Re: [Qemu-devel] [PATCH] exec: fix breakpoint_invalidate() breakage

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2012-05-23 13:02, Jan Kiszka wrote:
> On 2012-05-23 11:11, TeLeMan wrote:
>> On Wed, May 23, 2012 at 7:22 PM, Jan Kiszka <jan.kiszka@siemens.com> wrote:
>>> On 2012-05-23 04:09, TeLeMan wrote:
>>>> On Wed, May 23, 2012 at 11:41 AM, Andreas Färber <afaerber@suse.de> wrote:
>>>>> Am 18.05.2012 11:49, schrieb TeLeMan:
>>>>>> This breakage was introduced by the commit "memory: make
>>>>>> phys_page_find() return an unadjusted".
>>>>>
>>>>> You seem to have found the origin of your problem. If you also mention
>>>>> the commit hash in your commit message then certain frontends (gitk,
>>>>> repo.or.cz) will display it as a handy hyperlink to that commit.
>>>>>
>>>>>>
>>>>>> Signed-off-by: TeLeMan <geleman@gmail.com>
>>>>>
>>>>> Signed-off-by is a legal statement of origin and must not be a pseudonym.
>>>> Ok, please ignore this patch. I won't submit any patch just report bugs.
>>>
>>> Then please describe this bug in more details, e.g. how to reproduce.
>> I think its evident. cpu_get_phys_page_debug(env, pc) is not the
>> physical address of pc but the physical page base address of pc.
> 
> ...so this bites us if the instruction spans two pages as
> tb_invalidate_phys_addr requests invalidation on a page granularity.

In fact, this is irrelevant. We only need to flush the address at which
the instruction starts, and that is achieved by flushing all TB that
relate to that page as the current code does.

So, again my question: How can I reproduce the issue you see?

Jan

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