From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-180.mta0.migadu.com (out-180.mta0.migadu.com [91.218.175.180]) (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 19F83448D09 for ; Tue, 4 Aug 2026 16:35:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.180 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785861358; cv=none; b=B8k3xaQRaIeiqDGfo2aof+BrLBecCj3YBSe33i/cOWsQnwfnxmdjYa+gDk2xWRvAeGiKqwdRFlIb8ghy+lkxN9FD38y3GoSN/B9LdTZiM1J6/k3wQJPzPwhEPZVQkeFCyb3bykiabwbguPRh9fI/byVgghhoJkWpIeW5IO7cbfg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785861358; c=relaxed/simple; bh=alVHBaNB3yfOlCAD+LQqLNRmPp+xjc2VPXTbtrv72b0=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Q+VsMv3M1qaLjkb1tUp1smt3/o5U1Iv5NbFfVMbnZdGo9FmIm+qS9HB4/wNb7l6aPGoT/CRf7lxKyAPTdYbq5l66Xbj/q6Y/57QKWjLixSYV+bNKHgdE/A0sGNJLmvTwQh+i9m4O8rM86fJRMJzaEOXKVQBlPOA5ctXTB8eCNko= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=X1f0c67i; arc=none smtp.client-ip=91.218.175.180 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="X1f0c67i" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1785861349; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=lx6hM/IBtOU20zd29w7TWTsBWkwl6FtKWAIMWvfnRu0=; b=X1f0c67iFQ/MHEsuc0cDwKH1jlAeiYF87gGlcbE8FuOzPqy6FcaAa5uphmbQ1hjmUa/cfb E/DZVqAKLmTiPbJWZVcTRP4arkkr/xBTeCDXYzrbgsa5SVmDkiVav3xBEODSzix+5VQfCH HDrTDS+d3pjwDeuSpPsMbXwzEracRnE= From: Thorsten Blum To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Thorsten Blum Cc: linux-kernel@vger.kernel.org Subject: [PATCH v4] x86/kaslr: Remove redundant if check in slots_fetch_random() Date: Tue, 4 Aug 2026 18:35:36 +0200 Message-ID: <20260804163536.142495-2-thorsten.blum@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1356; i=thorsten.blum@linux.dev; h=from:subject; bh=alVHBaNB3yfOlCAD+LQqLNRmPp+xjc2VPXTbtrv72b0=; b=owGbwMvMwCUWt7pQ4caZUj3G02pJDFlFIjen69s5pO+ry+T7r5t4bFt80C7D5j0dS8/FFkiGC EW+2Hqio5SFQYyLQVZMkeXBrB8zfEtrKjeZROyEmcPKBDKEgYtTACYSy8HIcPb65x8vk3vYjUUZ +I10tr8wfWe0c9HvB9aGzAYaTVvT7BkZTid2ns8/ckVr6dtty0Vruto8koJUOi6fF9i5KHruHUd 1DgA= X-Developer-Key: i=thorsten.blum@linux.dev; a=openpgp; fpr=1D60735E8AEF3BE473B69D84733678FD8DFEEAD4 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT The loop in slots_fetch_random() either returns the slot address or exits with i == slot_area_index, making the if check redundant. Drop it. Signed-off-by: Thorsten Blum --- Changes in v4: - Drop the change in choose_random_location() - Reword subject and patch description - v3: https://lore.kernel.org/r/20260802093531.7165-2-thorsten.blum@linux.dev/ Changes in v3: - Name commit 8391c73c96f2 that added the check (Boris) - Keep the comment (Boris) - v2: https://lore.kernel.org/r/20260731073933.685882-3-thorsten.blum@linux.dev/ Changes in v2: - Explain why the check in choose_random_location() is redundant (Boris) - Reword subject - v1: https://lore.kernel.org/r/20260714205752.133163-2-thorsten.blum@linux.dev/ --- arch/x86/boot/compressed/kaslr.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 81e21c76cbb8..34ee7700ab85 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -541,8 +541,7 @@ static u64 slots_fetch_random(void) return slot_areas[i].addr + ((u64)slot * CONFIG_PHYSICAL_ALIGN); } - if (i == slot_area_index) - debug_putstr("slots_fetch_random() failed!?\n"); + debug_putstr("slots_fetch_random() failed!?\n"); return 0; }