From: Vincenzo Frascino <vincenzo.frascino@arm.com>
To: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrey Konovalov <andreyknvl@google.com>,
Will Deacon <will.deacon@arm.com>,
Dmitry Vyukov <dvyukov@google.com>,
Andrey Ryabinin <aryabinin@virtuozzo.com>,
Alexander Potapenko <glider@google.com>,
Marco Elver <elver@google.com>,
Evgenii Stepanov <eugenis@google.com>,
Branislav Rankov <Branislav.Rankov@arm.com>,
Kevin Brodsky <kevin.brodsky@arm.com>,
Andrew Morton <akpm@linux-foundation.org>,
kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org,
linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v9 32/44] arm64: mte: Switch GCR_EL1 in kernel entry and exit
Date: Thu, 12 Nov 2020 09:55:05 +0000 [thread overview]
Message-ID: <6aec6a77-f9b0-cf73-6bf3-4f8df8f8cd13@arm.com> (raw)
In-Reply-To: <20201112094553.GG29613@gaia>
On 11/12/20 9:45 AM, Catalin Marinas wrote:
> On Thu, Nov 12, 2020 at 09:45:45AM +0000, Vincenzo Frascino wrote:
>> On 11/12/20 9:39 AM, Catalin Marinas wrote:
>>> On Tue, Nov 10, 2020 at 11:10:29PM +0100, Andrey Konovalov wrote:
>>>> diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c
>>>> index 664c968dc43c..dbda6598c19d 100644
>>>> --- a/arch/arm64/kernel/mte.c
>>>> +++ b/arch/arm64/kernel/mte.c
>>>> @@ -129,6 +131,26 @@ void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag)
>>>> return ptr;
>>>> }
>>>>
>>>> +void mte_init_tags(u64 max_tag)
>>>> +{
>>>> + static bool gcr_kernel_excl_initialized = false;
>>>> +
>>>> + if (!gcr_kernel_excl_initialized) {
>>>> + /*
>>>> + * The format of the tags in KASAN is 0xFF and in MTE is 0xF.
>>>> + * This conversion extracts an MTE tag from a KASAN tag.
>>>> + */
>>>> + u64 incl = GENMASK(FIELD_GET(MTE_TAG_MASK >> MTE_TAG_SHIFT,
>>>> + max_tag), 0);
>>>> +
>>>> + gcr_kernel_excl = ~incl & SYS_GCR_EL1_EXCL_MASK;
>>>> + gcr_kernel_excl_initialized = true;
>>>> + }
>>>> +
>>>> + /* Enable the kernel exclude mask for random tags generation. */
>>>> + write_sysreg_s(SYS_GCR_EL1_RRND | gcr_kernel_excl, SYS_GCR_EL1);
>>>> +}
>>>
>>> I don't think this function belongs to this patch. There is an earlier
>>> patch that talks about mte_init_tags() but no trace of it until this
>>> patch.
>>
>> Could you please point out to which patch are you referring to?
>
> I replied to it already (or you can search ;)). But this patch is about
> switching GCR_EL1 on exception entry/exit rather than setting up the
> initial kernel GCR_EL1 value.
>
Temporally after I asked ;) (I give you the benefit of delay of the mail server
;) ). I think that during the development the logic changed a bit, but I agree
that the comments are outdated. I am fine to move the code.
--
Regards,
Vincenzo
next prev parent reply other threads:[~2020-11-12 9:52 UTC|newest]
Thread overview: 107+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-10 22:09 [PATCH v9 00/44] kasan: add hardware tag-based mode for arm64 Andrey Konovalov
2020-11-10 22:09 ` [PATCH v9 01/44] kasan: drop unnecessary GPL text from comment headers Andrey Konovalov
2020-11-11 13:16 ` Alexander Potapenko
2020-11-10 22:09 ` [PATCH v9 02/44] kasan: KASAN_VMALLOC depends on KASAN_GENERIC Andrey Konovalov
2020-11-11 13:19 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 03/44] kasan: group vmalloc code Andrey Konovalov
2020-11-11 13:21 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 04/44] s390/kasan: include asm/page.h from asm/kasan.h Andrey Konovalov
2020-11-10 22:10 ` [PATCH v9 05/44] kasan: shadow declarations only for software modes Andrey Konovalov
2020-11-11 13:25 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 06/44] kasan: rename (un)poison_shadow to (un)poison_memory Andrey Konovalov
2020-11-11 13:26 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 07/44] kasan: rename KASAN_SHADOW_* to KASAN_GRANULE_* Andrey Konovalov
2020-11-11 13:45 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 08/44] kasan: only build init.c for software modes Andrey Konovalov
2020-11-11 13:46 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 09/44] kasan: split out shadow.c from common.c Andrey Konovalov
2020-11-11 14:07 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 10/44] kasan: define KASAN_GRANULE_PAGE Andrey Konovalov
2020-11-11 14:13 ` Alexander Potapenko
2020-11-11 18:47 ` Andrey Konovalov
2020-11-11 19:04 ` Marco Elver
2020-11-12 0:05 ` Andrey Konovalov
2020-11-10 22:10 ` [PATCH v9 11/44] kasan: rename report and tags files Andrey Konovalov
2020-11-11 14:15 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 12/44] kasan: don't duplicate config dependencies Andrey Konovalov
2020-11-11 14:20 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 13/44] kasan: hide invalid free check implementation Andrey Konovalov
2020-11-11 14:23 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 14/44] kasan: decode stack frame only with KASAN_STACK_ENABLE Andrey Konovalov
