Re: [PATCH v19 00/14] arm64: entry: Convert to Generic Entry

[Kees Cook]

On Thu, Sep 24, 2026 at 05:32:14PM +0800, Jinjie Ruan wrote:
> 在 2026/9/23 2:29, Kees Cook 写道:
> I tested the rr test cases on a Kunpeng HIP09 (with minor adaptations,
> since Kunpeng CPUs aren't supported by default), and the results showed
> no regressions.

Great! Thank you for getting that set up.

> 
> |               |    7.3-rc4 baseline     |   Patched                 |
> 
> |  ------------ |------------------------ | ------------------------- |
> |   result      |  87% passed, 190 failed |   88% passed, 186 failed  |
> 
> 
> | Failure Mode   | 7.3-rc4 baseline |   Patched  |
> | ------------   | ---------------- | ---------- |
> | TICK_MISMATCH  |         76       |   74       |
> | TIMEOUT        |         68       |   65       |
> | GDB_SCRIPT     |         34       |   37       |
> | PERF_EVENT_OPEN|         3        |   2        |
> |   OVERSHOOT    |         1        |   0        |
> |    OTHER       |         8        |   8        |
> | -------------- |  --------------- | ---------- |
> |  Total         |      190         |   186      |

GDB_SCRIPT failures went up? Are the tests just flaky?

> > - MTE: I didn't see MTE in the cover letter's test list, and it seems
> >   relevant since patch 13 puts _TIF_MTE_ASYNC_FAULT into
> >   ARCH_EXIT_TO_USER_MODE_WORK, so an async tag check fault lands
> >   on the reworked exit path. The MTE selftests showed no differences,
> >   but a third of them don't actually run for me under QEMU, so they'd
> >   be worth running on your hardware. (Testing MTE under QEMU saw
> 
> Turns out our arm64 machines don't support MTE; I was testing it on QEMU.

Ah, dang. I wonder if we can find anyone with MTE hardware to test this.
Any volunteers? :)

-Kees

-- 
Kees Cook