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 05E65E7717F for ; Fri, 13 Dec 2024 16:27:59 +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:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=S1rNdYHDYoiCGuHVL3rWEPS5yGZ79mGZop8iOafjBsg=; b=dxTcFF+U2VMr3OyVN3ZT2Idl4T rzkMeKCq0kHLxZlhhacwe5bgIiKEQUpgUdmG++AEHVmkarSjUsvSoX1ldI8XQRawGil8ahbgcYZo0 2263t342As4lrc3jytz+heLet66PUie5onHXabcQzz6nQL6CNIKfzsDuqfgaDVxqNUQZkB/mohgic kjDU8PUBDLBcL7fm7+Xwe8oJObTtoby3hBoTC6qD1F1gIuyIqJFAjBU9OYCsUzOuExKo+TkiIMZWL AO0D6pYHGxDag/lDz7FIybJNWPQoSmOltW7weekGRaWVsNA+gm8eBD8HIK6u7/jvWuTtj0Xs053zZ 4fmoUUkg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tM8W6-00000004P4X-26UU; Fri, 13 Dec 2024 16:27:50 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tM8V2-00000004OvY-0Smt for linux-arm-kernel@lists.infradead.org; Fri, 13 Dec 2024 16:26:45 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 4512D5C6142; Fri, 13 Dec 2024 16:26:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 16AEFC4CED0; Fri, 13 Dec 2024 16:26:41 +0000 (UTC) Date: Fri, 13 Dec 2024 16:26:40 +0000 From: Catalin Marinas To: Mark Brown Cc: Will Deacon , Mark Rutland , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel test robot Subject: Re: [PATCH v2] arm64/signal: Silence sparse warning storing GCSPR_EL0 Message-ID: References: <20241211-arm64-gcs-signal-sparse-v2-1-c22f37216135@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241211-arm64-gcs-signal-sparse-v2-1-c22f37216135@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241213_082644_188309_4E7502E0 X-CRM114-Status: GOOD ( 16.64 ) X-BeenThere: linux-arm-kernel@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-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Dec 11, 2024 at 01:00:35AM +0000, Mark Brown wrote: > diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c > index 14ac6fdb872b9672e4b16a097f1b577aae8dec50..08d51fabdb9d47c848f14c9b25d6be04f109c2ee 100644 > --- a/arch/arm64/kernel/signal.c > +++ b/arch/arm64/kernel/signal.c > @@ -39,7 +39,7 @@ > #ifdef CONFIG_ARM64_GCS > #define GCS_SIGNAL_CAP(addr) (((unsigned long)addr) & GCS_CAP_ADDR_MASK) > > -static bool gcs_signal_cap_valid(u64 addr, u64 val) > +static bool gcs_signal_cap_valid(unsigned long __user *addr, u64 val) > { > return val == GCS_SIGNAL_CAP(addr); > } Another personal preference - addresses should be (unsigned long), pointer to be accessed (... __user *). But we could even scrap this function, there's a single caller to a one-line function. > @@ -1094,15 +1094,15 @@ static int gcs_restore_signal(void) > /* > * Check that the cap is the actual GCS before replacing it. > */ > - if (!gcs_signal_cap_valid((u64)gcspr_el0, cap)) > + if (!gcs_signal_cap_valid(gcspr_el0, cap)) > return -EINVAL; > > /* Invalidate the token to prevent reuse */ > - put_user_gcs(0, (__user void*)gcspr_el0, &ret); > + put_user_gcs(0, gcspr_el0, &ret); > if (ret != 0) > return -EFAULT; > > - write_sysreg_s(gcspr_el0 + 1, SYS_GCSPR_EL0); > + write_sysreg_s((__force u64)(gcspr_el0 + 1), SYS_GCSPR_EL0); > > return 0; > } Looking through the code, do we have a similar problem in gcs_signal_entry()? Or do we rely on sparse ignoring (unsigned long) casts? Whichever way we go, I think we should have consistency between these two functions. -- Catalin