From nobody Sun Dec 14 18:58:33 2025 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 22506153BC3 for ; Fri, 7 Jun 2024 20:22:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717791740; cv=none; b=RRgA9GuU6Wv4bT3pPcDf4vl49djAO8ZfdmW4gKvlT+3I5tleRvcG7q92viLjKiY0uwCu+VMoBDd1dwTiamggvpljLx0IlLSht753+O1jrkeRwgGnpx+dLkOL6JKbdta3WXaLXeenPb50SjHMKnFppvGBhm7geCb0yOZjy4gs+J4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717791740; c=relaxed/simple; bh=CnPSiJoSkTaS4DgxuVepbWdO7rowLFCL7+5optFOhBE=; h=From:To:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=mEwJyXvKejkh+LbUip1cWXghIQX6ToZJTl2yyFKWAkgbE4N0ISkAg2nrNOQXVYAmeKU4MiSYX2aD79QO0VCF0eqlCc+KbY4TwJKR7/4woJ49dI35sVSS4GZkl+R80aB030579qhtENbKFOardCkjZjtAXCaNj9EWxnMghsWEzSI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=jV4r27iO; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=qenheITo; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="jV4r27iO"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="qenheITo" From: Nam Cao DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1717791734; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=y4FmsaK4U8owu4NlSDzmS6G8DVihDPJxkQgSL8xnqno=; b=jV4r27iONhJVERHB641eznAaftrwZ3nE682uV9gC1aGX3evxbgEtI3+I/GGIFZOgjpwiHX jrivhNjIULLbcTEF1ebUWj0KfocGBOpUnJ089SgjLwdKHrT3YqY/Eg0SXgoahKrD73OQPD GIPo3UKx7rqQ8OQfdvFUdf7X8OHayoEhJvPcmX6BDOlSxCWNVz6CkE8p3Fk92DtWshTiPF dt03h8kY0i0/VeSoJX638ThLxRh0Z3R5ck0NRVVs8N5T4i5pkp03gk2RhX4GYCP2ODf4pk b/rBf/p5UzcV/U6PLxXYHL0ZFnOUVb7oknY6vFnqE2fmMzHNT9Mjn98ZwcXy8Q== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1717791734; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=y4FmsaK4U8owu4NlSDzmS6G8DVihDPJxkQgSL8xnqno=; b=qenheITowqvS4kQkmh3FtMet7WUSPFv4Sdzt965PbpQbng2mrMAKUNPxeXEZyrFEa0dnT6 byAMvr7yCjRM4vBg== To: Alexandre Ghiti , Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 7/8] riscv: drop the use of XIP_OFFSET in create_kernel_page_table() Date: Fri, 7 Jun 2024 22:22:12 +0200 Message-Id: <4ea3f222a7eb9f91c04b155ff2e4d3ef19158acc.1717789719.git.namcao@linutronix.de> In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" XIP_OFFSET is the hard-coded offset of writable data section within the kernel. By hard-coding this value, the read-only section of the kernel (which is placed before the writable data section) is restricted in size. As a preparation to remove this hard-coded value entirely, stop using XIP_OFFSET in create_kernel_page_table(). Instead use _sdata and _start to do the same thing. Signed-off-by: Nam Cao Reviewed-by: Alexandre Ghiti --- arch/riscv/mm/init.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 313459329d16..b7b6affd4b79 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -911,7 +911,7 @@ static void __init relocate_kernel(void) static void __init create_kernel_page_table(pgd_t *pgdir, __always_unused bool early) { - uintptr_t va, end_va; + uintptr_t va, start_va, end_va; =20 /* Map the flash resident part */ end_va =3D kernel_map.virt_addr + kernel_map.xiprom_sz; @@ -921,10 +921,11 @@ static void __init create_kernel_page_table(pgd_t *pg= dir, PMD_SIZE, PAGE_KERNEL_EXEC); =20 /* Map the data in RAM */ + start_va =3D kernel_map.virt_addr + (uintptr_t)&_sdata - (uintptr_t)&_sta= rt; end_va =3D kernel_map.virt_addr + kernel_map.size; - for (va =3D kernel_map.virt_addr + XIP_OFFSET; va < end_va; va +=3D PMD_S= IZE) + for (va =3D start_va; va < end_va; va +=3D PMD_SIZE) create_pgd_mapping(pgdir, va, - kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)), + kernel_map.phys_addr + (va - start_va), PMD_SIZE, PAGE_KERNEL); } #else --=20 2.39.2