From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753776AbeB0Pno (ORCPT ); Tue, 27 Feb 2018 10:43:44 -0500 Received: from mga14.intel.com ([192.55.52.115]:63241 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753930AbeB0Pm2 (ORCPT ); Tue, 27 Feb 2018 10:42:28 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.47,401,1515484800"; d="scan'208";a="20687608" From: "Kirill A. Shutemov" To: Ingo Molnar , x86@kernel.org, Thomas Gleixner , "H. Peter Anvin" Cc: Linus Torvalds , Andy Lutomirski , Cyrill Gorcunov , Borislav Petkov , Andi Kleen , Matthew Wilcox , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [PATCHv2 4/5] x86/boot/compressed/64: Set up trampoline memory Date: Tue, 27 Feb 2018 18:42:16 +0300 Message-Id: <20180227154217.69347-5-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180227154217.69347-1-kirill.shutemov@linux.intel.com> References: <20180227154217.69347-1-kirill.shutemov@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch clears up trampoline memory and copies trampoline code in place. It's not yet used though. Signed-off-by: Kirill A. Shutemov Tested-by: Borislav Petkov --- arch/x86/boot/compressed/head_64.S | 3 ++- arch/x86/boot/compressed/pgtable.h | 9 +++++++++ arch/x86/boot/compressed/pgtable_64.c | 7 +++++++ 3 files changed, 18 insertions(+), 1 deletion(-) diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 8ba0582c65d5..c813cb004056 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -501,8 +501,9 @@ relocated: jmp *%rax .code32 +ENTRY(trampoline_32bit_src) compatible_mode: - /* Setup data and stack segments */ + /* Set up data and stack segments */ movl $__KERNEL_DS, %eax movl %eax, %ds movl %eax, %ss diff --git a/arch/x86/boot/compressed/pgtable.h b/arch/x86/boot/compressed/pgtable.h index 1895f345eb73..cfcb8beeac8f 100644 --- a/arch/x86/boot/compressed/pgtable.h +++ b/arch/x86/boot/compressed/pgtable.h @@ -3,9 +3,18 @@ #define TRAMPOLINE_32BIT_SIZE (2 * PAGE_SIZE) +#define TRAMPOLINE_32BIT_PGTABLE_OFFSET 0 + +#define TRAMPOLINE_32BIT_CODE_OFFSET PAGE_SIZE +#define TRAMPOLINE_32BIT_CODE_SIZE 0x60 + +#define TRAMPOLINE_32BIT_STACK_END TRAMPOLINE_32BIT_SIZE + #ifndef __ASSEMBLY__ extern unsigned long *trampoline_32bit; +extern void trampoline_32bit_src(void *return_ptr); + #endif /* __ASSEMBLY__ */ #endif /* BOOT_COMPRESSED_PAGETABLE_H */ diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c index 01d08d3e3e43..810c2c32d98e 100644 --- a/arch/x86/boot/compressed/pgtable_64.c +++ b/arch/x86/boot/compressed/pgtable_64.c @@ -76,6 +76,13 @@ struct paging_config paging_prepare(void) /* Preserve trampoline memory */ memcpy(trampoline_save, trampoline_32bit, TRAMPOLINE_32BIT_SIZE); + /* Clear trampoline memory first */ + memset(trampoline_32bit, 0, TRAMPOLINE_32BIT_SIZE); + + /* Copy trampoline code in place */ + memcpy(trampoline_32bit + TRAMPOLINE_32BIT_CODE_OFFSET / sizeof(unsigned long), + &trampoline_32bit_src, TRAMPOLINE_32BIT_CODE_SIZE); + return paging_config; } -- 2.16.1