From nobody Sat Apr 11 07:03:10 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A1377C6FA8E for ; Thu, 2 Mar 2023 05:51:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229817AbjCBFvc (ORCPT ); Thu, 2 Mar 2023 00:51:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44696 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229861AbjCBFu5 (ORCPT ); Thu, 2 Mar 2023 00:50:57 -0500 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D0EF84DE12; Wed, 1 Mar 2023 21:50:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1677736255; x=1709272255; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=zbDdVunyGdhXyhjUE3Gbpn/xbHM27xiNyk5ThtGHdLg=; b=WcuqUjLtgjAOK+DLaIe6uzx5hbjPPIsCCX2YrCUB8e0u/7K0voKg+kxF ODNzVC4/TZbOozJmIc+TMJNSTO/vDAs6j2BUMnsoSdtOD6hENS4uOTasd o/I/TUekjaF7sMBTjFAEcfn9OoxdeRSjBdDB509KktFlY7LZ9pdkHCjuz 8K7kg6tPR/akGB1suwqgfcRaffFcEEX/09hBhEYQwWc8CaFmCRu/LQ6lT JJXASbRrgyrugIAkxZsjR9+lxdDyxe/0f2azVBNYlx36Trkz7ehu1J3CL l4K0bu+L90wcK5RQrjY9rkajrxf/s/67MueRhZlt0PM5CrJhnwkvGPk0H A==; X-IronPort-AV: E=McAfee;i="6500,9779,10636"; a="420887132" X-IronPort-AV: E=Sophos;i="5.98,226,1673942400"; d="scan'208";a="420887132" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Mar 2023 21:50:51 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10636"; a="920530924" X-IronPort-AV: E=Sophos;i="5.98,226,1673942400"; d="scan'208";a="920530924" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga006.fm.intel.com with ESMTP; 01 Mar 2023 21:50:48 -0800 From: Xin Li To: linux-kernel@vger.kernel.org, x86@kernel.org, kvm@vger.kernel.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, peterz@infradead.org, andrew.cooper3@citrix.com, seanjc@google.com, pbonzini@redhat.com, ravi.v.shankar@intel.com Subject: [PATCH v4 17/34] x86/fred: add a page fault entry stub for FRED Date: Wed, 1 Mar 2023 21:24:54 -0800 Message-Id: <20230302052511.1918-18-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230302052511.1918-1-xin3.li@intel.com> References: <20230302052511.1918-1-xin3.li@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: "H. Peter Anvin (Intel)" Add a page fault entry stub for FRED. On a FRED system, the faulting address (CR2) is passed on the stack, to avoid the problem of transient state. Thus we get the page fault address from the stack instead of CR2. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/include/asm/fred.h | 2 ++ arch/x86/mm/fault.c | 20 ++++++++++++++++++-- 2 files changed, 20 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/fred.h b/arch/x86/include/asm/fred.h index 2f337162da73..57affbf80ced 100644 --- a/arch/x86/include/asm/fred.h +++ b/arch/x86/include/asm/fred.h @@ -94,6 +94,8 @@ static __always_inline unsigned long fred_event_data(stru= ct pt_regs *regs) #define DEFINE_FRED_HANDLER(f) noinstr DECLARE_FRED_HANDLER(f) typedef DECLARE_FRED_HANDLER((*fred_handler)); =20 +DECLARE_FRED_HANDLER(fred_exc_page_fault); + #endif /* __ASSEMBLY__ */ =20 #endif /* CONFIG_X86_FRED */ diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index a498ae1fbe66..0f946121de14 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -33,6 +33,7 @@ #include /* kvm_handle_async_pf */ #include /* fixup_vdso_exception() */ #include +#include /* fred_event_data() */ =20 #define CREATE_TRACE_POINTS #include @@ -1507,9 +1508,10 @@ handle_page_fault(struct pt_regs *regs, unsigned lon= g error_code, } } =20 -DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault) +static __always_inline void page_fault_common(struct pt_regs *regs, + unsigned int error_code, + unsigned long address) { - unsigned long address =3D read_cr2(); irqentry_state_t state; =20 prefetchw(¤t->mm->mmap_lock); @@ -1556,3 +1558,17 @@ DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault) =20 irqentry_exit(regs, state); } + +DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault) +{ + page_fault_common(regs, error_code, read_cr2()); +} + +#ifdef CONFIG_X86_FRED + +DEFINE_FRED_HANDLER(fred_exc_page_fault) +{ + page_fault_common(regs, regs->orig_ax, fred_event_data(regs)); +} + +#endif /* CONFIG_X86_FRED */ --=20 2.34.1