From patchwork Thu Mar 30 11:49:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirill A. Shutemov" X-Patchwork-Id: 669272 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 4D523C761AF for ; Thu, 30 Mar 2023 11:51:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231838AbjC3Lvl (ORCPT ); Thu, 30 Mar 2023 07:51:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231221AbjC3LvV (ORCPT ); Thu, 30 Mar 2023 07:51:21 -0400 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 27E38AF27; Thu, 30 Mar 2023 04:50:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1680177045; x=1711713045; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=xeABudaJnL+acO+dda0KFPliSd+zujBisTvxupxsoaI=; b=h00903An2vdimzfAQUXgMPHeTc9oC/uUr0eBZnMvLJSw9EbesJDxMTCJ IHft2aXCwKsZfOqY8kM60byS+ZYCKQLDrT0Myurlp+Dydg/RniSxkxvxE P6fKACqjEcq20+XWFWJf7lZyTLuNP2B678jkKPnGxwc6YJaFa7ynzynrP 2+hFjnBZBUai+KSCLGUJB0RG+nhMt8LLoPz4KvUV1optfxb4yMIsdo/F7 M3sMdAYRfy41/cdui5WwlMmlUvczzL8dw+9ZBG8kOOtU5iDbHhixGr4iU F8g8weuaq1IYjcPZhAHV1f2TDP2ZCrygzMtenu22bRbyN12l5DvlOEDTH A==; X-IronPort-AV: E=McAfee;i="6600,9927,10664"; a="342756822" X-IronPort-AV: E=Sophos;i="5.98,303,1673942400"; d="scan'208";a="342756822" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Mar 2023 04:50:32 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10664"; a="634856512" X-IronPort-AV: E=Sophos;i="5.98,303,1673942400"; d="scan'208";a="634856512" Received: from ngreburx-mobl.ger.corp.intel.com (HELO box.shutemov.name) ([10.251.209.91]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Mar 2023 04:50:18 -0700 Received: by box.shutemov.name (Postfix, from userid 1000) id 7FDFF1095DF; Thu, 30 Mar 2023 14:50:00 +0300 (+03) From: "Kirill A. Shutemov" To: Borislav Petkov , Andy Lutomirski , Sean Christopherson , Andrew Morton , Joerg Roedel , Ard Biesheuvel Cc: Andi Kleen , Kuppuswamy Sathyanarayanan , David Rientjes , Vlastimil Babka , Tom Lendacky , Thomas Gleixner , Peter Zijlstra , Paolo Bonzini , Ingo Molnar , Dario Faggioli , Dave Hansen , Mike Rapoport , David Hildenbrand , Mel Gorman , marcelo.cerri@canonical.com, tim.gardner@canonical.com, khalid.elmously@canonical.com, philip.cox@canonical.com, aarcange@redhat.com, peterx@redhat.com, x86@kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [PATCHv9 14/14] x86/tdx: Add unaccepted memory support Date: Thu, 30 Mar 2023 14:49:56 +0300 Message-Id: <20230330114956.20342-15-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230330114956.20342-1-kirill.shutemov@linux.intel.com> References: <20230330114956.20342-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org Hookup TDX-specific code to accept memory. Accepting the memory is the same process as converting memory from shared to private: kernel notifies VMM with MAP_GPA hypercall and then accept pages with ACCEPT_PAGE module call. The implementation in core kernel uses tdx_enc_status_changed(). It already used for converting memory to shared and back for I/O transactions. Boot stub provides own implementation of tdx_accept_memory(). It is similar in structure to tdx_enc_status_changed(), but only cares about converting memory to private. Signed-off-by: Kirill A. Shutemov --- arch/x86/Kconfig | 2 + arch/x86/boot/compressed/Makefile | 2 +- arch/x86/boot/compressed/error.c | 