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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) by smtp.lore.kernel.org (Postfix) with ESMTP id 913F2C25B74 for ; Mon, 27 May 2024 16:07:20 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=lqqc+rfk; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4Vp0dg5phVz88Tk for ; Tue, 28 May 2024 01:57:11 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=lqqc+rfk; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=145.40.73.55; helo=sin.source.kernel.org; envelope-from=sashal@kernel.org; receiver=lists.ozlabs.org) Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4Vp0bF6hm4z87n3 for ; Tue, 28 May 2024 01:55:05 +1000 (AEST) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 3323CCE0FF0; Mon, 27 May 2024 15:55:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B4D20C2BBFC; Mon, 27 May 2024 15:55:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1716825304; bh=QyS69jgg7CJB7UMnlbRSwr6HqSkeIzryJsG90rMbXzk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lqqc+rfkhJ940cQdqp/rqwQjarRSggA7BGg5KNVW+Rf5RbGEHpgrFVER3Cv8BXPSF MstHb9f9SITmk1DcFlk8kHonY+kODuKzvQ79sjykEJVa7aKEVXQ6lmc5j0f9ppP3ZH 04VOpakk5pbrVqJVAB/UASYdZ+z6YH4LJJQz858mJ+1FTFSjErP767q0gGgAxoPEn7 QLJskF95y5uV2bcA92qrQrRZAUfoRN0syyhyahIMPTn+Wau9dfLGd6Gxs7NTtb75SC FRtonwudkf2PMMVrwbSjYSNo2XQ1JvAU246rP36VQgQ6OT8sV6T23LzbjMBX2UxqRQ hs5Q+TKmocDeQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 6.8 19/20] powerpc/io: Avoid clang null pointer arithmetic warnings Date: Mon, 27 May 2024 11:53:02 -0400 Message-ID: <20240527155349.3864778-19-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240527155349.3864778-1-sashal@kernel.org> References: <20240527155349.3864778-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.8.11 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sasha Levin , wangkefeng.wang@huawei.com, arnd@arndb.de, bhe@redhat.com, Naresh Kamboju , llvm@lists.linux.dev, stanislav.kinsburskii@gmail.com, nathan@kernel.org, geert@linux-m68k.org, bhelgaas@google.com, linuxppc-dev@lists.ozlabs.org, rppt@kernel.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" From: Michael Ellerman [ Upstream commit 03c0f2c2b2220fc9cf8785cd7b61d3e71e24a366 ] With -Wextra clang warns about pointer arithmetic using a null pointer. When building with CONFIG_PCI=n, that triggers a warning in the IO accessors, eg: In file included from linux/arch/powerpc/include/asm/io.h:672: linux/arch/powerpc/include/asm/io-defs.h:23:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 23 | DEF_PCI_AC_RET(inb, u8, (unsigned long port), (port), pio, port) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ... linux/arch/powerpc/include/asm/io.h:591:53: note: expanded from macro '__do_inb' 591 | #define __do_inb(port) readb((PCI_IO_ADDR)_IO_BASE + port); | ~~~~~~~~~~~~~~~~~~~~~ ^ That is because when CONFIG_PCI=n, _IO_BASE is defined as 0. Although _IO_BASE is defined as plain 0, the cast (PCI_IO_ADDR) converts it to void * before the addition with port happens. Instead the addition can be done first, and then the cast. The resulting value will be the same, but avoids the warning, and also avoids void pointer arithmetic which is apparently non-standard. Reported-by: Naresh Kamboju Closes: https://lore.kernel.org/all/CA+G9fYtEh8zmq8k8wE-8RZwW-Qr927RLTn+KqGnq1F=ptaaNsA@mail.gmail.com Signed-off-by: Michael Ellerman Link: https://msgid.link/20240503075619.394467-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin --- arch/powerpc/include/asm/io.h | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h index 08c550ed49be6..ba2e13bb879dc 100644 --- a/arch/powerpc/include/asm/io.h +++ b/arch/powerpc/include/asm/io.h @@ -585,12 +585,12 @@ __do_out_asm(_rec_outl, "stwbrx") #define __do_inw(port) _rec_inw(port) #define __do_inl(port) _rec_inl(port) #else /* CONFIG_PPC32 */ -#define __do_outb(val, port) writeb(val,(PCI_IO_ADDR)_IO_BASE+port); -#define __do_outw(val, port) writew(val,(PCI_IO_ADDR)_IO_BASE+port); -#define __do_outl(val, port) writel(val,(PCI_IO_ADDR)_IO_BASE+port); -#define __do_inb(port) readb((PCI_IO_ADDR)_IO_BASE + port); -#define __do_inw(port) readw((PCI_IO_ADDR)_IO_BASE + port); -#define __do_inl(port) readl((PCI_IO_ADDR)_IO_BASE + port); +#define __do_outb(val, port) writeb(val,(PCI_IO_ADDR)(_IO_BASE+port)); +#define __do_outw(val, port) writew(val,(PCI_IO_ADDR)(_IO_BASE+port)); +#define __do_outl(val, port) writel(val,(PCI_IO_ADDR)(_IO_BASE+port)); +#define __do_inb(port) readb((PCI_IO_ADDR)(_IO_BASE + port)); +#define __do_inw(port) readw((PCI_IO_ADDR)(_IO_BASE + port)); +#define __do_inl(port) readl((PCI_IO_ADDR)(_IO_BASE + port)); #endif /* !CONFIG_PPC32 */ #ifdef CONFIG_EEH @@ -606,12 +606,12 @@ __do_out_asm(_rec_outl, "stwbrx") #define __do_writesw(a, b, n) _outsw(PCI_FIX_ADDR(a),(b),(n)) #define __do_writesl(a, b, n) _outsl(PCI_FIX_ADDR(a),(b),(n)) -#define __do_insb(p, b, n) readsb((PCI_IO_ADDR)_IO_BASE+(p), (b), (n)) -#define __do_insw(p, b, n) readsw((PCI_IO_ADDR)_IO_BASE+(p), (b), (n)) -#define __do_insl(p, b, n) readsl((PCI_IO_ADDR)_IO_BASE+(p), (b), (n)) -#define __do_outsb(p, b, n) writesb((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) -#define __do_outsw(p, b, n) writesw((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) -#define __do_outsl(p, b, n) writesl((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) +#define __do_insb(p, b, n) readsb((PCI_IO_ADDR)(_IO_BASE+(p)), (b), (n)) +#define __do_insw(p, b, n) readsw((PCI_IO_ADDR)(_IO_BASE+(p)), (b), (n)) +#define __do_insl(p, b, n) readsl((PCI_IO_ADDR)(_IO_BASE+(p)), (b), (n)) +#define __do_outsb(p, b, n) writesb((PCI_IO_ADDR)(_IO_BASE+(p)),(b),(n)) +#define __do_outsw(p, b, n) writesw((PCI_IO_ADDR)(_IO_BASE+(p)),(b),(n)) +#define __do_outsl(p, b, n) writesl((PCI_IO_ADDR)(_IO_BASE+(p)),(b),(n)) #define __do_memset_io(addr, c, n) \ _memset_io(PCI_FIX_ADDR(addr), c, n) -- 2.43.0