From patchwork Tue Jan 11 11:33:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirill A. Shutemov" X-Patchwork-Id: 531259 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 B095DC433FE for ; Tue, 11 Jan 2022 11:33:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349544AbiAKLdR (ORCPT ); Tue, 11 Jan 2022 06:33:17 -0500 Received: from mga04.intel.com ([192.55.52.120]:11112 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349532AbiAKLdO (ORCPT ); Tue, 11 Jan 2022 06:33:14 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1641900794; x=1673436794; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=5dqBdfMq7ze0AdxX7ODzhLdYdgNTaNVDweYGFgnO8Es=; b=fqoEHlDCCQe2QHOEKfRvAvLrrnb97qnJafGb/6KgtNaRISYqwnlAmOno 5NDqUuBvwT349+DIDVrE7bLqfe5cbvlox7hGnyrSyAr2PB6eHG9VG0X2i vmZ0SvpulU2Ik9Kt1I8Mwyhs5YnQO3muRq2cAkFpVlAUhTl/g37W8DjVl BMAf7HQjgaZ676qazBoboKqBG61fQNhO0SLa53+BfeQlvXoX3Drr++O55 lyoGDS9833NSdqOrO7nYSitTAtqA3OsTZpFDYZxoNPFiRyhfe2u077UWw GoOAMQSNOrH3mEd0FSBwjs3ZtmUql5ZtPU00vyW6CQPs2r95smEIEYXXa Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10223"; a="242277580" X-IronPort-AV: E=Sophos;i="5.88,279,1635231600"; d="scan'208";a="242277580" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jan 2022 03:33:14 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,279,1635231600"; d="scan'208";a="472431125" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga003.jf.intel.com with ESMTP; 11 Jan 2022 03:33:08 -0800 Received: by black.fi.intel.com (Postfix, from userid 1000) id 5228C346; Tue, 11 Jan 2022 13:33:19 +0200 (EET) 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 , Varad Gautam , Dario Faggioli , 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: [PATCHv2 4/7] x86/boot/compressed: Handle unaccepted memory Date: Tue, 11 Jan 2022 14:33:11 +0300 Message-Id: <20220111113314.27173-5-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220111113314.27173-1-kirill.shutemov@linux.intel.com> References: <20220111113314.27173-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org Firmware is responsible for accepting memory where compressed kernel image and initrd land. But kernel has to accept memory for decompression buffer: accept memory just before decompression starts. KASLR is allowed to use unaccepted memory for the output buffer. Signed-off-by: Kirill A. Shutemov --- arch/x86/boot/compressed/bitmap.c | 62 ++++++++++++++++++++ arch/x86/boot/compressed/kaslr.c | 14 ++++- arch/x86/boot/compressed/misc.c | 9 +++ arch/x86/boot/compressed/unaccepted_memory.c | 13 ++++ arch/x86/include/asm/unaccepted_memory.h | 2 + 5 files changed, 98 insertions(+), 2 deletions(-) diff --git a/arch/x86/boot/compressed/bitmap.c b/arch/x86/boot/compressed/bitmap.c index bf58b259380a..ba2de61c0823 100644 --- a/arch/x86/boot/compressed/bitmap.c +++ b/arch/x86/boot/compressed/bitmap.c @@ -2,6 +2,48 @@ /* Taken from lib/string.c */ #include +#include +#include + +unsigned long _find_next_bit(const unsigned long *addr1, + const unsigned long *addr2, unsigned long nbits, + unsigned long start, unsigned long invert, unsigned long le) +{ + unsigned long tmp, mask; + + if (unlikely(start >= nbits)) + return nbits; + + tmp = addr1[start / BITS_PER_LONG]; + if (addr2) + tmp &= addr2[start / BITS_PER_LONG]; + tmp ^= invert; + + /* Handle 1st word. */ + mask = BITMAP_FIRST_WORD_MASK(start); + if (le) + mask = swab(mask); + + tmp &= mask; + + start = round_down(start, BITS_PER_LONG); + + while (!tmp) { + start += BITS_PER_LONG; + if (start >= nbits) + return nbits; + + tmp = addr1[start / BITS_PER_LONG]; + if (addr2) + tmp &= addr2[start / BITS_PER_LONG]; + tmp ^= invert; + } + + if (le) + tmp = swab(tmp); + + return min(start + __ffs(tmp), nbits); +} void __bitmap_set(unsigned long *map, unsigned int start, int len) { @@ -22,3 +64,23 @@ void __bitmap_set(unsigned long *map, unsigned int start, int len) *p |= mask_to_set; } } + +void __bitmap_clear(unsigned long *map, unsigned int start, int len) +{ + unsigned long *p = map + BIT_WORD(start); + const unsigned int size = start + len; + int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG); + unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start); + + while (len - bits_to_clear >= 0) { + *p &= ~mask_to_clear; + len -= bits_to_clear; + bits_to_clear = BITS_PER_LONG; + mask_to_clear = ~0UL; + p++; + } + if (len) { + mask_to_clear &= BITMAP_LAST_WORD_MASK(size); + *p &= ~mask_to_clear; + } +} diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 411b268bc0a2..59db90626042 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -725,10 +725,20 @@ process_efi_entries(unsigned long minimum, unsigned long image_size) * but in practice there's firmware where using that memory leads * to crashes. * - * Only EFI_CONVENTIONAL_MEMORY is guaranteed to be free. + * Only EFI_CONVENTIONAL_MEMORY and EFI_UNACCEPTED_MEMORY (if + * supported) are guaranteed to be free. */ - if (md->type != EFI_CONVENTIONAL_MEMORY) + + switch (md->type) { + case EFI_CONVENTIONAL_MEMORY: + break; + case EFI_UNACCEPTED_MEMORY: + if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY)) + break; continue; + default: + continue; + } if (efi_soft_reserve_enabled() && (md->attribute & EFI_MEMORY_SP)) diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index d8373d766672..1e3efd0a8e11 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -18,6 +18,7 @@ #include "../string.h" #include "../voffset.h" #include +#include /* * WARNING!! @@ -446,6 +447,14 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, #endif debug_putstr("\nDecompressing Linux... "); + + if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) && + boot_params->unaccepted_memory) { + debug_putstr("Accepting memory... "); + accept_memory((phys_addr_t)output, + (phys_addr_t)output + needed_size); + } + __decompress(input_data, input_len, NULL, NULL, output, output_len, NULL, error); parse_elf(output); diff --git a/arch/x86/boot/compressed/unaccepted_memory.c b/arch/x86/boot/compressed/unaccepted_memory.c index d8081cde0eed..91db800d5f5e 100644 --- a/arch/x86/boot/compressed/unaccepted_memory.c +++ b/arch/x86/boot/compressed/unaccepted_memory.c @@ -43,3 +43,16 @@ void mark_unaccepted(struct boot_params *params, u64 start, u64 end) bitmap_set((unsigned long *)params->unaccepted_memory, start / PMD_SIZE, (end - start) / PMD_SIZE); } + +void accept_memory(phys_addr_t start, phys_addr_t end) +{ + unsigned long *unaccepted_memory; + unsigned int rs, re; + + unaccepted_memory = (unsigned long *)boot_params->unaccepted_memory; + bitmap_for_each_set_region(unaccepted_memory, rs, re, + start / PMD_SIZE, end / PMD_SIZE) { + __accept_memory(rs * PMD_SIZE, re * PMD_SIZE); + bitmap_clear(unaccepted_memory, rs, re - rs); + } +} diff --git a/arch/x86/include/asm/unaccepted_memory.h b/arch/x86/include/asm/unaccepted_memory.h index cbc24040b853..f1f835d3cd78 100644 --- a/arch/x86/include/asm/unaccepted_memory.h +++ b/arch/x86/include/asm/unaccepted_memory.h @@ -9,4 +9,6 @@ struct boot_params; void mark_unaccepted(struct boot_params *params, u64 start, u64 num); +void accept_memory(phys_addr_t start, phys_addr_t end); + #endif