Re: another tst-arm-mte bug: qemu-system segfaults

[Richard Henderson]

On 6/3/20 10:17 AM, Szabolcs Nagy wrote:
> The 06/03/2020 09:21, Richard Henderson wrote:
>> On 6/3/20 6:50 AM, Szabolcs Nagy wrote:
>>> thanks my tests now get further but later i run into
>>> the previous assert failure:
>>>
>>> target/arm/mte_helper.c:97:allocation_tag_mem: assertion failed: (tag_size 
>>> <= in_page)
>>>
>>> i might be able to reduce it to a small reproducer
>>> this time. i assume that will help.
>>
>> Dang, I had hoped that the one fix would cover both -- it's definitely in the
>> same area.  Yes, a small reproducer will help, but I will also try again with
>> your larger reproducer.
> 
> reproducer .c and static exe attached.
> 
> the referenced __memcmp_aarch64 is again
> from the arm optimized-routines repo.

That assert is just wrong -- it's attempting to sanity check a virtual address
against a property associated with the physical address, and even doing that
incorrectly.

I've pushed a fixup to the branch to remove it, and I'll look into adding a
correct assertion later.


r~