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Subject: Re: [PATCH v9 3/4] kasan: Add report for async mode
To:     Andrey Konovalov <andreyknvl@google.com>,
        Alexander Potapenko <glider@google.com>
Cc:     Linux ARM <linux-arm-kernel@lists.infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        kasan-dev <kasan-dev@googlegroups.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Dmitry Vyukov <dvyukov@google.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Marco Elver <elver@google.com>,
        Evgenii Stepanov <eugenis@google.com>,
        Branislav Rankov <Branislav.Rankov@arm.com>
References: <20210126134603.49759-1-vincenzo.frascino@arm.com>
 <20210126134603.49759-4-vincenzo.frascino@arm.com>
 <CAAeHK+xAbsX9Zz4aKXToNTrbgrrYck23ohGJHXvgeSTyZy=Odg@mail.gmail.com>
 <e5582f87-2987-a258-350f-1fac61822657@arm.com>
 <CAAeHK+x5O595yU9q03G8xPvwpU_3Y6bQhW=+09GziOuTPZNVHw@mail.gmail.com>
From:   Vincenzo Frascino <vincenzo.frascino@arm.com>
Message-ID: <f1ad988d-6385-45e0-d683-048bfca0b9c0@arm.com>
Date:   Fri, 29 Jan 2021 18:16:31 +0000
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On 1/29/21 6:09 PM, Andrey Konovalov wrote:
> On Fri, Jan 29, 2021 at 6:56 PM Vincenzo Frascino
> <vincenzo.frascino@arm.com> wrote:
>>
>> Hi Andrey,
>>
>> On 1/29/21 5:40 PM, Andrey Konovalov wrote:
>>> I suggest to call end_report(&flags, 0) here and check addr !=0 in
>>> end_report() before calling trace_error_report_end().
>>>
>>
>> Probably this is better as:
>>
>> if (!IS_ENABLED(CONFIG_KASAN_HW_TAGS))
>>
>> Because that condition passes always addr == 0.
> 
> Not sure I understand. Call report_end(&flags, 0) and then there do:
> 
> if (addr) trace_error_report_end(...);
> 
> Although maybe it makes sense to still trace all async bugs to address
> 0. Or to some magic address.
> 
> Alex, WDYT?
> 

What I meant is instead of:

if (addr) trace_error_report_end(...);

you might want to do:

if (!IS_ENABLED(CONFIG_KASAN_HW_TAGS)) trace_error_report_end(...);

because, could make sense to trace 0 in other cases?

I could not find the implementation of trace_error_report_end() hence I am not
really sure on what it does.

-- 
Regards,
Vincenzo