From patchwork Tue Oct 27 13:53:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 312965 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D407FC55178 for ; Tue, 27 Oct 2020 14:22:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9FD14206ED for ; Tue, 27 Oct 2020 14:22:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603808556; bh=rIaUsTsyIDw8OJ5ddlJ2gfLOhA27aUBNYIdzI08QZ5A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=NtaFsOs3jdvVW2Yy/HM7Hsss9XWeogciYd6VD4RHUe6npu0zp9LgbGlLVaNrt5nWa 9yFsxVmUcdA/mPQEg8p1pY4ThvDfymjMHdceCV5eN2ZrAnJtOzYrzzegvpKlypTHj0 wLDKJLr4fdfZnIhYsfaWy9KvRGzVKtahF5QgeYps= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2901324AbgJ0OWf (ORCPT ); Tue, 27 Oct 2020 10:22:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:47188 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2901319AbgJ0OWe (ORCPT ); Tue, 27 Oct 2020 10:22:34 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A4CB7206D4; Tue, 27 Oct 2020 14:22:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603808553; bh=rIaUsTsyIDw8OJ5ddlJ2gfLOhA27aUBNYIdzI08QZ5A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NcwhlIVlOLqyqLTGi1hoB/r+YqMoFBMaYh6a82A5HqIATmFCaXVKWoFZAQaxo5i47 JOpb7wHQz1enf0VJKp7eCwZC5GnlSN09G1j5ptxyC6xJBvpwv7I35a5I3XoNJkJcpv utD4fEPjAary8SNcPTCAA4WjmSbWOuvVmHH4MNdA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Arnd Bergmann , Nathan Chancellor , Miquel Raynal , Sasha Levin Subject: [PATCH 4.19 135/264] mtd: lpddr: fix excessive stack usage with clang Date: Tue, 27 Oct 2020 14:53:13 +0100 Message-Id: <20201027135437.020489048@linuxfoundation.org> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201027135430.632029009@linuxfoundation.org> References: <20201027135430.632029009@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Arnd Bergmann [ Upstream commit 3e1b6469f8324bee5927b063e2aca30d3e56b907 ] Building lpddr2_nvm with clang can result in a giant stack usage in one function: drivers/mtd/lpddr/lpddr2_nvm.c:399:12: error: stack frame size of 1144 bytes in function 'lpddr2_nvm_probe' [-Werror,-Wframe-larger-than=] The problem is that clang decides to build a copy of the mtd_info structure on the stack and then do a memcpy() into the actual version. It shouldn't really do it that way, but it's not strictly a bug either. As a workaround, use a static const version of the structure to assign most of the members upfront and then only set the few members that require runtime knowledge at probe time. Fixes: 96ba9dd65788 ("mtd: lpddr: add driver for LPDDR2-NVM PCM memories") Signed-off-by: Arnd Bergmann Reviewed-by: Nathan Chancellor Acked-by: Miquel Raynal Signed-off-by: Miquel Raynal Link: https://lore.kernel.org/linux-mtd/20200505140136.263461-1-arnd@arndb.de Signed-off-by: Sasha Levin --- drivers/mtd/lpddr/lpddr2_nvm.c | 35 ++++++++++++++++++---------------- 1 file changed, 19 insertions(+), 16 deletions(-) diff --git a/drivers/mtd/lpddr/lpddr2_nvm.c b/drivers/mtd/lpddr/lpddr2_nvm.c index c950c880ad590..90e6cb64db69c 100644 --- a/drivers/mtd/lpddr/lpddr2_nvm.c +++ b/drivers/mtd/lpddr/lpddr2_nvm.c @@ -402,6 +402,17 @@ static int lpddr2_nvm_lock(struct mtd_info *mtd, loff_t start_add, return lpddr2_nvm_do_block_op(mtd, start_add, len, LPDDR2_NVM_LOCK); } +static const struct mtd_info lpddr2_nvm_mtd_info = { + .type = MTD_RAM, + .writesize = 1, + .flags = (MTD_CAP_NVRAM | MTD_POWERUP_LOCK), + ._read = lpddr2_nvm_read, + ._write = lpddr2_nvm_write, + ._erase = lpddr2_nvm_erase, + ._unlock = lpddr2_nvm_unlock, + ._lock = lpddr2_nvm_lock, +}; + /* * lpddr2_nvm driver probe method */ @@ -442,6 +453,7 @@ static int lpddr2_nvm_probe(struct platform_device *pdev) .pfow_base = OW_BASE_ADDRESS, .fldrv_priv = pcm_data, }; + if (IS_ERR(map->virt)) return PTR_ERR(map->virt); @@ -453,22 +465,13 @@ static int lpddr2_nvm_probe(struct platform_device *pdev) return PTR_ERR(pcm_data->ctl_regs); /* Populate mtd_info data structure */ - *mtd = (struct mtd_info) { - .dev = { .parent = &pdev->dev }, - .name = pdev->dev.init_name, - .type = MTD_RAM, - .priv = map, - .size = resource_size(add_range), - .erasesize = ERASE_BLOCKSIZE * pcm_data->bus_width, - .writesize = 1, - .writebufsize = WRITE_BUFFSIZE * pcm_data->bus_width, - .flags = (MTD_CAP_NVRAM | MTD_POWERUP_LOCK), - ._read = lpddr2_nvm_read, - ._write = lpddr2_nvm_write, - ._erase = lpddr2_nvm_erase, - ._unlock = lpddr2_nvm_unlock, - ._lock = lpddr2_nvm_lock, - }; + *mtd = lpddr2_nvm_mtd_info; + mtd->dev.parent = &pdev->dev; + mtd->name = pdev->dev.init_name; + mtd->priv = map; + mtd->size = resource_size(add_range); + mtd->erasesize = ERASE_BLOCKSIZE * pcm_data->bus_width; + mtd->writebufsize = WRITE_BUFFSIZE * pcm_data->bus_width; /* Verify the presence of the device looking for PFOW string */ if (!lpddr2_nvm_pfow_present(map)) {