From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7E61BC433F5 for ; Wed, 6 Oct 2021 23:07:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 609F8610CE for ; Wed, 6 Oct 2021 23:07:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239701AbhJFXI6 (ORCPT ); Wed, 6 Oct 2021 19:08:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45418 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237338AbhJFXI4 (ORCPT ); Wed, 6 Oct 2021 19:08:56 -0400 Received: from mail-il1-x12e.google.com (mail-il1-x12e.google.com [IPv6:2607:f8b0:4864:20::12e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 33337C061746 for ; Wed, 6 Oct 2021 16:07:04 -0700 (PDT) Received: by mail-il1-x12e.google.com with SMTP id b6so4552847ilv.0 for ; Wed, 06 Oct 2021 16:07:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=WbOa4HLIAaIjrUBwOZYmdK4mBEVDQc4YiH+cLFPMjPc=; b=X6Vwq7uOazKjNhhzKo53msWaTeuyyVuxSuTXFK80H4tr+sLASUM1Zev2R4vnBA7hbL tuFuXmeCBVL74JUJjNboZjO5jmVhSBE+Qm9fk1uwZ/LUHsNQ6DCouoHGpUCAsIs47Q4C SDAqIebq6SdAiOHWh72ugZUV09woJfDm5jZtcr56Qrxrb46a+qpGAEKXYkcpJTVLnHft SHjLCYj2+gTBZTTvzMwZ+jqYwWfcg3iikdkP3Sbo0lsm4rMCMLyWUIQcviKjHj4fawAJ hdDsFraMnR1FLictAeWz1ZffT/bQVq7dSK8RhUjc/F6+HK74VfXli1a9JHiy6TOSWRQt K7UA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=WbOa4HLIAaIjrUBwOZYmdK4mBEVDQc4YiH+cLFPMjPc=; b=UaX4S/KEvVhF0Q+48zifnvosHia3u1QmgH4LejNCT7Z+OK77d9cTB70Pht61bF3Q8v Z6vR2h2oJh3kGhp1rsEeKOJ9ZtPrkn/GeXawvQ6mIcQNIdaR0frflcdqoYBMLCYsb12i z15ZsJHVE7C0kZVU04jDsHPLvB6iD+AETVolZaH8bvZwjIaD1PgCkmXIjU6e/b8md3WZ K5yKnEVN3EaLUur+0howe4Z/xbkeG+X+zfrtcCEdd7zQoe0GpoqlArKVt+WN4/m/uCqU m2mdwgN65xL9mGA/867NOJ92k3JLQi+zKSjrLTWAxEl84aHI5mhPX3ptBD58grXpRoVT fAEA== X-Gm-Message-State: AOAM533BjAJbUyHd0AeHgn/XzTQZKlKJmRyDw1qN57m4HsI7NMJwxd3B xrR9oYXAeXrTiWeXC/UKb8fCJRfPcWML2iFIu+w= X-Google-Smtp-Source: ABdhPJznl1/8+WJnN2hdHNrV9XCpBNc4ffbFtk5L7M5T1BfnmgVS3CrDbw/mu/k/F/8H5fLPR2tuWL+mGljmkkGq9Bk= X-Received: by 2002:a05:6e02:1a69:: with SMTP id w9mr641955ilv.235.1633561623667; Wed, 06 Oct 2021 16:07:03 -0700 (PDT) MIME-Version: 1.0 References: <20211006154751.4463-1-vincenzo.frascino@arm.com> <20211006154751.4463-6-vincenzo.frascino@arm.com> In-Reply-To: <20211006154751.4463-6-vincenzo.frascino@arm.com> From: Andrey Konovalov Date: Thu, 7 Oct 2021 01:06:53 +0200 Message-ID: Subject: Re: [PATCH v3 5/5] kasan: Extend KASAN mode kernel parameter To: Vincenzo Frascino Cc: Linux ARM , LKML , kasan-dev , Andrew Morton , Catalin Marinas , Will Deacon , Dmitry Vyukov , Andrey Ryabinin , Alexander Potapenko , Marco Elver , Evgenii Stepanov , Branislav Rankov , Lorenzo Pieralisi Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org .On Wed, Oct 6, 2021 at 5:48 PM Vincenzo Frascino wrote: > > Architectures supported by KASAN_HW_TAGS can provide an asymmetric mode > of execution. On an MTE enabled arm64 hw for example this can be > identified with the asymmetric tagging mode of execution. In particular, > when such a mode is present, the CPU triggers a fault on a tag mismatch > during a load operation and asynchronously updates a register when a tag > mismatch is detected during a store operation. > > Extend the KASAN HW execution mode kernel command line parameter to > support asymmetric mode. > > Cc: Dmitry Vyukov > Cc: Andrey Ryabinin > Cc: Alexander Potapenko > Cc: Andrey Konovalov > Signed-off-by: Vincenzo Frascino > Reviewed-by: Catalin Marinas > --- > Documentation/dev-tools/kasan.rst | 7 +++++-- > lib/test_kasan.c | 2 +- > mm/kasan/hw_tags.c | 28 ++++++++++++++++++---------- > mm/kasan/kasan.h | 31 +++++++++++++++++++++++++++---- > mm/kasan/report.c | 2 +- > 5 files changed, 52 insertions(+), 18 deletions(-) > > diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst > index 21dc03bc10a4..8089c559d339 100644 > --- a/Documentation/dev-tools/kasan.rst > +++ b/Documentation/dev-tools/kasan.rst > @@ -194,14 +194,17 @@ additional boot parameters that allow disabling KASAN or controlling features: > > - ``kasan=off`` or ``=on`` controls whether KASAN is enabled (default: ``on``). > > -- ``kasan.mode=sync`` or ``=async`` controls whether KASAN is configured in > - synchronous or asynchronous mode of execution (default: ``sync``). > +- ``kasan.mode=sync``, ``=async`` or ``=asymm`` controls whether KASAN > + is configured in synchronous, asynchronous or asymmetric mode of > + execution (default: ``sync``). > Synchronous mode: a bad access is detected immediately when a tag > check fault occurs. > Asynchronous mode: a bad access detection is delayed. When a tag check > fault occurs, the information is stored in hardware (in the TFSR_EL1 > register for arm64). The kernel periodically checks the hardware and > only reports tag faults during these checks. > + Asymmetric mode: a bad access is detected synchronously on reads and > + asynchronously on writes. > > - ``kasan.stacktrace=off`` or ``=on`` disables or enables alloc and free stack > traces collection (default: ``on``). > diff --git a/lib/test_kasan.c b/lib/test_kasan.c > index 8835e0784578..ebed755ebf34 100644 > --- a/lib/test_kasan.c > +++ b/lib/test_kasan.c > @@ -88,7 +88,7 @@ static void kasan_test_exit(struct kunit *test) > */ > #define KUNIT_EXPECT_KASAN_FAIL(test, expression) do { \ > if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \ > - !kasan_async_mode_enabled()) \ > + kasan_sync_fault_possible()) \ > migrate_disable(); \ > KUNIT_EXPECT_FALSE(test, READ_ONCE(fail_data.report_found)); \ > barrier(); \ > diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c > index 05d1e9460e2e..39e34595f2b4 100644 > --- a/mm/kasan/hw_tags.c > +++ b/mm/kasan/hw_tags.c > @@ -29,6 +29,7 @@ enum kasan_arg_mode { > KASAN_ARG_MODE_DEFAULT, > KASAN_ARG_MODE_SYNC, > KASAN_ARG_MODE_ASYNC, > + KASAN_ARG_MODE_ASYMM, > }; > > enum kasan_arg_stacktrace { > @@ -45,9 +46,9 @@ static enum kasan_arg_stacktrace kasan_arg_stacktrace __ro_after_init; > DEFINE_STATIC_KEY_FALSE(kasan_flag_enabled); > EXPORT_SYMBOL(kasan_flag_enabled); > > -/* Whether the asynchronous mode is enabled. */ > -bool kasan_flag_async __ro_after_init; > -EXPORT_SYMBOL_GPL(kasan_flag_async); > +/* Whether the selected mode is synchronous/asynchronous/asymmetric.*/ > +enum kasan_mode kasan_mode __ro_after_init; > +EXPORT_SYMBOL_GPL(kasan_mode); > > /* Whether to collect alloc/free stack traces. */ > DEFINE_STATIC_KEY_FALSE(kasan_flag_stacktrace); > @@ -69,7 +70,7 @@ static int __init early_kasan_flag(char *arg) > } > early_param("kasan", early_kasan_flag); > > -/* kasan.mode=sync/async */ > +/* kasan.mode=sync/async/asymm */ > static int __init early_kasan_mode(char *arg) > { > if (!arg) > @@ -79,6 +80,8 @@ static int __init early_kasan_mode(char *arg) > kasan_arg_mode = KASAN_ARG_MODE_SYNC; > else if (!strcmp(arg, "async")) > kasan_arg_mode = KASAN_ARG_MODE_ASYNC; > + else if (!strcmp(arg, "asymm")) > + kasan_arg_mode = KASAN_ARG_MODE_ASYMM; > else > return -EINVAL; > > @@ -116,11 +119,13 @@ void kasan_init_hw_tags_cpu(void) > return; > > /* > - * Enable async mode only when explicitly requested through > - * the command line. > + * Enable async or asymm modes only when explicitly requested > + * through the command line. > */ > if (kasan_arg_mode == KASAN_ARG_MODE_ASYNC) > hw_enable_tagging_async(); > + else if (kasan_arg_mode == KASAN_ARG_MODE_ASYMM) > + hw_enable_tagging_asymm(); > else > hw_enable_tagging_sync(); > } > @@ -143,15 +148,18 @@ void __init kasan_init_hw_tags(void) > case KASAN_ARG_MODE_DEFAULT: > /* > * Default to sync mode. > - * Do nothing, kasan_flag_async keeps its default value. > */ kasan_mode = KASAN_MODE_SYNC; then, since the "do nothing" comment is dropped. > - break; > case KASAN_ARG_MODE_SYNC: > - /* Do nothing, kasan_flag_async keeps its default value. */ > + /* Sync mode enabled. */ > + kasan_mode = KASAN_MODE_SYNC; > break; > case KASAN_ARG_MODE_ASYNC: > /* Async mode enabled. */ > - kasan_flag_async = true; > + kasan_mode = KASAN_MODE_ASYNC; > + break; > + case KASAN_ARG_MODE_ASYMM: > + /* Asymm mode enabled. */ > + kasan_mode = KASAN_MODE_ASYMM; > break; > } > > diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h > index 3639e7c8bb98..71b1b5d3d97e 100644 > --- a/mm/kasan/kasan.h > +++ b/mm/kasan/kasan.h > @@ -13,16 +13,29 @@ > #include "../slab.h" > > DECLARE_STATIC_KEY_FALSE(kasan_flag_stacktrace); > -extern bool kasan_flag_async __ro_after_init; > + > +enum kasan_mode { > + KASAN_MODE_SYNC, > + KASAN_MODE_ASYNC, > + KASAN_MODE_ASYMM, > +}; > + > +extern enum kasan_mode kasan_mode __ro_after_init; > > static inline bool kasan_stack_collection_enabled(void) > { > return static_branch_unlikely(&kasan_flag_stacktrace); > } > > -static inline bool kasan_async_mode_enabled(void) > +static inline bool kasan_async_fault_possible(void) > +{ > + return kasan_mode == KASAN_MODE_ASYNC || > + kasan_mode == KASAN_MODE_ASYMM; > +} > + > +static inline bool kasan_sync_fault_possible(void) > { > - return kasan_flag_async; > + return kasan_mode != KASAN_MODE_ASYNC; kasan_mode == KASAN_MODE_SYNC || kasan_mode == KASAN_MODE_ASYMM is more in line with the condition in kasan_async_fault_possible(). > } > #else > > @@ -31,11 +44,16 @@ static inline bool kasan_stack_collection_enabled(void) > return true; > } > > -static inline bool kasan_async_mode_enabled(void) > +static inline bool kasan_async_fault_possible(void) > { > return false; > } > > +static inline bool kasan_sync_fault_possible(void) > +{ > + return true; > +} > + > #endif > > #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) > @@ -287,6 +305,9 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) > #ifndef arch_enable_tagging_async > #define arch_enable_tagging_async() > #endif > +#ifndef arch_enable_tagging_asymm > +#define arch_enable_tagging_asymm() > +#endif > #ifndef arch_force_async_tag_fault > #define arch_force_async_tag_fault() > #endif > @@ -302,6 +323,7 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) > > #define hw_enable_tagging_sync() arch_enable_tagging_sync() > #define hw_enable_tagging_async() arch_enable_tagging_async() > +#define