19 ++++++ arch/x86/boot/compressed/error.h | 1 + arch/x86/boot/compressed/mem.c | 33 +++++++++- arch/x86/boot/compressed/tdx-shared.c | 2 + arch/x86/boot/compressed/tdx.c | 39 +++++++++++ arch/x86/coco/tdx/Makefile | 2 +- arch/x86/coco/tdx/tdx-shared.c | 95 +++++++++++++++++++++++++++ arch/x86/coco/tdx/tdx.c | 86 +----------------------- arch/x86/include/asm/shared/tdx.h | 2 + arch/x86/include/asm/tdx.h | 2 + arch/x86/mm/unaccepted_memory.c | 9 ++- 13 files changed, 206 insertions(+), 88 deletions(-) create mode 100644 arch/x86/boot/compressed/tdx-shared.c create mode 100644 arch/x86/coco/tdx/tdx-shared.c diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index df21fba77db1..448cd869f0bd 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -884,9 +884,11 @@ config INTEL_TDX_GUEST bool "Intel TDX (Trust Domain Extensions) - Guest Support" depends on X86_64 && CPU_SUP_INTEL depends on X86_X2APIC + depends on EFI_STUB select ARCH_HAS_CC_PLATFORM select X86_MEM_ENCRYPT select X86_MCE + select UNACCEPTED_MEMORY help Support running as a guest under Intel TDX. Without this support, the guest kernel can not boot or run under TDX. diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 74f7adee46ad..71d9f71c13eb 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -106,7 +106,7 @@ ifdef CONFIG_X86_64 endif vmlinux-objs-$(CONFIG_ACPI) += $(obj)/acpi.o -vmlinux-objs-$(CONFIG_INTEL_TDX_GUEST) += $(obj)/tdx.o $(obj)/tdcall.o +vmlinux-objs-$(CONFIG_INTEL_TDX_GUEST) += $(obj)/tdx.o $(obj)/tdx-shared.o $(obj)/tdcall.o vmlinux-objs-$(CONFIG_UNACCEPTED_MEMORY) += $(obj)/bitmap.o $(obj)/find.o $(obj)/mem.o vmlinux-objs-$(CONFIG_EFI) += $(obj)/efi.o diff --git a/arch/x86/boot/compressed/error.c b/arch/x86/boot/compressed/error.c index c881878e56d3..5313c5cb2b80 100644 --- a/arch/x86/boot/compressed/error.c +++ b/arch/x86/boot/compressed/error.c @@ -22,3 +22,22 @@ void error(char *m) while (1) asm("hlt"); } + +/* EFI libstub provides vsnprintf() */ +#ifdef CONFIG_EFI_STUB +void panic(const char *fmt, ...) +{ + static char buf[1024]; + va_list args; + int len; + + va_start(args, fmt); + len = vsnprintf(buf, sizeof(buf), fmt, args); + va_end(args); + + if (len && buf[len - 1] == '\n') + buf[len - 1] = '\0'; + + error(buf); +} +#endif diff --git a/arch/x86/boot/compressed/error.h b/arch/x86/boot/compressed/error.h index 1de5821184f1..86fe33b93715 100644 --- a/arch/x86/boot/compressed/error.h +++ b/arch/x86/boot/compressed/error.h @@ -6,5 +6,6 @@ void warn(char *m); void error(char *m) __noreturn; +void panic(const char *fmt, ...) __noreturn __cold; #endif /* BOOT_COMPRESSED_ERROR_H */ diff --git a/arch/x86/boot/compressed/mem.c b/arch/x86/boot/compressed/mem.c index de858a5180b6..e6b92e822ddd 100644 --- a/arch/x86/boot/compressed/mem.c +++ b/arch/x86/boot/compressed/mem.c @@ -5,6 +5,8 @@ #include "error.h" #include "find.h" #include "math.h" +#include "tdx.h" +#include #define PMD_SHIFT 21 #define PMD_SIZE (_AC(1, UL) << PMD_SHIFT) @@ -12,10 +14,39 @@ extern struct boot_params *boot_params; +/* + * accept_memory() and process_unaccepted_memory() called from EFI stub which + * runs before decompresser and its early_tdx_detect(). + * + * Enumerate TDX directly from the early users. + */ +static bool early_is_tdx_guest(void) +{ + static