From nobody Fri Dec 19 04:53:34 2025 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 B157ACA0EF2 for ; Tue, 12 Sep 2023 15:32:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236509AbjILPcg (ORCPT ); Tue, 12 Sep 2023 11:32:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49826 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236408AbjILPcK (ORCPT ); Tue, 12 Sep 2023 11:32:10 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A03810E3; Tue, 12 Sep 2023 08:32:06 -0700 (PDT) Date: Tue, 12 Sep 2023 15:32:04 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1694532725; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=K97jYLZQiggbcOskDIL09Azt3us2kUi04HAnPmdVB4o=; b=2F0sir8+6ax7w1bbfdW9Lg53VZyVY67kPQUiJ9ZD0Xv759otJF5jSGxfpi0QX9jhn69tVZ nHKhbuYng4Jtutr1nzsx46J81F0ydQI6JbqLx4l1gf5HMFcZ1aa34vC7EbIbmWAIO/jy3W uiYOOiF0gn7deWlXEDUL5yfoj9/6BiqdJllj4157HrMBelXomH1mIhwAG1NO47ithrCz7g 572mDIocFsQx3MQl0HMhtJ0qht9CDcEaDqVUNBtS1Z5Sv5arOCw/ECPGWtUu8PRstmBOPN xAyM3/Gcjg/gYScTDmjcy1cl+jccROwGfvQR1MRkwpnFHwDRs1ehz0hFNDrLuw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1694532725; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=K97jYLZQiggbcOskDIL09Azt3us2kUi04HAnPmdVB4o=; b=ok6CW6Xiqj6tX7KpdjI3QGVM+QQChDoK3lktM4/OK8/+oPiARCFu70XwqZiaSY75IdBVfi 8+cy+zf7kdrT1zAA== From: "tip-bot2 for Kai Huang" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/tdx] x86/tdx: Skip saving output regs when SEAMCALL fails with VMFailInvalid Cc: Peter Zijlstra , Kai Huang , Dave Hansen , "Kirill A. Shutemov" , x86@kernel.org, linux-kernel@vger.kernel.org MIME-Version: 1.0 Message-ID: <169453272448.27769.14213285124047968939.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the x86/tdx branch of tip: Commit-ID: 03a423d40cb30e0e1cb77a801acb56ddb0bf6f5e Gitweb: https://git.kernel.org/tip/03a423d40cb30e0e1cb77a801acb56ddb= 0bf6f5e Author: Kai Huang AuthorDate: Tue, 15 Aug 2023 23:01:56 +12:00 Committer: Dave Hansen CommitterDate: Mon, 11 Sep 2023 16:32:23 -07:00 x86/tdx: Skip saving output regs when SEAMCALL fails with VMFailInvalid If SEAMCALL fails with VMFailInvalid, the SEAM software (e.g., the TDX module) won't have chance to set any output register. Skip saving the output registers to the structure in this case. Also, as '.Lno_output_struct' is the very last symbol before RET, rename it to '.Lout' to make it short. Opportunistically make the asm directives unindented. Suggested-by: Peter Zijlstra Signed-off-by: Kai Huang Signed-off-by: Dave Hansen Reviewed-by: Kirill A. Shutemov Acked-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/all/704088f5b4d72c7e24084f7f15bd1ac5005b7213.= 1692096753.git.kai.huang%40intel.com --- arch/x86/coco/tdx/tdcall.S | 3 --- arch/x86/virt/vmx/tdx/tdxcall.S | 29 ++++++++++++++++++++--------- 2 files changed, 20 insertions(+), 12 deletions(-) diff --git a/arch/x86/coco/tdx/tdcall.S b/arch/x86/coco/tdx/tdcall.S index 2eca5f4..e5d4b7d 100644 --- a/arch/x86/coco/tdx/tdcall.S +++ b/arch/x86/coco/tdx/tdcall.S @@ -78,10 +78,7 @@ * Return status of TDCALL via RAX. */ SYM_FUNC_START(__tdx_module_call) - FRAME_BEGIN TDX_MODULE_CALL host=3D0 - FRAME_END - RET SYM_FUNC_END(__tdx_module_call) =20 /* diff --git a/arch/x86/virt/vmx/tdx/tdxcall.S b/arch/x86/virt/vmx/tdx/tdxcal= l.S index 49a5435..6bdf6e1 100644 --- a/arch/x86/virt/vmx/tdx/tdxcall.S +++ b/arch/x86/virt/vmx/tdx/tdxcall.S @@ -1,5 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ #include +#include #include =20 /* @@ -18,6 +19,7 @@ * TDX module. */ .macro TDX_MODULE_CALL host:req + FRAME_BEGIN /* * R12 will be used as temporary storage for struct tdx_module_output * pointer. Since R12-R15 registers are not used by TDCALL/SEAMCALL @@ -44,7 +46,7 @@ mov %rsi, %rcx /* Leave input param 2 in RDX */ =20 - .if \host +.if \host seamcall /* * SEAMCALL instruction is essentially a VMExit from VMX root @@ -57,13 +59,10 @@ * This value will never be used as actual SEAMCALL error code as * it is from the Reserved status code class. */ - jnc .Lno_vmfailinvalid - mov $TDX_SEAMCALL_VMFAILINVALID, %rax -.Lno_vmfailinvalid: - - .else + jc .Lseamcall_vmfailinvalid +.else tdcall - .endif +.endif =20 /* * Fetch output pointer from stack to R12 (It is used @@ -80,7 +79,7 @@ * Other registers may contain details of the failure. */ test %r12, %r12 - jz .Lno_output_struct + jz .Lout =20 /* Copy result registers to output struct: */ movq %rcx, TDX_MODULE_rcx(%r12) @@ -90,7 +89,19 @@ movq %r10, TDX_MODULE_r10(%r12) movq %r11, TDX_MODULE_r11(%r12) =20 -.Lno_output_struct: +.Lout: /* Restore the state of R12 register */ pop %r12 + + FRAME_END + RET + +.if \host +.Lseamcall_vmfailinvalid: + mov $TDX_SEAMCALL_VMFAILINVALID, %rax + /* pop the unused output pointer back to %r9 */ + pop %r9 + jmp .Lout +.endif /* \host */ + .endm