Re: [PATCH 6.1 000/440] 6.1.103-rc1 review

[Frank Scheiner <frank.scheiner@web.de>]

Dear Greg,

6259151c04d4e0085e00d2dcb471ebdd1778e72e from mainline is missing in
6.1.103-rc1 and completes 39823b47bbd40502632ffba90ebb34fff7c8b5e8.

Please note that the second hunk from 6259151 needs to be modified to
cleanly apply to 6.1.103-rc1. Example on [1].

[1]:
https://github.com/linux-ia64/linux-stable-rc/blob/__mirror/patches/linux-6.1.y/6259151c04d4e0085e00d2dcb471ebdd1778e72e.patch

****

## Long version ##

This patch series breaks operation of the hp-sim kernel in ski. I think
it happens when trying to access the ext4 root FS in the simulation, see
for example [2] for more details.

[2]: https://github.com/linux-ia64/linux-stable-rc/issues/3

 From the call trace:
```
[...]
[<a0000001000263f0>] die+0x1b0/0x3e0
[<a00000010004bd40>] ia64_do_page_fault+0x680/0x9c0
[<a00000010000c4e0>] ia64_leave_kernel+0x0/0x280
[<a00000010063f6a0>] dd_limit_depth+0x80/0x140
[...]
```

...I tracked it down to [3] and following the linked discussion ([4]),
this is actually patch 2 of 2. And 1 of 2 ([5]) is in upstream, but not
in 6.1.103-rc1.

[3]:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=39823b47bbd40502632ffba90ebb34fff7c8b5e8

[4]: https://lore.kernel.org/all/20240509170149.7639-3-bvanassche@acm.org/

[5]:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6259151c04d4e0085e00d2dcb471ebdd1778e72e

Applying that patch ([5]) (plus adapting hunk #2 of it) on top of
6.1.103-rc1 fixes it for me ([6]).

[6]:
https://github.com/linux-ia64/linux-stable-rc/actions/runs/10170700172#summary-28130632329

Cheers,
Frank