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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03E54C433F5 for ; Tue, 26 Oct 2021 14:35:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D7FE56115C for ; Tue, 26 Oct 2021 14:35:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236702AbhJZOhh (ORCPT ); Tue, 26 Oct 2021 10:37:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56832 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236696AbhJZOhf (ORCPT ); Tue, 26 Oct 2021 10:37:35 -0400 Received: from mail-pj1-x102b.google.com (mail-pj1-x102b.google.com [IPv6:2607:f8b0:4864:20::102b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 47C10C061745 for ; Tue, 26 Oct 2021 07:35:12 -0700 (PDT) Received: by mail-pj1-x102b.google.com with SMTP id u6-20020a17090a3fc600b001a00250584aso2428568pjm.4 for ; Tue, 26 Oct 2021 07:35:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=tNtCgf+VFHUlZGEKV4gLDOxA8WQx4O5hZ8JXpTy4mIY=; b=Se0gBBeoajcNu+dE+eH19bhUO+AoeRjvw3ioZV0GMOwHpfQrb9ACEdCHxZW/NiW669 FTZYtz2j1zPzdZt72IPx+6Wu7cvdImZtusTpIdzR9bzH0xh5NWrIkCBKrmV/jBX6wh0x hFr9RuEBkhrQk5kzVfxF6SAT+/VGGzOLHryGzXNewuzXANYhl6pNHomwFYsoR68K7BC8 mAYZDBdiUAi7W2qEkiw4I0x4635PNYaLosq6/sht+h3trdv/r1ql/cxwSzGbdewkE/ex X5YtxQK3+tT9vr8HIV1CSWmUniIM3T8lVld1dj4dvMg4ln8Myu10jZ/tPAw6Emq/ie4J Y3hw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=tNtCgf+VFHUlZGEKV4gLDOxA8WQx4O5hZ8JXpTy4mIY=; b=6HWfRtMOM1JswPPGK4aK/aYU7yPwtFsf8yZl5EwMQ4BmoZ9ZSIqmQHR4QQgO6STFzo XZvoFz6J9jozFoZANtusMMFEyT61rdTZVzGa8rMns5qP53cdM3LNj/koKsDM2amRW74c VHi6lqRr6AWzKHCELgha0ZNigL2lASW55VUcjmnZ1OOPQ8MPYjnbmiUwi4W25tY9N6Zg dfAjy6nkddu+OcG3TQ9vhIfM+eBonArTrhIeUACBjXSwbpaEB9lmBV6weNIh2U0BkFXw 0byk0Ucz3MkK/7df6DoOWMnQPo6Rx7dnh17t1cocycqTRyXsaadgaRECVaWtONS3K1vj 2Zdg== X-Gm-Message-State: AOAM531VWjZpmClvIc3Aw3ipizalmgA3XrOVCHdBqQl6EXqXbPP0PZRb nFy29kC8ZAb3RG47biIB/7ylU/WE0l8= X-Google-Smtp-Source: ABdhPJyslmyU+SQde4kWh4CvWVR/sR6JfiAdwQPO0e8ffawXLjiBDLX6NAVhxTmUnCkpLuqn7QdOuw== X-Received: by 2002:a17:90a:a8f:: with SMTP id 15mr29361182pjw.229.1635258911601; Tue, 26 Oct 2021 07:35:11 -0700 (PDT) Received: from localhost ([47.88.5.130]) by smtp.gmail.com with ESMTPSA id m10sm19185184pfk.78.2021.10.26.07.35.10 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 26 Oct 2021 07:35:11 -0700 (PDT) From: Lai Jiangshan To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, Lai Jiangshan , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" Subject: [PATCH V4 28/50] x86/entry: Make paranoid_exit() callable Date: Tue, 26 Oct 2021 22:34:14 +0800 Message-Id: <20211026143436.19071-3-jiangshanlai@gmail.com> X-Mailer: git-send-email 2.19.1.6.gb485710b In-Reply-To: <20211026141420.17138-1-jiangshanlai@gmail.com> References: <20211026141420.17138-1-jiangshanlai@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lai Jiangshan Move the last JMP out of paranoid_exit() and make it callable. Allow paranoid_exit() to be re-written in C later and also allow asm_exc_nmi() to call it to avoid duplicated code. No functional change intended. Signed-off-by: Lai Jiangshan --- arch/x86/entry/entry_64.S | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 79934c5ee9a1..8790bf41edd4 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -472,7 +472,8 @@ SYM_CODE_START(\asmsym) call \cfunc - jmp paranoid_exit + call paranoid_exit + jmp restore_regs_and_return_to_kernel /* Switch to the regular task stack and use the noist entry point */ .Lfrom_usermode_switch_stack_\@: @@ -550,7 +551,8 @@ SYM_CODE_START(\asmsym) * identical to the stack in the IRET frame or the VC fall-back stack, * so it is definitely mapped even with PTI enabled. */ - jmp paranoid_exit + call paranoid_exit + jmp restore_regs_and_return_to_kernel /* Switch to the regular task stack */ .Lfrom_usermode_switch_stack_\@: @@ -581,7 +583,8 @@ SYM_CODE_START(\asmsym) movq $-1, ORIG_RAX(%rsp) /* no syscall to restart */ call \cfunc - jmp paranoid_exit + call paranoid_exit + jmp restore_regs_and_return_to_kernel _ASM_NOKPROBE(\asmsym) SYM_CODE_END(\asmsym) @@ -974,7 +977,7 @@ SYM_CODE_END(paranoid_entry) * Y User space GSBASE, must be restored unconditionally */ SYM_CODE_START_LOCAL(paranoid_exit) - UNWIND_HINT_REGS + UNWIND_HINT_REGS offset=8 /* * The order of operations is important. RESTORE_CR3 requires * kernel GSBASE. @@ -990,16 +993,17 @@ SYM_CODE_START_LOCAL(paranoid_exit) /* With FSGSBASE enabled, unconditionally restore GSBASE */ wrgsbase %rbx - jmp restore_regs_and_return_to_kernel + ret .Lparanoid_exit_checkgs: /* On non-FSGSBASE systems, conditionally do SWAPGS */ testl %ebx, %ebx - jnz restore_regs_and_return_to_kernel + jnz .Lparanoid_exit_done /* We are returning to a context with user GSBASE */ swapgs - jmp restore_regs_and_return_to_kernel +.Lparanoid_exit_done: + ret SYM_CODE_END(paranoid_exit) SYM_CODE_START_LOCAL(error_return) -- 2.19.1.6.gb485710b