Re: [PATCH v3 30/39] arm64: kasan: Enable TBI EL1

From: Vincenzo Frascino
Date: Fri Sep 25 2020 - 07:44:33 EST




On 9/25/20 12:37 PM, Catalin Marinas wrote:
> On Fri, Sep 25, 2020 at 12:50:37AM +0200, Andrey Konovalov wrote:
>> diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
>> index 12ba98bc3b3f..dce06e553c7c 100644
>> --- a/arch/arm64/mm/proc.S
>> +++ b/arch/arm64/mm/proc.S
>> @@ -40,9 +40,13 @@
>> #define TCR_CACHE_FLAGS TCR_IRGN_WBWA | TCR_ORGN_WBWA
>>
>> #ifdef CONFIG_KASAN_SW_TAGS
>> -#define TCR_KASAN_FLAGS TCR_TBI1
>> +#define TCR_KASAN_SW_FLAGS TCR_TBI1
>> #else
>> -#define TCR_KASAN_FLAGS 0
>> +#define TCR_KASAN_SW_FLAGS 0
>> +#endif
>> +
>> +#ifdef CONFIG_KASAN_HW_TAGS
>> +#define TCR_KASAN_HW_FLAGS TCR_TBI1
>> #endif
>>
>> /*
>> @@ -454,6 +458,9 @@ SYM_FUNC_START(__cpu_setup)
>>
>> /* set the TCR_EL1 bits */
>> orr mte_tcr, mte_tcr, #SYS_TCR_EL1_TCMA1
>> +#ifdef CONFIG_KASAN_HW_TAGS
>> + orr mte_tcr, mte_tcr, #TCR_KASAN_HW_FLAGS
>> +#endif
>
> I missed this in an earlier patch. Do we need TCMA1 set without
> KASAN_HW? If not, we could add them both to TCR_KASAN_HW_FLAGS.
>

We don't. I will move the code around in the next version.

--
Regards,
Vincenzo