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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 779C2EA7940 for ; Wed, 4 Feb 2026 19:19:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C53B06B0098; Wed, 4 Feb 2026 14:19:54 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C3EC96B0099; Wed, 4 Feb 2026 14:19:54 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B7EEA6B009B; Wed, 4 Feb 2026 14:19:54 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id A73E76B0098 for ; Wed, 4 Feb 2026 14:19:54 -0500 (EST) Received: from smtpin21.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 6A56158355 for ; Wed, 4 Feb 2026 19:19:54 +0000 (UTC) X-FDA: 84407739108.21.D2DF197 Received: from mail-244122.protonmail.ch (mail-244122.protonmail.ch [109.224.244.122]) by imf25.hostedemail.com (Postfix) with ESMTP id 811FAA000F for ; Wed, 4 Feb 2026 19:19:52 +0000 (UTC) Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=pm.me header.s=protonmail3 header.b=PGOowp5R; spf=pass (imf25.hostedemail.com: domain of m.wieczorretman@pm.me designates 109.224.244.122 as permitted sender) smtp.mailfrom=m.wieczorretman@pm.me; dmarc=pass (policy=quarantine) header.from=pm.me ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1770232792; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=8q4FTnyJKL7VL66Fr0/i2+AcAlsSlxe0w17bfcxDbBw=; b=TQ7vgO0TetslcIwfdLLhqtbIuaHM/gvjHctjhADloRdyNZAJxTkUPKDlNkmeRcS+WxOqTW rhkVOK2DR/Y+dj/3HvEC/TSEOB1mL+k51tsU31XMgGC3xjWPFtuPs8IGeVfyk2aAIO1f/a OVCFswYMogoQoxfvglyENl/+iHVXsTE= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=pm.me header.s=protonmail3 header.b=PGOowp5R; spf=pass (imf25.hostedemail.com: domain of m.wieczorretman@pm.me designates 109.224.244.122 as permitted sender) smtp.mailfrom=m.wieczorretman@pm.me; dmarc=pass (policy=quarantine) header.from=pm.me ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1770232792; a=rsa-sha256; cv=none; b=SSf4tF1FsBEiF0zeCub1TOf3WWHpoIEgsfFViEvY5eLefcYVC4eF5SMbBaatlmbDQP/j9a K78JVuuHvQUMOEPBDy9yaVGGOVm3mUMgyFP6ApbbW5t5PAJuqKcCtcFFz+vr6r6IzNnF7Y RzGj6guChpCseKayeuzrdAFa2i3rOOc= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pm.me; s=protonmail3; t=1770232790; x=1770491990; bh=8q4FTnyJKL7VL66Fr0/i2+AcAlsSlxe0w17bfcxDbBw=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector; b=PGOowp5R7D7D1nm1AWYNfyiAzwMYE901S2kF3wzkkIcjTUWmYR3o9oIVzPk5VxS62 Hvzc2nMTA+NmRRx2zX8QleHZtEwfWVF5GhWO/Cmemrz1TqG/UkGUYB4QTc+Cx/A2lY Oy6CGuqqnmcbcAG0H2iRgD0nbF8lyyUp01GO5Mxp/CN6/KjSw3pSjgkQ1M1KjdGKmY 16n6wMepcuWVH3MWl1Z/6IPuOb6LkpfJRfq6gIxhAY8n4Nk6qxFevNtj8B8gjZ1mIk tUilgiuVbGRHbf+dX42Bf0TPfc3zIaS/SagH0xhQf/ib2KR721fi0nHddpzWgSWwCo la8NULeSsAxrw== Date: Wed, 04 Feb 2026 19:19:45 +0000 To: Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Axel Rasmussen , Yuanchu Xie , Wei Xu From: Maciej Wieczor-Retman Cc: m.wieczorretman@pm.me, Maciej Wieczor-Retman , kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v10 04/13] x86/kasan: Add arch specific kasan functions Message-ID: In-Reply-To: References: Feedback-ID: 164464600:user:proton X-Pm-Message-ID: 144eb06d27a67966df17bfcfb2a55167d1a539cb MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Stat-Signature: qgwimoerjur89r7gcze6i9g3rjsjszh7 X-Rspamd-Queue-Id: 811FAA000F X-Rspam-User: X-Rspamd-Server: rspam04 X-HE-Tag: 1770232792-759510 X-HE-Meta: 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 rZkmPHCw EhZWDw0WscnwRxBNGvlbnIdz0yn22Pcn3lalhwCmyOMNsGcE8lCMRwEDvAp2f0YlUgf9WaWf/64fkCFn4HtU5pTy05UB/Mn+bcoHwKPyg706aIRp4DW/zTHwVKZFm81+bWZtf+SA2mEm5c9JzELJBGlrPzT91b7YRbKtiLxmDcrnV6rq0AdfbkQuqjgTnZSipP5LFnR+0jBRlxKTTulh8B5Gr1bGZ2GujQGB+W6tgUoT5/DHTytlr8tIB8lDM747r1wgrTfmvAsSbV/jRtHvQuG9fOukKIx3oQMq6FFcpsWDN01tjIvMRT+/AV4wEds4AtWxReZBHCLVh1HeZC82wod7ctqD26R8fJ4Dd9GeBoluY8NI= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Maciej Wieczor-Retman KASAN's software tag-based mode needs multiple macros/functions to handle tag and pointer interactions - to