Hey, On Sat, 2023-01-14 at 16:30 +0100, Salvatore Bonaccorso wrote: > Hi, > > On Thu, Jan 12, 2023 at 02:51:05PM +0100, Diederik de Haas wrote: > > On Thursday, 12 January 2023 12:03:24 CET Sjoerd Simons wrote: > > > Fwiw there is a general regression with AMDGPU MST on linux 6.1; tracked > > > upstream here: > > > https://gitlab.freedesktop.org/drm/amd/-/issues/2171 > > > > Thanks! About an hour ago the suggested fix was to revert commit > > 4d07b0bc403403438d9cf88450506240c5faf92f part of v6.1-rc1 > > > > https://kernel-team.pages.debian.net/kernel-handbook/ch-common-tasks.html#s4.2.2 > > describes a procedure to build a kernel with the proposed patch (attached). > > > > OdyX: Can you try to see whether that resolves the issue? > > Should we keep 6.1.y based kernel out of testing until this is clear?
Basically this issue breaks all usage of Displayport MST on amdgpu systems. Which roughly translates to breaking external monitors for everyone using an USB-C docks with multiple display outputs (which is pretty common these days) on AMD laptops. As well as those like myself who daisy-chain display port monitors with an amdgpu using graphics card. So I would expect this impacts a lot of people :/ Which is also why there is loads of activity and duplicates on the fd.o bug now that 6.1 is trickling into distributions. > As we aim though to have 6.1.y into bookworm I would see it as more > preferable to get 6.1.4 in for testing, we will need to followup as > well soonish with another interation for e.g. for fixing > CVE-2023-0266. > > Now if it turns out that this is the same issue as the referenced > upstream, reverting I think we only should really revert the commit if > that's queued up for 6.1. There is currently some furhter discussion > on > https://lore.kernel.org/stable/dcf0612f-7d40-d607-e9aa-94599594e...@amd.com/T/#m38bdafb9c6c64b167ec94ac1bd131f1d2db66e4 > Given the size of the revert, there is as well a chance to re-break > other parts. So preferring to closely follow upstream here, whatever > the decision will be. For what it's worth; The revert as currently suggested also reverts big chunks for Intel and nvidia based GPUs, which unsurprisingly the maintainers of those aren't too thrilled about. And really i'd be amazed if it doesn't cause regressions for those systems... Unless the AMD folks pull a small/targetted fix out their hats, this is likely going to take weeks if not months before it's resolved in a way that's acceptable for 6.1.y :/.... -- Sjoerd Simons <sjo...@luon.net>