bool once; + static bool is_tdx; + + if (!IS_ENABLED(CONFIG_INTEL_TDX_GUEST)) + return false; + + if (!once) { + u32 eax, sig[3]; + + cpuid_count(TDX_CPUID_LEAF_ID, 0, &eax, + &sig[0], &sig[2], &sig[1]); + is_tdx = !memcmp(TDX_IDENT, sig, sizeof(sig)); + once = true; + } + + return is_tdx; +} + static inline void __accept_memory(phys_addr_t start, phys_addr_t end) { /* Platform-specific memory-acceptance call goes here */ - error("Cannot accept memory"); + if (early_is_tdx_guest()) + tdx_accept_memory(start, end); + else + error("Cannot accept memory: unknown platform\n"); } /* diff --git a/arch/x86/boot/compressed/tdx-shared.c b/arch/x86/boot/compressed/tdx-shared.c new file mode 100644 index 000000000000..5ac43762fe13 --- /dev/null +++ b/arch/x86/boot/compressed/tdx-shared.c @@ -0,0 +1,2 @@ +#include "error.h" +#include "../../coco/tdx/tdx-shared.c" diff --git a/arch/x86/boot/compressed/tdx.c b/arch/x86/boot/compressed/tdx.c index 918a7606f53c..de1d4a87418d 100644 --- a/arch/x86/boot/compressed/tdx.c +++ b/arch/x86/boot/compressed/tdx.c @@ -3,12 +3,17 @@ #include "../cpuflags.h" #include "../string.h" #include "../io.h" +#include "align.h" #include "error.h" +#include "pgtable_types.h" #include #include #include +#include + +static u64 cc_mask; /* Called from __tdx_hypercall() for unrecoverable failure */ void __tdx_hypercall_failed(void) @@ -16,6 +21,38 @@ void __tdx_hypercall_failed(void) error("TDVMCALL failed. TDX module bug?"); } +static u64 get_cc_mask(void) +{ + struct tdx_module_output out; + unsigned int gpa_width; + + /* + * TDINFO TDX module call is used to get the TD execution environment + * information like GPA width, number of available vcpus, debug mode + * information, etc. More details about the ABI can be found in TDX + * Guest-Host-Communication Interface (GHCI), section 2.4.2 TDCALL + * [TDG.VP.INFO]. + * + * The GPA width that comes out of this call is critical. TDX guests + * can not meaningfully run without it. + */ + if (__tdx_module_call(TDX_GET_INFO, 0, 0, 0, 0, &out)) + error("TDCALL GET_INFO failed (Buggy TDX module!)\n"); + + gpa_width = out.rcx & GENMASK(5, 0); + + /* + * The highest bit of a guest physical address is the "sharing" bit. + * Set it for shared pages and clear it for private pages. + */ + return BIT_ULL(gpa_width - 1); +} + +u64 cc_mkdec(u64 val) +{ + return val & ~cc_mask; +} + static inline unsigned int tdx_io_in(int size, u16 port) { struct tdx_hypercall_args args = { @@ -70,6 +107,8 @@ void early_tdx_detect(void) if (memcmp(TDX_IDENT, sig, sizeof(sig))) return; + cc_mask = get_cc_mask(); + /* Use hypercalls instead of I/O instructions */ pio_ops.f_inb = tdx_inb; pio_ops.f_outb = tdx_outb; diff --git a/arch/x86/coco/tdx/Makefile b/arch/x86/coco/tdx/Makefile index 46c55998557d..2c7dcbf1458b 100644 --- a/arch/x86/coco/tdx/Makefile +++ b/arch/x86/coco/tdx/Makefile @@ -1,3 +1,3 @@ # SPDX-License-Identifier: GPL-2.0 -obj-y += tdx.o tdcall.o +obj-y += tdx.o tdx-shared.o tdcall.o diff --git a/arch/x86/coco/tdx/tdx-shared.c b/arch/x86/coco/tdx/tdx-shared.c new file mode 100644 index 000000000000..ee74f7bbe806 --- /dev/null +++ b/arch/x86/coco/tdx/tdx-shared.c @@ -0,0 +1,95 @@ +#include +#include + +static unsigned long try_accept_one(phys_addr_t start, unsigned long len, + enum