hw_enable_tagging_asymm() arch_enable_tagging_asymm() > #define hw_force_async_tag_fault() arch_force_async_tag_fault() > #define hw_get_random_tag() arch_get_random_tag() > #define hw_get_mem_tag(addr) arch_get_mem_tag(addr) > @@ -312,6 +334,7 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) > > #define hw_enable_tagging_sync() > #define hw_enable_tagging_async() > +#define hw_enable_tagging_asymm() > > #endif /* CONFIG_KASAN_HW_TAGS */ > > diff --git a/mm/kasan/report.c b/mm/kasan/report.c > index 884a950c7026..9da071ad930c 100644 > --- a/mm/kasan/report.c > +++ b/mm/kasan/report.c > @@ -112,7 +112,7 @@ static void start_report(unsigned long *flags) > > static void end_report(unsigned long *flags, unsigned long addr) > { > - if (!kasan_async_mode_enabled()) > + if (!kasan_async_fault_possible()) > trace_error_report_end(ERROR_DETECTOR_KASAN, addr); > pr_err("==================================================================\n"); > add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -- > 2.33.0 > With the mentioned changes: Reviewed-by: Andrey Konovalov From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0FC6FC433EF for ; Wed, 6 Oct 2021 23:08:51 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C1646610CC for ; Wed, 6 Oct 2021 23:08:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org C1646610CC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; 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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org .On Wed, Oct 6, 2021 at 5:48 PM Vincenzo Frascino wrote: > > Architectures supported by KASAN_HW_TAGS can provide an asymmetric mode > of execution. On an MTE enabled arm64 hw for example this can be > identified with the asymmetric tagging mode of execution. In particular, > when such a mode is present, the CPU triggers a fault on a tag mismatch > during a load operation and asynchronously updates a register when a tag > mismatch is detected during a store operation. > > Extend the KASAN HW execution mode kernel command line parameter to > support asymmetric mode. > > Cc: Dmitry Vyukov > Cc: Andrey Ryabinin > Cc: Alexander Potapenko > Cc: Andrey Konovalov > Signed-off-by: Vincenzo Frascino > Reviewed-by: Catalin Marinas > --- > Documentation/dev-tools/kasan.rst | 7 +++++-- > lib/test_kasan.c | 2 +- > mm/kasan/hw_tags.c | 28 ++++++++++++++++++---------- > mm/kasan/kasan.h | 31 +++++++++++++++++++++++++++---- > mm/kasan/report.c | 2 +- > 5 files changed, 52 insertions(+), 18 deletions(-) > > diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst > index 21dc03bc10a4..8089c559d339 100644 > --- a/Documentation/dev-tools/kasan.rst > +++ b/Documentation/dev-tools/kasan.rst > @@ -194,14 +194,17 @@ additional boot parameters that allow disabling KASAN or controlling features: > > - ``kasan=off`` or ``=on`` controls whether KASAN is enabled (default: ``on``). > > -- ``kasan.mode=sync`` or ``=async`` controls whether KASAN is configured in > - synchronous or asynchronous mode of execution (default: ``sync``). > +- ``kasan.mode=sync``, ``=async`` or ``=asymm`` controls whether KASAN > + is configured in synchronous, asynchronous or asymmetric mode of > + execution (default: ``sync``). > Synchronous mode: a bad access is detected immediately when a tag > check fault occurs. > Asynchronous mode: a bad access