From mboxrd@z Thu Jan 1 00:00:00 1970 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 6698D39FD6; Mon, 21 Oct 2024 11:04:15 +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=1729508655; cv=none; b=BLZUeJnCg8gAcKu2kAEYdlv+Hp9PqCT3oGtCXV1wjr3wsKt0mh5KNCl3wOcQrdKuxGfE0yIrjBm2QjetXnW+KKfk6HXdjfQXzFuN0INlTIS5UEc3qtCq8RWUORgQMFAx/j5g8xe5UQ5RbfLItm/KwnTKZbP4i6anHe5lQxnFM+o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729508655; c=relaxed/simple; bh=V2y7vo9LKGOZ0tWW9XkDgj45tINelaxj5+/uHLJyjvA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=JA9mzSjE8AmlIR3fYIZHZBsYRdb9NKkPR7861Zbho65wdMUI7YGfKIr1+iMaG6thmb7O51XqpAcYG4JQ7KjUSCjj+7x4heUMkru0NDi5IJURwbUU9eXmflGA/Tp7XF6R+qlvwv54hVL8zNnPEfvnHTNolyZ9hywxYtA6kW2Tp8I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XMo0M35g; 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="XMo0M35g" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C431AC4CEC3; Mon, 21 Oct 2024 11:04:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729508655; bh=V2y7vo9LKGOZ0tWW9XkDgj45tINelaxj5+/uHLJyjvA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=XMo0M35gln5n5YBsOzPzLQvm37tYESmeI89JvjV5mKLuiw28JenGK69a1rBEJ2+7+ WsrIZhcviLD3dBhbO9wFY/86/NNMRulS0xI0cMvbM4yU7ZMDldEPlxtFCjAjICToSo kY6SIHL1MEqf0OE9zIVaClb7PcVGvRL1dCmD+EPZ9R/IagMJ2E0krfoC43JJYcIaAA sFig3yBqrwK7HFZrmkW/glJqPb13wRp/1ObO1GfJwY0XrJ+u229Y8BO/CrJDIOAWGo Xl/unMeQAxU1TxeLhI1n+eXkewP4OrdOVr4EJ9nx2QSecGrNDnOUb8wr9ei3XveoN+ tRk5lexWW8cdQ== Date: Mon, 21 Oct 2024 13:04:08 +0200 From: Niklas Cassel To: Ryan Roberts Cc: Andrew Morton , Anshuman Khandual , Ard Biesheuvel , Catalin Marinas , Damien Le Moal , David Hildenbrand , Greg Marsden , Ivan Ivanov , Kalesh Singh , Marc Zyngier , Mark Rutland , Matthias Brugger , Miroslav Benes , Will Deacon , linux-arm-kernel@lists.infradead.org, linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Kees Cook , "Gustavo A. R. Silva" Subject: Re: [RFC PATCH v1 34/57] sata_sil24: Remove PAGE_SIZE compile-time constant assumption Message-ID: References: <20241014105514.3206191-1-ryan.roberts@arm.com> <20241014105912.3207374-1-ryan.roberts@arm.com> <20241014105912.3207374-34-ryan.roberts@arm.com> <7aa84080-6845-496a-a394-30d334632298@arm.com> <2f578256-7e56-491f-a4ca-ad6caa72b7ae@arm.com> Precedence: bulk X-Mailing-List: linux-ide@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2f578256-7e56-491f-a4ca-ad6caa72b7ae@arm.com> On Mon, Oct 21, 2024 at 10:24:37AM +0100, Ryan Roberts wrote: > On 17/10/2024 13:51, Niklas Cassel wrote: > > On Thu, Oct 17, 2024 at 01:42:22PM +0100, Ryan Roberts wrote: (snip) > That said, while investigating this, I've spotted a bug in my change. paddr calculation in sil24_qc_issue() is incorrect since sizeof(*pp->cmd_block) is no longer PAGE_SIZE. Based on feedback in another patch, I'm also converting the BUG_ONs to WARN_ON_ONCEs. Side note: Please wrap you lines to 80 characters max. > > Additional proposed change, which I'll plan to include in the next version: > > ---8<--- > diff --git a/drivers/ata/sata_sil24.c b/drivers/ata/sata_sil24.c > index 85c6382976626..c402bf998c4ee 100644 > --- a/drivers/ata/sata_sil24.c > +++ b/drivers/ata/sata_sil24.c > @@ -257,6 +257,10 @@ union sil24_cmd_block { > struct sil24_atapi_block atapi; > }; > > +#define SIL24_ATA_BLOCK_SIZE struct_size_t(struct sil24_ata_block, sge, SIL24_MAX_SGE) > +#define SIL24_ATAPI_BLOCK_SIZE struct_size_t(struct sil24_atapi_block, sge, SIL24_MAX_SGE) > +#define SIL24_CMD_BLOCK_SIZE max(SIL24_ATA_BLOCK_SIZE, SIL24_ATAPI_BLOCK_SIZE) > + > static const struct sil24_cerr_info { > unsigned int err_mask, action; > const char *desc; > @@ -886,7 +890,7 @@ static unsigned int sil24_qc_issue(struct ata_queued_cmd *qc) > dma_addr_t paddr; > void __iomem *activate; > > - paddr = pp->cmd_block_dma + tag * sizeof(*pp->cmd_block); > + paddr = pp->cmd_block_dma + tag * SIL24_CMD_BLOCK_SIZE; > activate = port + PORT_CMD_ACTIVATE + tag * 8; > > /* > @@ -1192,7 +1196,7 @@ static int sil24_port_start(struct ata_port *ap) > struct device *dev = ap->host->dev; > struct sil24_port_priv *pp; > union sil24_cmd_block *cb; > - size_t cb_size = PAGE_SIZE * SIL24_MAX_CMDS; > + size_t cb_size = SIL24_CMD_BLOCK_SIZE * SIL24_MAX_CMDS; > dma_addr_t cb_dma; > > pp = devm_kzalloc(dev, sizeof(*pp), GFP_KERNEL); > @@ -1265,8 +1269,8 @@ static int sil24_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) > u32 tmp; > > /* union sil24_cmd_block must be PAGE_SIZE */ This comment should probably be rephrased to be more clear then, since like you said sizeof(union sil24_cmd_block) will no longer be PAGE_SIZE. > - BUG_ON(struct_size_t(struct sil24_atapi_block, sge, SIL24_MAX_SGE) != PAGE_SIZE); > - BUG_ON(struct_size_t(struct sil24_ata_block, sge, SIL24_MAX_SGE) > PAGE_SIZE); > + WARN_ON_ONCE(SIL24_ATAPI_BLOCK_SIZE != PAGE_SIZE); > + WARN_ON_ONCE(SIL24_ATA_BLOCK_SIZE != PAGE_SIZE - 16); > > ata_print_version_once(&pdev->dev, DRV_VERSION); > ---8<---