From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EEFAC3264EB for ; Thu, 4 Jun 2026 15:12:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780585941; cv=none; b=DO3Rs1h1K59clz8V3HLjN2E6emNd/hHIxzCdlTSMZFy75qA5Tgiq9Uy5YdHjdXjeQxHGdM8BGz4ZtCyeRB3k6xMdPmfxIOIIBIK4YZoRa0zb80UvCJCo/On+m65U0FJUYPWZhTjpC3LYAuI99E00n8xxaY3ys1F8tylo4M/wvLw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780585941; c=relaxed/simple; bh=cbbbZ59Rp73Q1AhTMmKnNcT40z3aKFchofp70lB/j6s=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=owmIL43SQxf40k7nB8tuLggtJR/+evp2ESco4Fqqd80y97gb1/aYgA2ji798ai0NTUBqQ2gK7dBmwgdrIziJDguarWmjDsrhHg8UqmXH7nlvoKtEHVwKz+ZMb0G3O+MpKYEY4ZDJ6v3U2xsxnssy6EbOf+Y8lRTuucTwZOC/Qlc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--ardb.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=uTlPYD4I; arc=none smtp.client-ip=209.85.128.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--ardb.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="uTlPYD4I" Received: by mail-wm1-f73.google.com with SMTP id 5b1f17b1804b1-490b4d3d3e6so6926625e9.0 for ; Thu, 04 Jun 2026 08:12:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1780585938; x=1781190738; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=bXPIHoC6dhQxYOxBacC2HRb5Z1DiryyTwf/00/NWMZQ=; b=uTlPYD4I5zuGDUWEyMYVb11Jm9PeoZ/Vv7g+JYKurfEqT5+o1bGwZqqjz66fYQsjNe MRTmoyFrp+Qhk+C3SbdhQ6qbrs2RzVjl0V3GJvYIYumnulDGqLbVysTC+dTM7y/0gI/B N1067dLiFDSuDD5GFQcvoPOrsexkLHqsURaDK2UACWl4QSUqQxtZ7GvGokBKVNHwKGti gOlMggPDW3VoWOixxt1XbNlf1obHNLUpvDg3ptAvr8Z6WIF62iIv2JqmWzPysf74ft0S Ee7C+9c3eOr2uEybjBFzkiiwIGc9ndlzuoxa6Lw/gPir6VKip9Xe3sLHrav58mrqiUme 2kSQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780585938; x=1781190738; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=bXPIHoC6dhQxYOxBacC2HRb5Z1DiryyTwf/00/NWMZQ=; b=YdlMzJSaMc9YP+wjjbQ9UuzO07n1eI823/yB55Ca3fqcrVzDQ2kTDlFvmQb/2ARIbI PkJtX5ZgZQw+6gpvlLEvuU/L6j7yFlyg6tgV/16IV68Ai895ujnIQLDFseHIKZ60bOxX SRFoIjKT7ROMrQ3lg9+So8WIQNFH1Jq5lU8fuRzFl9gSF9cdNeMgyRsT0QfFT2FWL5no /OiZA/Fpq9qMiwsDJVSIZPeCxooY8BGHix0ZTDqxWA1kok1VXJhURi+Jxn3OFQwcKV+K u7rcoI5T0Oz4hLLOGm7PPR7mgVmpydiywPRFkW6/Mqp8/uK/CWSbE3Wbd0xXF3VXkUkc lL0g== X-Gm-Message-State: AOJu0YyyV8T6AH2LsyICBm4gqF/MBB65eVf9t6IQCipEBrv9xwc9WuQv JiGyzZSJOkQk6uL/2jvUmQad7j0zXE5M7CrYoXy7Rn6uzPlE95ygRKJ0S54DRAkq6Hstv5v9JQ= = X-Received: from wmqy18.prod.google.com ([2002:a05:600c:3652:b0:490:b027:8bb9]) (user=ardb job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:630f:b0:490:b025:f324 with SMTP id 5b1f17b1804b1-490b60e41a8mr143581645e9.32.1780585938337; Thu, 04 Jun 2026 08:12:18 -0700 (PDT) Date: Thu, 4 Jun 2026 17:11:54 +0200 In-Reply-To: <20260604151151.150377-7-ardb+git@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260604151151.150377-7-ardb+git@google.com> X-Developer-Key: i=ardb@kernel.org; a=openpgp; fpr=F43D03328115A198C90016883D200E9CA6329909 X-Developer-Signature: v=1; a=openpgp-sha256; l=2917; i=ardb@kernel.org; h=from:subject; bh=+nQFwh3CCsb7IAFs5SOeV7aCtFUyymbKVrG/Mwiho9M=; b=owGbwMvMwCVmkMcZplerG8N4Wi2JIUtx6m7dg9qWn6/VJZ78s+l3vpXFFt7VC30979V9nqc9P 1tdomhLRykLgxgXg6yYIovA7L/vdp6eKFXrPEsWZg4rE8gQBi5OAZiIw0dGhrM7xP2fXFe4euWa //b3O56+//xxnfLj+G9zPq77arNLWpSd4b9Xz73Vdi+21bFqc1b76n67W/NR6slK4eM/Y+W2nsr 4eoQXAA== X-Mailer: git-send-email 2.54.0.1032.g2f8565e1d1-goog Message-ID: <20260604151151.150377-9-ardb+git@google.com> Subject: [PATCH v2 2/5] kasan: Move generic KASAN page tables out of BSS too From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, will@kernel.org, catalin.marinas@arm.com, Ard Biesheuvel , Kevin Brodsky , Mark Brown , Marc Zyngier , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , kasan-dev@googlegroups.com Content-Type: text/plain; charset="UTF-8" From: Ard Biesheuvel Make sure that all KASAN page tables are emitted into the .pgtbl section (provided that the arch has one - otherwise, fall back to page aligned BSS) This is needed because BSS itself is no longer accessible via the linear map on arm64. Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Dmitry Vyukov Cc: Vincenzo Frascino Cc: kasan-dev@googlegroups.com Signed-off-by: Ard Biesheuvel --- include/linux/linkage.h | 4 ++++ mm/kasan/init.c | 10 +++++----- 2 files changed, 9 insertions(+), 5 deletions(-) diff --git a/include/linux/linkage.h b/include/linux/linkage.h index b11660b706c5..53fe1f48fd28 100644 --- a/include/linux/linkage.h +++ b/include/linux/linkage.h @@ -39,6 +39,10 @@ #define __page_aligned_data __section(".data..page_aligned") __aligned(PAGE_SIZE) #define __page_aligned_bss __section(".bss..page_aligned") __aligned(PAGE_SIZE) +#ifndef __bss_pgtbl +#define __bss_pgtbl __page_aligned_bss +#endif + /* * For assembly routines. * diff --git a/mm/kasan/init.c b/mm/kasan/init.c index 9c880f607c6a..66a883887987 100644 --- a/mm/kasan/init.c +++ b/mm/kasan/init.c @@ -26,10 +26,10 @@ * - Latter it reused it as zero shadow to cover large ranges of memory * that allowed to access, but not handled by kasan (vmalloc/vmemmap ...). */ -unsigned char kasan_early_shadow_page[PAGE_SIZE] __page_aligned_bss; +unsigned char kasan_early_shadow_page[PAGE_SIZE] __bss_pgtbl; #if CONFIG_PGTABLE_LEVELS > 4 -p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D] __page_aligned_bss; +p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D] __bss_pgtbl; static inline bool kasan_p4d_table(pgd_t pgd) { return pgd_page(pgd) == virt_to_page(lm_alias(kasan_early_shadow_p4d)); @@ -41,7 +41,7 @@ static inline bool kasan_p4d_table(pgd_t pgd) } #endif #if CONFIG_PGTABLE_LEVELS > 3 -pud_t kasan_early_shadow_pud[MAX_PTRS_PER_PUD] __page_aligned_bss; +pud_t kasan_early_shadow_pud[MAX_PTRS_PER_PUD] __bss_pgtbl; static inline bool kasan_pud_table(p4d_t p4d) { return p4d_page(p4d) == virt_to_page(lm_alias(kasan_early_shadow_pud)); @@ -53,7 +53,7 @@ static inline bool kasan_pud_table(p4d_t p4d) } #endif #if CONFIG_PGTABLE_LEVELS > 2 -pmd_t kasan_early_shadow_pmd[MAX_PTRS_PER_PMD] __page_aligned_bss; +pmd_t kasan_early_shadow_pmd[MAX_PTRS_PER_PMD] __bss_pgtbl; static inline bool kasan_pmd_table(pud_t pud) { return pud_page(pud) == virt_to_page(lm_alias(kasan_early_shadow_pmd)); @@ -65,7 +65,7 @@ static inline bool kasan_pmd_table(pud_t pud) } #endif pte_t kasan_early_shadow_pte[MAX_PTRS_PER_PTE + PTE_HWTABLE_PTRS] - __page_aligned_bss; + __bss_pgtbl; static inline bool kasan_pte_table(pmd_t pmd) { -- 2.54.0.1032.g2f8565e1d1-goog