detection is delayed. When a tag check > fault occurs, the information is stored in hardware (in the TFSR_EL1 > register for arm64). The kernel periodically checks the hardware and > only reports tag faults during these checks. > + Asymmetric mode: a bad access is detected synchronously on reads and > + asynchronously on writes. > > - ``kasan.stacktrace=off`` or ``=on`` disables or enables alloc and free stack > traces collection (default: ``on``). > diff --git a/lib/test_kasan.c b/lib/test_kasan.c > index 8835e0784578..ebed755ebf34 100644 > --- a/lib/test_kasan.c > +++ b/lib/test_kasan.c > @@ -88,7 +88,7 @@ static void kasan_test_exit(struct kunit *test) > */ > #define KUNIT_EXPECT_KASAN_FAIL(test, expression) do { \ > if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \ > - !kasan_async_mode_enabled()) \ > + kasan_sync_fault_possible()) \ > migrate_disable(); \ > KUNIT_EXPECT_FALSE(test, READ_ONCE(fail_data.report_found)); \ > barrier(); \ > diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c > index 05d1e9460e2e..39e34595f2b4 100644 > --- a/mm/kasan/hw_tags.c > +++ b/mm/kasan/hw_tags.c > @@ -29,6 +29,7 @@ enum kasan_arg_mode { > KASAN_ARG_MODE_DEFAULT, > KASAN_ARG_MODE_SYNC, > KASAN_ARG_MODE_ASYNC, > + KASAN_ARG_MODE_ASYMM, > }; > > enum kasan_arg_stacktrace { > @@ -45,9 +46,9 @@ static enum kasan_arg_stacktrace kasan_arg_stacktrace __ro_after_init; > DEFINE_STATIC_KEY_FALSE(kasan_flag_enabled); > EXPORT_SYMBOL(kasan_flag_enabled); > > -/* Whether the asynchronous mode is enabled. */ > -bool kasan_flag_async __ro_after_init; > -EXPORT_SYMBOL_GPL(kasan_flag_async); > +/* Whether the selected mode is synchronous/asynchronous/asymmetric.*/ > +enum kasan_mode kasan_mode __ro_after_init; > +EXPORT_SYMBOL_GPL(kasan_mode); > > /* Whether to collect alloc/free stack traces. */ > DEFINE_STATIC_KEY_FALSE(kasan_flag_stacktrace); > @@ -69,7 +70,7 @@ static int __init early_kasan_flag(char *arg) > } > early_param("kasan", early_kasan_flag); > > -/* kasan.mode=sync/async */ > +/* kasan.mode=sync/async/asymm */ > static int __init early_kasan_mode(char *arg) > { > if (!arg) > @@ -79,6 +80,8 @@ static int __init early_kasan_mode(char *arg) > kasan_arg_mode = KASAN_ARG_MODE_SYNC; > else if (!strcmp(arg, "async")) > kasan_arg_mode = KASAN_ARG_MODE_ASYNC; > + else if (!strcmp(arg, "asymm")) > + kasan_arg_mode = KASAN_ARG_MODE_ASYMM; > else > return -EINVAL; > > @@ -116,11 +119,13 @@ void kasan_init_hw_tags_cpu(void) > return; > > /* > - * Enable async mode only when explicitly requested through > - * the command line. > + * Enable async or asymm modes only when explicitly requested > + * through the command line. > */ > if (kasan_arg_mode == KASAN_ARG_MODE_ASYNC) > hw_enable_tagging_async(); > + else if (kasan_arg_mode == KASAN_ARG_MODE_ASYMM) > + hw_enable_tagging_asymm(); > else > hw_enable_tagging_sync(); > } > @@ -143,15 +148,18 @@ void __init kasan_init_hw_tags(void) > case KASAN_ARG_MODE_DEFAULT: > /* > * Default to sync mode. > - * Do nothing, kasan_flag_async keeps its default value. > */ kasan_mode = KASAN_MODE_SYNC; then, since the "do nothing" comment is dropped. > - break; > case KASAN_ARG_MODE_SYNC: > - /* Do nothing, kasan_flag_async keeps its default value. */ > + /* Sync mode enabled. */ > + kasan_mode = KASAN_MODE_SYNC; > break; > case KASAN_ARG_MODE_ASYNC: > /* Async