Re: [PATCH v3] target/arm: handle unaligned PC during tlb probe

["Alex Bennée" <alex.bennee@linaro.org>]

Michael Tokarev <mjt@tls.msk.ru> writes:

> On 12/4/25 23:35, Alex Bennée wrote:
>> PC alignment faults have priority over instruction aborts and we have
>> code to deal with this in the translation front-ends. However during
>> tb_lookup we can see a potentially faulting probe which doesn't get a
>> MemOp set. If the page isn't available this results in
>> EC_INSNABORT (0x20) instead of EC_PCALIGNMENT (0x22).
>> As there is no easy way to set the appropriate MemOp in the
>> instruction fetch probe path lets just detect it in
>> arm_cpu_tlb_fill_align() ahead of the main alignment check. We also
>> teach arm_deliver_fault to deliver the right syndrome for
>> MMU_INST_FETCH alignment issues.
>> Fixes: https://gitlab.com/qemu-project/qemu/-/issues/3233
>> Tested-by: Jessica Clarke <jrtc27@jrtc27.com>
>> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
>
> This feels like a qemu-stable material (for all active stable
> branches).

By all means - its pretty self-contained.

>
> I'm picking it up for 10.0.x and 10.1.x.  Please let me know
> if I shouldn't.
>
> Thanks,
>
> /mjt

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro