在2023年10月20日十月 下午12:04，Thorsten Leemhuis写道： > Hi, Thorsten here, the Linux kernel's regression tracker. Top-posting > for once, to make this easily accessible to everyone. > > Just wondering what's up here. The patch this thread is about afaics was > supposed to fix a regression reported in July > (https://bugzilla.kernel.org/show_bug.cgi?id=217680 ), but has made not > steps closer to get mainlined during the past few weeks. Is there a > reason, or did it maybe fell through the cracks? > > Jiaxun Yang, from it quick look it seems like you wanted to post a v3, > but never did so; but I might be mistaken there. I just figure out the problem of this implementation. Will resend and explain. Thanks - Jiaxun > > Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) > -- > Everything you wanna know about Linux kernel regression tracking: > https://linux-regtracking.leemhuis.info/about/#tldr > If I did something stupid, please tell me, as explained on that page. > > #regzbot poke > > On 20.09.23 14:33, Linux regression tracking (Thorsten Leemhuis) wrote: >> [CCing the regression list, as it should be in the loop for regressions: >> https://docs.kernel.org/admin-guide/reporting-regressions.html] >> >> On 07.09.23 07:08, Manivannan Sadhasivam wrote: >>> On Thu, Sep 07, 2023 at 11:13:00AM +0800, Jiaxun Yang wrote: >>>> 在 2023/9/7 9:18, Manivannan Sadhasivam 写道: >>>> [...] >>>>> Why do you need to walk through every single device instead of just bridges? >>>>> I'm not the maintainer, but my suggestion is to go for Huacai Chen's solution. >>>> >>>> Thanks for your reply, unfortunately Huacai's solution is impractical in >>>> this case. >>>> >>>> The problem we have, is firmware (or BIOS) setting improper MRRS for devices >>>> attached under those bridges. So we have to fix up MRRS for every single >>>> device. >>>> We can't iterate child device in bridge quirk because there is no guarantee >>>> that >>>> bridge will be probed before it's child device, partly due to hotplug. >>> >>> Okay, this clarifies and also warrants improvement in commit message. >>> >>> You could also use pci_walk_bus() after pci_host_probe() to iterate over the >>> child devices under root bridge and set MRRS. IMO that would look neat. >> >> Hi, Thorsten here, the Linux kernel's regression tracker. What's the >> status here? The regression that was supposed to be fixed by the patched >> that started this thread was reported 9 weeks ago[1] and the culprit >> made it to many stable kernels as well. Would be really good to finally >> fix this, as a regression like this should ideally be fixed within 2 to >> 3 weeks (in both mainline and stable). With a revert if necessary -- is >> this maybe still a option, or would that cause more trouble then it >> solved (I guess that's the case). >> >> [1] https://bugzilla.kernel.org/show_bug.cgi?id=217680 >> >> Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) >> -- >> Everything you wanna know about Linux kernel regression tracking: >> https://linux-regtracking.leemhuis.info/about/#tldr >> If I did something stupid, please tell me, as explained on that page. >> >>>> This quirk has been in tree for a while, until Huacai refactored it and >>>> broke some >>>> systems in 8b3517f88ff2 ("PCI: loongson: Prevent LS7A MRRS increases"). >>>> >>>> Also to note that ks_pcie_quirk in drivers/pci/controller/dwc/pci-keystone.c >>>> uses similar approach. >>>>> This avoids iterating over bridges/devices two times. >>>>> >>>>> Also, please rename firmware to BIOS, as firmware commonly represents the >>>>> software running on PCIe endpoint devices. >>>> Ack, will fix in next reversion. >>>> >>>> Thanks >>>> - Jiaxun >>>>> >>>>> - Mani >>>> [...] >>> -- - Jiaxun