pg_level pg_level) +{ + unsigned long accept_size = page_level_size(pg_level); + u64 tdcall_rcx; + u8 page_size; + + if (!IS_ALIGNED(start, accept_size)) + return 0; + + if (len < accept_size) + return 0; + + /* + * Pass the page physical address to the TDX module to accept the + * pending, private page. + * + * Bits 2:0 of RCX encode page size: 0 - 4K, 1 - 2M, 2 - 1G. + */ + switch (pg_level) { + case PG_LEVEL_4K: + page_size = 0; + break; + case PG_LEVEL_2M: + page_size = 1; + break; + case PG_LEVEL_1G: + page_size = 2; + break; + default: + return 0; + } + + tdcall_rcx = start | page_size; + if (__tdx_module_call(TDX_ACCEPT_PAGE, tdcall_rcx, 0, 0, 0, NULL)) + return 0; + + return accept_size; +} + +bool tdx_enc_status_changed_phys(phys_addr_t start, phys_addr_t end, bool enc) +{ + if (!enc) { + /* Set the shared (decrypted) bits: */ + start |= cc_mkdec(0); + end |= cc_mkdec(0); + } + + /* + * Notify the VMM about page mapping conversion. More info about ABI + * can be found in TDX Guest-Host-Communication Interface (GHCI), + * section "TDG.VP.VMCALL" + */ + if (_tdx_hypercall(TDVMCALL_MAP_GPA, start, end - start, 0, 0)) + return false; + + /* private->shared conversion requires only MapGPA call */ + if (!enc) + return true; + + /* + * For shared->private conversion, accept the page using + * TDX_ACCEPT_PAGE TDX module call. + */ + while (start < end) { + unsigned long len = end - start; + unsigned long accept_size; + + /* + * Try larger accepts first. It gives chance to VMM to keep + * 1G/2M Secure EPT entries where possible and speeds up + * process by cutting number of hypercalls (if successful). + */ + + accept_size = try_accept_one(start, len, PG_LEVEL_1G); + if (!accept_size) + accept_size = try_accept_one(start, len, PG_LEVEL_2M); + if (!accept_size) + accept_size = try_accept_one(start, len, PG_LEVEL_4K); + if (!accept_size) + return false; + start += accept_size; + } + + return true; +} + +void tdx_accept_memory(phys_addr_t start, phys_addr_t end) +{ + if (!tdx_enc_status_changed_phys(start, end, true)) + panic("Accepting memory failed: %#llx-%#llx\n", start, end); +} diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c index 9e6557d7514c..1392ebc3b406 100644 --- a/arch/x86/coco/tdx/tdx.c +++ b/arch/x86/coco/tdx/tdx.c @@ -713,46 +713,6 @@ static bool tdx_cache_flush_required(void) return true; } -static unsigned long try_accept_one(phys_addr_t start, unsigned long len, - enum pg_level pg_level) -{ - unsigned long accept_size = page_level_size(pg_level); - u64 tdcall_rcx; - u8 page_size; - - if (!IS_ALIGNED(start, accept_size)) - return 0; - - if (len < accept_size) - return 0; - - /* - * Pass the page physical address to the TDX module to accept the - * pending, private page. - * - * Bits 2:0 of RCX encode page size: 0 - 4K, 1 - 2M, 2 - 1G. - */ - switch (pg_level) { - case PG_LEVEL_4K: - page_size = 0; - break; - case PG_LEVEL_2M: - page_size = 1; - break; - case PG_LEVEL_1G: - page_size = 2; - break; - default: - return 0; - } - - tdcall_rcx = start | page_size; - if (__tdx_module_call(TDX_ACCEPT_PAGE, tdcall_rcx, 0, 0, 0, NULL)) - return 0; - - return accept_size; -} - /* * Inform the VMM of the guest's intent for this physical page: shared with * the VMM or private to the guest. The VMM is expected