mode enabled. */ > - kasan_flag_async = true; > + kasan_mode = KASAN_MODE_ASYNC; > + break; > + case KASAN_ARG_MODE_ASYMM: > + /* Asymm mode enabled. */ > + kasan_mode = KASAN_MODE_ASYMM; > break; > } > > diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h > index 3639e7c8bb98..71b1b5d3d97e 100644 > --- a/mm/kasan/kasan.h > +++ b/mm/kasan/kasan.h > @@ -13,16 +13,29 @@ > #include "../slab.h" > > DECLARE_STATIC_KEY_FALSE(kasan_flag_stacktrace); > -extern bool kasan_flag_async __ro_after_init; > + > +enum kasan_mode { > + KASAN_MODE_SYNC, > + KASAN_MODE_ASYNC, > + KASAN_MODE_ASYMM, > +}; > + > +extern enum kasan_mode kasan_mode __ro_after_init; > > static inline bool kasan_stack_collection_enabled(void) > { > return static_branch_unlikely(&kasan_flag_stacktrace); > } > > -static inline bool kasan_async_mode_enabled(void) > +static inline bool kasan_async_fault_possible(void) > +{ > + return kasan_mode == KASAN_MODE_ASYNC || > + kasan_mode == KASAN_MODE_ASYMM; > +} > + > +static inline bool kasan_sync_fault_possible(void) > { > - return kasan_flag_async; > + return kasan_mode != KASAN_MODE_ASYNC; kasan_mode == KASAN_MODE_SYNC || kasan_mode == KASAN_MODE_ASYMM is more in line with the condition in kasan_async_fault_possible(). > } > #else > > @@ -31,11 +44,16 @@ static inline bool kasan_stack_collection_enabled(void) > return true; > } > > -static inline bool kasan_async_mode_enabled(void) > +static inline bool kasan_async_fault_possible(void) > { > return false; > } > > +static inline bool kasan_sync_fault_possible(void) > +{ > + return true; > +} > + > #endif > > #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) > @@ -287,6 +305,9 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) > #ifndef arch_enable_tagging_async > #define arch_enable_tagging_async() > #endif > +#ifndef arch_enable_tagging_asymm > +#define arch_enable_tagging_asymm() > +#endif > #ifndef arch_force_async_tag_fault > #define arch_force_async_tag_fault() > #endif > @@ -302,6 +323,7 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) > > #define hw_enable_tagging_sync() arch_enable_tagging_sync() > #define hw_enable_tagging_async() arch_enable_tagging_async() > +#define hw_enable_tagging_asymm() arch_enable_tagging_asymm() > #define hw_force_async_tag_fault() arch_force_async_tag_fault() > #define hw_get_random_tag() arch_get_random_tag() > #define hw_get_mem_tag(addr) arch_get_mem_tag(addr) > @@ -312,6 +334,7 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) > > #define hw_enable_tagging_sync() > #define hw_enable_tagging_async() > +#define hw_enable_tagging_asymm() > > #endif /* CONFIG_KASAN_HW_TAGS */ > > diff --git a/mm/kasan/report.c b/mm/kasan/report.c > index 884a950c7026..9da071ad930c 100644 > --- a/mm/kasan/report.c > +++ b/mm/kasan/report.c > @@ -112,7 +112,7 @@ static void start_report(unsigned long *flags) > > static void end_report(unsigned long *flags, unsigned long addr) > { > - if (!kasan_async_mode_enabled()) > + if (!kasan_async_fault_possible()) > trace_error_report_end(ERROR_DETECTOR_KASAN, addr); > pr_err("==================================================================\n"); > add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); > -- > 2.33.0 > With the mentioned changes: Reviewed-by: Andrey Konovalov _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel