Hi, On 22.03.21 22:48, John Paul Adrian Glaubitz wrote:
On 3/22/21 10:30 PM, Frank Scheiner wrote:Riccardo Mottola first recognized a problem with 5.10.x kernels on his Sun T2000 with UltraSPARC T1 (details in [this thread]). I could verify the problem also on my Sun T1000 and it looks like this specific issue breaks the mounting of the root FS or maybe mounting file systems at all. This affects both booting from disk and from network. (...) ...as first bad commit. ``` commit 028abd9222df0cf5855dab5014a5ebaf06f90565 Author: Christoph Hellwig <hch@xxxxxx> Date: Thu Sep 17 10:22:34 2020 +0200 fs: remove compat_sys_mount compat_sys_mount is identical to the regular sys_mount now, so remove it and use the native version everywhere. ``` [1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=028abd9222df0cf5855dab5014a5ebaf06f90565Looking at this change, I think it's rather unexpected that this particular change would break the kernel on a specific CPU target. Are you sure that this is the right bad commit?
Well, I strictly followed the `git bisect` process and tested each and every proposed revision. It's indeed strange that this only affects UltraSPARC T1s, but the changes match the behavior: mounting of (root) FS is broken.
If you found the right commit, then I assume there is something wrong with the syscall handling on UltraSPARC T1.
Could be, all in all the T1 is a first of its kind. Cheers, Frank
