From nobody Mon May 25 09:56:46 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 F36D63E120C for ; Mon, 18 May 2026 08:07:15 +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=1779091636; cv=none; b=FX1VV/VMs9PnKPZJGzJVtA9UYSqPLIWzJ2+RPKlLUA+CE5G0Kz/L4uUIo1jF3byl81iE2sOA/ydsckZe5B5Cya2iqyEZ20ec9KvrkXZ1ge06tJMDVwsZAjvJ3jdB9So4wvrPIXH+EjXdh6skQhDKfDpS2xI2xAkfVGuZxo5Jw24= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779091636; c=relaxed/simple; bh=oBZLi+ChKV2BA9z1+gJz0dQZF0z5+WDX6/4ux+xL7Rk=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=p40cbmsfQE2Zr/B0T4a2ow+ITrJvT96257vqE54rQU1WkRQyKiuSnjznGFaPQEgfM3725MUwzqVK25+KPdgGo2K1vGPal0Fo9b+HZ/IcW5/yJ7cj3HAfzyUaUwabL6w4MwX85dl21TQO7SMvq5djXDssPn+RKWYJ0hELQ5R74dw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bCjruGr0; 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="bCjruGr0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 25301C2BCB7; Mon, 18 May 2026 08:07:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1779091635; bh=oBZLi+ChKV2BA9z1+gJz0dQZF0z5+WDX6/4ux+xL7Rk=; h=From:To:Cc:Subject:Date:From; b=bCjruGr0Hgw/E3lW0Bb1+ZUe+OJy9Td9/hzcANEiR+PDw/PuvM5Q4noE7JaQ1ClYb l2/sLSw1UMnRJjtATHMT0nykMYTdnQeVZWIfDgTekRJG6sRdIQBGGvQO0F5aIg6GXB ZCiFJRdcGO+ANAnqRS48eHCQon+FpTeqyRCT4DXJTOtiiYZ/gALZiC0UWpcTCXjjff sJ8C3cCC9ypoYNjKH7saxrUYQXSD7kZUxt6Fwt6EfaJU8PQkUYOyJEc0ZMhhbP51y3 elRC782nxHAWXXOS/m5PEv8gomZ6DDQ8JGHXXK06QzW/XCDtUJBFwTJRA7gPmk/kB5 a566GAZ3/G8Gw== From: Guo Ren To: guoren@kernel.org, gaohan@iscas.ac.cn, wangruikang@iscas.ac.cn Cc: alex@ghiti.fr, alexghiti@rivosinc.com, bjorn@kernel.org, bjorn@rivosinc.com, cuiyunhui@bytedance.com, fangyu.yu@linux.alibaba.com, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, palmer@dabbelt.com, pjw@kernel.org, samuel.holland@sifive.com, Chen Pei Subject: [PATCH V3] riscv: mm: Fixup no5lvl failure when vaddr is invalid Date: Mon, 18 May 2026 08:06:46 +0000 Message-ID: <20260518080646.1278708-1-guoren@kernel.org> X-Mailer: git-send-email 2.43.0 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 Tested-by: Fangyu Yu Tested-by: Chen Pei Signed-off-by: Guo Ren (Alibaba DAMO Academy) --- Changelog: v3: - Add two Tested-by tags. - Rebase on Linux 7.1-rc1. v2: https://lore.kernel.org/linux-riscv/20260125055212.433163-1-guoren@kernel.o= rg/ - 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 decd7df40fa4..fa8d2f6f554b 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -792,6 +792,27 @@ 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 @@ -833,6 +854,9 @@ 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 ? @@ -855,6 +879,7 @@ 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 2.43.0