On Tuesday, November 27, 2018 9:25:14 PM CET Bjorn Helgaas wrote: > On Mon, Nov 26, 2018 at 11:37:20PM +0100, Rafael J. Wysocki wrote: > > On Monday, November 26, 2018 7:03:58 PM CET Rafael J. Wysocki wrote: > > > Hi Bjorn, > > > > > > The SD card reader in my Acer Aspire S5 doesn't work with 4.20-rc. > > > > > > Here's what lspci -v says about it (in a bad kernel): > > > > > > 02:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5209 PCI Express Card Reader > > > (rev 01) > > > Subsystem: Acer Incorporated [ALI] Device 0704 > > > Flags: bus master, fast devsel, latency 0, IRQ 35 > > > Memory at d9001000 (32-bit, non-prefetchable) [size=4K] > > > Capabilities: [40] Power Management version 3 > > > Capabilities: [50] MSI: Enable+ Count=1/1 Maskable- 64bit+ > > > Capabilities: [70] Express Endpoint, MSI 00 > > > Capabilities: [100] Advanced Error Reporting > > > Capabilities: [140] Device Serial Number 00-00-00-01-00-4c-e0-00 > > > Kernel driver in use: rtsx_pci > > > Kernel modules: rtsx_pci > > Thanks a lot for bisecting this! > > With a good kernel (v4.19 or v4.20-rc with 17c91487364f reverted), > would you mind collecting "lspci -vv" output, the dmesg log with > "pci=earlydump", and the FADT dump? I'll do that tomorrow. > I'm interested in the initial state of the device at handoff from > BIOS, and what Linux changes even when aspm_disabled is set. OK > If we can't figure out a way to fix both this issue and the one fixed > by 17c91487364f, I guess the fallback will be to revert 17c91487364f > since it's better to allow a system that was previously broken to > remain broken than it is to break a system that previously worked. Well, depending on how many systems are affected by the issues fixed by 17c91487364f IMO. Arguably, if the FADT says "NO_ASPM", then the platform should not need the OS to initialize ASPM to work. I guess a manual workaround (like an extra kernel command line option or similar) should suffice in this particular case. > But obviously I hope we can figure out a solution that fixes both > cases. Of course.
