From patchwork Sun Jul 26 16:04:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11685979 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8CAC0912 for ; Sun, 26 Jul 2020 16:05:56 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 65643206D8 for ; Sun, 26 Jul 2020 16:05:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="t4ZrWUs4"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="kohjCkwv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 65643206D8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=HD36PsNCGllh8Ip2Elh6TAJ2p59D79K/9I/KACqtOM0=; b=t4ZrWUs4r+cZck5hm/pI+j2hG myQllcGqPbgXnaESTAmvVBO1n6Ny8x4PPyz9f7ywxv+oCtfVd+ubMoH6ks0HWoVqTlklgp1b6te2j 1J7SdkrQpRCjp5P4FRlzzJxs6JNmgOWEG/IxknBOGTExW62UHKiPzmdFHhggP4EQrTPPvkruQlTqD Ig0XcSI1f6OhwfMsEreYUxZCb+l82ItbfhKudmAjyLCcbwqGUvv09NApvO+RZmInntc3QQVy8gApG TjIT4h7q7r13KafECi9r/F658s+n4L7feouSqOwvacBT9ROZzbZMb9sbZpV1W8/SsdTJgC6EnNw3j c8qQSea3g==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jzj8R-0003wA-GA; Sun, 26 Jul 2020 16:04:23 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jzj8G-0003sw-0O for linux-arm-kernel@merlin.infradead.org; Sun, 26 Jul 2020 16:04:12 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=Qgxj/loCE+O6wxKk/eqjrsxG348MHNKY89kEnscKvrM=; b=kohjCkwvuA7bxnRm6vGl5H2oKA GzAu5e2DedmqSrCUCxMa2wVzikiqeFhOAl7DopN5IIIPZlxSBnMNN1s+aIJdy4r4w128g5qlQktZ5 YtdAxg07ilyloUoEIvwAATlsMwEJ2nW7RmE7UbmspjS0dD6kmdr2r9RVAXNyFcrA+yeLf7HHn7MeA oabw8e8mNooy7RXCnSFXymIHpGIym1zjyeQwgy9bn5uUfiWozo8sO8UGDSnNOxX8JYvlai4HlPcaf 0UXci6cy2qYk0tiaI2aLMi1nEhYIefNc0mTYxWPPIcsAX+lmWN71eVWE26/hBWamIXrO4SA/W1fnc 8i9ErYBw==; Received: from [2001:4bb8:18c:2acc:2375:88ff:9f84:118d] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jzj8E-0000Zf-1n; Sun, 26 Jul 2020 16:04:10 +0000 From: Christoph Hellwig To: x86@kernel.org, Jan Kara Subject: [PATCH 3/4] compat: add a compat_need_64bit_alignment_fixup() helper Date: Sun, 26 Jul 2020 18:04:00 +0200 Message-Id: <20200726160401.311569-4-hch@lst.de> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200726160401.311569-1-hch@lst.de> References: <20200726160401.311569-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Add a helper to check if the calling syscall needs a fixup for non-natural 64-bit type alignment in the compat ABI. This will only return true for i386 syscalls on x86_64. Signed-off-by: Christoph Hellwig --- arch/x86/include/asm/compat.h | 1 + include/linux/compat.h | 9 +++++++++ 2 files changed, 10 insertions(+) diff --git a/arch/x86/include/asm/compat.h b/arch/x86/include/asm/compat.h index bf547701f41f87..0e327a01f50fbb 100644 --- a/arch/x86/include/asm/compat.h +++ b/arch/x86/include/asm/compat.h @@ -209,6 +209,7 @@ static inline bool in_compat_syscall(void) return in_32bit_syscall(); } #define in_compat_syscall in_compat_syscall /* override the generic impl */ +#define compat_need_64bit_alignment_fixup in_ia32_syscall #endif struct compat_siginfo; diff --git a/include/linux/compat.h b/include/linux/compat.h index c22a7f1d253b87..afdd44ba3a8869 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -945,6 +945,15 @@ static inline bool in_compat_syscall(void) { return false; } #endif /* CONFIG_COMPAT */ +/* + * Some legacy ABIs like the i386 one use less than natural alignment for 64-bit + * types, and will need special compat treatment for that. Most architectures + * don't need that special handling even for compat syscalls. + */ +#ifndef compat_need_64bit_alignment_fixup +#define compat_need_64bit_alignment_fixup() false +#endif + /* * A pointer passed in from user mode. This should not * be used for syscall parameters, just declare them