to change its mapping @@ -761,51 +721,9 @@ static unsigned long try_accept_one(phys_addr_t start, unsigned long len, static bool tdx_enc_status_changed(unsigned long vaddr, int numpages, bool enc) { phys_addr_t start = __pa(vaddr); - phys_addr_t end = __pa(vaddr + numpages * PAGE_SIZE); - - if (!enc) { - /* Set the shared (decrypted) bits: */ - start |= cc_mkdec(0); - end |= cc_mkdec(0); - } - - /* - * Notify the VMM about page mapping conversion. More info about ABI - * can be found in TDX Guest-Host-Communication Interface (GHCI), - * section "TDG.VP.VMCALL" - */ - if (_tdx_hypercall(TDVMCALL_MAP_GPA, start, end - start, 0, 0)) - return false; - - /* private->shared conversion requires only MapGPA call */ - if (!enc) - return true; + phys_addr_t end = __pa(vaddr + numpages * PAGE_SIZE); - /* - * For shared->private conversion, accept the page using - * TDX_ACCEPT_PAGE TDX module call. - */ - while (start < end) { - unsigned long len = end - start; - unsigned long accept_size; - - /* - * Try larger accepts first. It gives chance to VMM to keep - * 1G/2M Secure EPT entries where possible and speeds up - * process by cutting number of hypercalls (if successful). - */ - - accept_size = try_accept_one(start, len, PG_LEVEL_1G); - if (!accept_size) - accept_size = try_accept_one(start, len, PG_LEVEL_2M); - if (!accept_size) - accept_size = try_accept_one(start, len, PG_LEVEL_4K); - if (!accept_size) - return false; - start += accept_size; - } - - return true; + return tdx_enc_status_changed_phys(start, end, enc); } void __init tdx_early_init(void) diff --git a/arch/x86/include/asm/shared/tdx.h b/arch/x86/include/asm/shared/tdx.h index 562b3f4cbde8..3afbba545a0d 100644 --- a/arch/x86/include/asm/shared/tdx.h +++ b/arch/x86/include/asm/shared/tdx.h @@ -92,5 +92,7 @@ struct tdx_module_output { u64 __tdx_module_call(u64 fn, u64 rcx, u64 rdx, u64 r8, u64 r9, struct tdx_module_output *out); +void tdx_accept_memory(phys_addr_t start, phys_addr_t end); + #endif /* !__ASSEMBLY__ */ #endif /* _ASM_X86_SHARED_TDX_H */ diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h index 234197ec17e4..3a7340ad9a4b 100644 --- a/arch/x86/include/asm/tdx.h +++ b/arch/x86/include/asm/tdx.h @@ -50,6 +50,8 @@ bool tdx_early_handle_ve(struct pt_regs *regs); int tdx_mcall_get_report0(u8 *reportdata, u8 *tdreport); +bool tdx_enc_status_changed_phys(phys_addr_t start, phys_addr_t end, bool enc); + #else static inline void tdx_early_init(void) { }; diff --git a/arch/x86/mm/unaccepted_memory.c b/arch/x86/mm/unaccepted_memory.c index a0a58486eb74..a521f8c0987d 100644 --- a/arch/x86/mm/unaccepted_memory.c +++ b/arch/x86/mm/unaccepted_memory.c @@ -6,6 +6,7 @@ #include #include +#include #include /* Protects unaccepted memory bitmap */ @@ -61,7 +62,13 @@ void accept_memory(phys_addr_t start, phys_addr_t end) unsigned long len = range_end - range_start; /* Platform-specific memory-acceptance call goes here */ - panic("Cannot accept memory: unknown platform\n"); + if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST)) { + tdx_accept_memory(range_start * PMD_SIZE, + range_end * PMD_SIZE); + } else { + panic("Cannot accept memory: unknown platform\n"); + } + bitmap_clear(bitmap, range_start, len); } spin_unlock_irqrestore(&unaccepted_memory_lock, flags);