2020-11-11 14:25 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 15/44] kasan, arm64: only init shadow for software modes Andrey Konovalov
2020-11-11 14:30 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 16/44] kasan, arm64: only use kasan_depth " Andrey Konovalov
2020-11-11 14:59 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 17/44] kasan, arm64: move initialization message Andrey Konovalov
2020-11-11 15:03 ` Alexander Potapenko
2020-11-11 18:50 ` Andrey Konovalov
2020-11-12 15:09 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 18/44] kasan, arm64: rename kasan_init_tags and mark as __init Andrey Konovalov
2020-11-11 15:05 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 19/44] kasan: rename addr_has_shadow to addr_has_metadata Andrey Konovalov
2020-11-11 15:06 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 20/44] kasan: rename print_shadow_for_address to print_memory_metadata Andrey Konovalov
2020-11-11 15:07 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 21/44] kasan: kasan_non_canonical_hook only for software modes Andrey Konovalov
2020-11-11 15:08 ` Alexander Potapenko
2020-11-11 18:52 ` Andrey Konovalov
2020-11-12 15:16 ` Alexander Potapenko
2020-11-12 19:27 ` Andrey Konovalov
2020-11-10 22:10 ` [PATCH v9 22/44] kasan: rename SHADOW layout macros to META Andrey Konovalov
2020-11-11 15:18 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 23/44] kasan: separate metadata_fetch_row for each mode Andrey Konovalov
2020-11-11 15:22 ` Alexander Potapenko
2020-11-11 16:19 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 24/44] kasan, arm64: don't allow SW_TAGS with ARM64_MTE Andrey Konovalov
2020-11-11 15:52 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 25/44] kasan: introduce CONFIG_KASAN_HW_TAGS Andrey Konovalov
2020-11-11 15:58 ` Alexander Potapenko
2020-11-11 18:53 ` Andrey Konovalov
2020-11-10 22:10 ` [PATCH v9 26/44] arm64: Enable armv8.5-a asm-arch option Andrey Konovalov
2020-11-10 22:10 ` [PATCH v9 27/44] arm64: mte: Add in-kernel MTE helpers Andrey Konovalov
2020-11-10 22:10 ` [PATCH v9 28/44] arm64: mte: Reset the page tag in page->flags Andrey Konovalov
2020-11-12 9:31 ` Catalin Marinas
2020-11-12 9:39 ` Vincenzo Frascino
2020-11-10 22:10 ` [PATCH v9 29/44] arm64: mte: Add in-kernel tag fault handler Andrey Konovalov
2020-11-10 22:10 ` [PATCH v9 30/44] arm64: kasan: Allow enabling in-kernel MTE Andrey Konovalov
2020-11-12 9:43 ` Catalin Marinas
2020-11-12 16:46 ` Vincenzo Frascino
2020-11-13 11:17 ` Vincenzo Frascino
2020-11-13 12:00 ` Catalin Marinas
2020-11-13 12:04 ` Vincenzo Frascino
2020-11-10 22:10 ` [PATCH v9 31/44] arm64: mte: Convert gcr_user into an exclude mask Andrey Konovalov
2020-11-10 22:10 ` [PATCH v9 32/44] arm64: mte: Switch GCR_EL1 in kernel entry and exit Andrey Konovalov
2020-11-12 9:39 ` Catalin Marinas
2020-11-12 9:45 ` Vincenzo Frascino
2020-11-12 9:45 ` Catalin Marinas
2020-11-12 9:55 ` Vincenzo Frascino [this message]
2020-11-10 22:10 ` [PATCH v9 33/44] kasan, mm: untag page address in free_reserved_area Andrey Konovalov
2020-11-10 22:10 ` [PATCH v9 34/44] arm64: kasan: Align allocations for HW_TAGS Andrey Konovalov
2020-11-11 16:10 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 35/44] arm64: kasan: Add arch layer for memory tagging helpers Andrey Konovalov
2020-11-10 22:10 ` [PATCH v9 36/44] kasan: define KASAN_GRANULE_SIZE for HW_TAGS Andrey Konovalov
2020-11-11 16:13 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 37/44] kasan, x86, s390: update undef CONFIG_KASAN Andrey Konovalov
2020-11-11 16:15 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 38/44] kasan, arm64: expand CONFIG_KASAN checks Andrey Konovalov
2020-11-11 16:22 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 39/44] kasan, arm64: implement HW_TAGS runtime Andrey Konovalov
2020-11-12 17:37 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 40/44] kasan, arm64: print report from tag fault handler Andrey Konovalov
2020-11-11 16:43 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 41/44] kasan, mm: reset tags when accessing metadata Andrey Konovalov
2020-11-12 16:10 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 42/44] kasan, arm64: enable CONFIG_KASAN_HW_TAGS Andrey Konovalov
2020-11-11 16:49 ` Alexander Potapenko
2020-11-10 22:10 ` [PATCH v9 43/44] kasan: add documentation for hardware tag-based mode Andrey Konovalov
2020-11-11 16:57 ` Alexander Potapenko
2020-11-11 18:54 ` Andrey Konovalov
2020-11-10 22:10 ` [PATCH v9 44/44] kselftest/arm64: Check GCR_EL1 after context switch Andrey Konovalov
2020-11-12 9:46 ` Catalin Marinas
2020-11-12 15:59 ` Alexander Potapenko
2020-11-12 16:09 ` Marco Elver
2020-11-12 16:41 ` Alexander Potapenko
2020-11-13 11:47 ` Vincenzo Frascino
2020-11-10 22:54 ` [PATCH v9 00/44] kasan: add hardware tag-based mode for arm64 Andrew Morton
2020-11-11 14:35 ` Andrey Konovalov
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