From nobody Sat Feb 7 21:15:36 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7CA6A3112D3 for ; Sun, 25 Jan 2026 05:52:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769320350; cv=none; b=e+PTUvr68gmHVgXgLXhEiBt0SUOx4rphlq/7kVzG0bn8TzqArJSNNuHQvLF5/l+s4PpKXgVVSwaQaQBh7l3Y1/ze/0wXr3ikhDjluZFml3Jy5+5BYkAFazGo8qzR71JkJPirTEecvkzlsoEDzABRIcl/Dsjxeg8rdSICyU9zRqI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769320350; c=relaxed/simple; bh=PxKVuX9dZ+15sduk5orMIw8Ay7DKzlNXmTpCvQ7wsUQ=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version:Content-Type; b=C1zDx4jIu2WBKg10vGjyqTa1QzpqZaSWJgss+U2yQfn+nerigYMAMO0WWfxlxIkiwou5jbHH5SqZGSPN72onrUM4LDCeRIUtp+G2OX+ovdTazm/gUe2AftkIR4zrybXhwxame08zWIgQmH8KoadikqdIPNs79vWemJO3paHqmEs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LVPkNI4I; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LVPkNI4I" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 19099C4CEF1; Sun, 25 Jan 2026 05:52:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1769320350; bh=PxKVuX9dZ+15sduk5orMIw8Ay7DKzlNXmTpCvQ7wsUQ=; h=From:To:Cc:Subject:Date:From; b=LVPkNI4IxN8sOpUhYCBHm3yDqC3gKhu2VZqsWBq1koZQ8R/SIEh/xMeK4TqN5Xf6u 8OjMa2Hq5Xiuemt3wZgZJ7PYqufWDu2gjIF9lOLQOsoiiKLtL/I2f/XTsb7dOhMWU3 y9kThvlEG6UFYh5sc1LX7ogi0ODayomkRolzQtljZksh4PYaR3Jnwou4O7nNkrw2Ir KvM0ehNYoxcZGQsLSPkE9hBXP7JQms8Lu1qCq9KpV7clZ+aR3VYZWH26q1ORwNQyuu Zv/UEA46D8KtgV4/1OLrwjQFwLuJN6FqaLdW0DemiE8KFIOPx+wMcj6/DD3hTnT5Vn tQUnCWu3ryr7w== From: guoren@kernel.org To: paul.walmsley@sifive.com, palmer@dabbelt.com, guoren@kernel.org, alex@ghiti.fr, bjorn@rivosinc.com, alexghiti@rivosinc.com Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH V2] riscv: mm: Fixup no5lvl failure when vaddr is invalid Date: Sun, 25 Jan 2026 00:52:12 -0500 Message-Id: <20260125055212.433163-1-guoren@kernel.org> X-Mailer: git-send-email 2.40.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable From: "Guo Ren (Alibaba DAMO Academy)" Unlike no4lvl, no5lvl still continues detect satp, which requires va=3Dpa mapping. When pa=3D0x800000000000, no5lvl would fail in Sv48 mode due to an illegal VA value of 0x800000000000. So, prevent detecting the satp flow for no5lvl, when vaddr is invalid. Add the is_vaddr_valid() function for checking. Fixes: 26e7aacb83df ("riscv: Allow to downgrade paging mode from the comman= d line") Cc: Alexandre Ghiti Cc: Bj=C3=B6rn T=C3=B6pel Signed-off-by: Guo Ren (Alibaba DAMO Academy) --- Changelog: v2: - Use is_vaddr_valid() instead of simple return. - Don't change the original no5lvl code logic. v1: https://lore.kernel.org/linux-riscv/20260118145441.291302-1-guoren@kernel.o= rg/ --- arch/riscv/mm/init.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index addb8a9305be..bfea9f73e703 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -852,6 +852,27 @@ static void __init set_mmap_rnd_bits_max(void) mmap_rnd_bits_max =3D MMAP_VA_BITS - PAGE_SHIFT - 3; } =20 +static bool __init is_vaddr_valid(unsigned long va) +{ + unsigned long up =3D 0; + + switch (satp_mode) { + case SATP_MODE_39: + up =3D 1UL << 38; + break; + case SATP_MODE_48: + up =3D 1UL << 47; + break; + case SATP_MODE_57: + up =3D 1UL << 56; + break; + default: + return false; + } + + return (va < up) || (va >=3D (ULONG_MAX - up + 1)); +} + /* * There is a simple way to determine if 4-level is supported by the * underlying hardware: establish 1:1 mapping in 4-level page table mode @@ -893,6 +914,9 @@ static __init void set_satp_mode(uintptr_t dtb_pa) set_satp_mode_pmd + PMD_SIZE, PMD_SIZE, PAGE_KERNEL_EXEC); retry: + if (!is_vaddr_valid(set_satp_mode_pmd)) + goto out; + create_pgd_mapping(early_pg_dir, set_satp_mode_pmd, pgtable_l5_enabled ? @@ -915,6 +939,7 @@ static __init void set_satp_mode(uintptr_t dtb_pa) disable_pgtable_l4(); } =20 +out: memset(early_pg_dir, 0, PAGE_SIZE); memset(early_p4d, 0, PAGE_SIZE); memset(early_pud, 0, PAGE_SIZE); --=20 2.40.1