From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0BF10C3DA40 for ; Thu, 4 Jul 2024 16:27:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=vjQoz/5CTFM/VYY0zOeSPbxeRzdNCA+DsDOOxwBCxy4=; b=dZstaRxehZ0wUpeTnhBQe9D60t B2n27c8o5/FCPSTefjID/hg0z78QRMRsojpQrVCh8L1ufdCyOkS9Abvi+FLWJe19iD8ji72AM4Dad WejaoBi0tRaL8/GCEKi0QkBimdzIZUiBcjUc+6eDo7mfLQ95N5JYR/FPp9pb+fDsG9pxDctujysRV zD9MHph55eD/dEImKlQTv7IGYBbOSpRZm09TAKb7T4RyawMwsBXHeYIezLeaYoKmKkJsj5o8Rn9Q/ cvKNjZPjCIpe5AurDpwM+PyznxmCgUF3tvJ+YiEKVkxmZfEv1GZ3OCMjGAooPqydCbtP1cHbwsm20 8KMR344Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sPPJH-0000000DqGl-30N3; Thu, 04 Jul 2024 16:27:51 +0000 Received: from s3.sipsolutions.net ([2a01:4f8:242:246e::2] helo=sipsolutions.net) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sPPJF-0000000DqEr-2Naf for linux-um@lists.infradead.org; Thu, 04 Jul 2024 16:27:50 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Content-Type:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; bh=vjQoz/5CTFM/VYY0zOeSPbxeRzdNCA+DsDOOxwBCxy4=; t=1720110469; x=1721320069; b=k7PCn8UmWpg09NwZOxtlYwupwORf+JclG+K3iTaC2ghTxoY QporXxWtaDQI/mIwIisfq8nnZzHqiFaWXvHjOU+SECJZhryyAnZOCjTvIrTHzAOfgvuQ+5E32aJtc V+OfSZdNLmAlF14K+to/6z4BVjTc67B0wiVuam+gJnM5xZ37dNdAXfAORNotS1nORlQi7A1f4ORWo 3+lXVdEK9UR3VYd3bouL0sZ47NPRsvT0xQyvJTcbLZwRkMFgOP+1gT5/kMIsYZUPoH77la2tLNfxp AashoXUibjfqu8tuafUm/nIUmSpdTrtH5FG2sCHnWGknT/ii4N2qaSCt6b1rIDpg==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.97) (envelope-from ) id 1sPPJC-0000000DOu8-2ksy; Thu, 04 Jul 2024 18:27:47 +0200 From: Benjamin Berg To: linux-um@lists.infradead.org Cc: Benjamin Berg Subject: [PATCH v7 3/7] um: Fix stub_start address calculation Date: Thu, 4 Jul 2024 18:27:13 +0200 Message-ID: <20240704162717.1417338-4-benjamin@sipsolutions.net> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240704162717.1417338-1-benjamin@sipsolutions.net> References: <20240704162717.1417338-1-benjamin@sipsolutions.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240704_092749_635723_BE6D76E0 X-CRM114-Status: UNSURE ( 9.43 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.org From: Benjamin Berg The calculation was wrong as it only subtracted one and then rounded down for alignment. However, this is incorrect if host_task_size is not already aligned. This probably worked fine because on 64 bit the host_task_size is bigger than returned by os_get_top_address. Signed-off-by: Benjamin Berg --- arch/um/kernel/um_arch.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c index 8e594cda6d77..25cd2c6d7e95 100644 --- a/arch/um/kernel/um_arch.c +++ b/arch/um/kernel/um_arch.c @@ -328,7 +328,8 @@ int __init linux_main(int argc, char **argv) /* reserve a few pages for the stubs (taking care of data alignment) */ /* align the data portion */ BUILD_BUG_ON(!is_power_of_2(STUB_DATA_PAGES)); - stub_start = (host_task_size - 1) & ~(STUB_DATA_PAGES * PAGE_SIZE - 1); + stub_start = (host_task_size - STUB_DATA_PAGES * PAGE_SIZE) & + ~(STUB_DATA_PAGES * PAGE_SIZE - 1); /* another page for the code portion */ stub_start -= PAGE_SIZE; host_task_size = stub_start; -- 2.45.2