set, retrieve and reset tags from the top bits of a pointer. Mimic functions currently used by arm64 but change the tag's position to bits [60:57] in the pointer. Signed-off-by: Maciej Wieczor-Retman Reviewed-by: Andrey Ryabinin --- Changelog v9: - Rename KASAN_TAG_BYTE_MASK to KASAN_TAG_BITS_MASK. - Add Andrey Ryabinin's Reviewed-by tag. Changelog v7: - Add KASAN_TAG_BYTE_MASK to avoid circular includes and avoid removing KASAN_TAG_MASK from mmzone.h. - Remove Andrey's Acked-by tag. Changelog v6: - Remove empty line after ifdef CONFIG_KASAN_SW_TAGS - Add ifdef 64 bit to avoid problems in vdso32. - Add Andrey's Acked-by tag. Changelog v4: - Rewrite __tag_set() without pointless casts and make it more readable. Changelog v3: - Reorder functions so that __tag_*() etc are above the arch_kasan_*() ones. - Remove CONFIG_KASAN condition from __tag_set() arch/x86/include/asm/kasan.h | 42 ++++++++++++++++++++++++++++++++++-- include/linux/kasan-tags.h | 2 ++ include/linux/mmzone.h | 2 +- 3 files changed, 43 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/kasan.h b/arch/x86/include/asm/kasan.h index d7e33c7f096b..c868ae734f68 100644 --- a/arch/x86/include/asm/kasan.h +++ b/arch/x86/include/asm/kasan.h @@ -3,6 +3,8 @@ #define _ASM_X86_KASAN_H =20 #include +#include +#include #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL) #define KASAN_SHADOW_SCALE_SHIFT 3 =20 @@ -24,8 +26,43 @@ =09=09=09=09=09=09 KASAN_SHADOW_SCALE_SHIFT))) =20 #ifndef __ASSEMBLER__ +#include +#include +#include + +#ifdef CONFIG_KASAN_SW_TAGS +#define __tag_shifted(tag)=09=09FIELD_PREP(GENMASK_ULL(60, 57), tag) +#define __tag_reset(addr)=09=09(sign_extend64((u64)(addr), 56)) +#define __tag_get(addr)=09=09=09((u8)FIELD_GET(GENMASK_ULL(60, 57), (u64)a= ddr)) +#else +#define __tag_shifted(tag)=09=090UL +#define __tag_reset(addr)=09=09(addr) +#define __tag_get(addr)=09=09=090 +#endif /* CONFIG_KASAN_SW_TAGS */ + +#ifdef CONFIG_64BIT +static inline void *__tag_set(const void *__addr, u8 tag) +{ +=09u64 addr =3D (u64)__addr; + +=09addr &=3D ~__tag_shifted(KASAN_TAG_BITS_MASK); +=09addr |=3D __tag_shifted(tag & KASAN_TAG_BITS_MASK); + +=09return (void *)addr; +} +#else +static inline void *__tag_set(void *__addr, u8 tag) +{ +=09return __addr; +} +#endif + +#define arch_kasan_set_tag(addr, tag)=09__tag_set(addr, tag) +#define arch_kasan_reset_tag(addr)=09__tag_reset(addr) +#define arch_kasan_get_tag(addr)=09__tag_get(addr) =20 #ifdef CONFIG_KASAN + void __init kasan_early_init(void); void __init kasan_init(void); void __init kasan_populate_shadow_for_vaddr(void *va, size_t size, int nid= ); @@ -34,8 +71,9 @@ static inline void kasan_early_init(void) { } static inline void kasan_init(void) { } static inline void kasan_populate_shadow_for_vaddr(void *va, size_t size, =09=09=09=09=09=09 int nid) { } -#endif =20 -#endif +#endif /* CONFIG_KASAN */ + +#endif /* __ASSEMBLER__ */ =20 #endif diff --git a/include/linux/kasan-tags.h b/include/linux/kasan-tags.h index ad5c11950233..36cc4f70674a 100644 --- a/include/linux/kasan-tags.h +++ b/include/linux/kasan-tags.h @@ -10,6 +10,8 @@ #define KASAN_TAG_WIDTH=09=090 #endif =20 +#define KASAN_TAG_BITS_MASK=09((1UL << KASAN_TAG_WIDTH) - 1) + #ifndef KASAN_TAG_KERNEL #define KASAN_TAG_KERNEL=090xFF /* native kernel pointers tag */ #endif diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index fc5d6c88d2f0..72c958cb6f3b 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -1177,7 +1177,7 @@ static inline bool zone_is_empty(const struct zone *z= one) #define NODES_MASK=09=09((1UL << NODES_WIDTH) - 1) #define SECTIONS_MASK=09=09((1UL << SECTIONS_WIDTH) - 1) #define LAST_CPUPID_MASK=09((1UL << LAST_CPUPID_SHIFT) - 1) -#define KASAN_TAG_MASK=09=09((1UL << KASAN_TAG_WIDTH) - 1) +#define KASAN_TAG_MASK=09=09KASAN_TAG_BITS_MASK #define ZONEID_MASK=09=09((1UL << ZONEID_SHIFT) - 1) =20 static inline enum zone_type memdesc_zonenum(memdesc_flags_t flags) --=20 2.53.0