse() does the HEST table parsing. > It switches to firmware first mode if global flag in HEST is set. Otherwise > for each BDF in device, hest_match_pci() is used to do a cross-matching against > HEST table contents. > > Am I missing something? You might be. :) static int aer_hest_parse(struct acpi_hest_header *hest_hdr, void *data) { <snip> /* * If no specific device is supplied, determine whether * FIRMWARE_FIRST is set for *any* PCIe device. */ if (!info->pci_dev) { info->firmware_first |= ff; return 0; }
