On 09/12/2024 09:06, Bernd Schubert wrote: > Hi Malte, > > On 12/9/24 07:42, Malte Schröder wrote: >> On 09/12/2024 02:57, Jingbo Xu wrote: >>> Hi, Malte >>> >>> On 12/9/24 6:32 AM, Malte Schröder wrote: >>>> On 08/12/2024 21:02, Malte Schröder wrote: >>>>> On 08/12/2024 02:23, Matthew Wilcox wrote: >>>>>> On Sun, Dec 08, 2024 at 12:01:11AM +0100, Malte Schröder wrote: >>>>>>> Reverting fb527fc1f36e252cd1f62a26be4906949e7708ff fixes the issue for >>>>>>> me. >>>>>> That's a merge commit ... does the problem reproduce if you run >>>>>> d1dfb5f52ffc? And if it does, can you bisect the problem any further >>>>>> back? I'd recommend also testing v6.12-rc1; if that's good, bisect >>>>>> between those two. >>>>>> >>>>>> If the problem doesn't show up with d1dfb5f52ffc? then we have a dilly >>>>>> of an interaction to debug ;-( >>>>> I spent half a day compiling kernels, but bisect was non-conclusive. >>>>> There are some steps where the failure mode changes slightly, so this is >>>>> hard. It ended up at 445d9f05fa149556422f7fdd52dacf487cc8e7be which is >>>>> the nfsd-6.13 merge ... >>>>> >>>>> d1dfb5f52ffc also shows the issue. I will try to narrow down from there. >>>>> >>>>> /Malte >>>>> >>>> Ha! This time I bisected from f03b296e8b51 to d1dfb5f52ffc. I ended up >>>> with 3b97c3652d91 as the culprit. >>> Would you mind checking if [1] fixes the issue? It is a fix for >>> 3b97c3652d91, though the initial report shows 3b97c3652d91 will cause >>> null-ptr-deref. >>> >>> >>> [1] >>> https://lore.kernel.org/all/20241203-fix-fuse_get_user_pages-v2-1-acce8a29d06b@xxxxxxx/ >> It does not fix the issue, still behaves the same. >> > could you give instructions how to get the issue? Maybe we can script it and I let > it run in a loop on one my systems? > > > Thanks, > Bernd Sure. To reproduce I set up a VM running Arch and bcachefs as rootfs (Works out of the box on current Arch). Build -rc kernel using pacman-pkg build target. Try to install FreeCAD, "flatpak install flathub org.freecad.FreeCAD". Usually it fails to download some dependencies. It's a pretty wonky test, but I didn't find a more specific way to reproduce this. /Malte
