linux-kernel - [PATCH v2 2/9] arm64: efi: Add fake memory support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20220414101314.1250667-3-mawupeng1@huawei.com>
Date:   Thu, 14 Apr 2022 18:13:07 +0800
From:   Wupeng Ma <mawupeng1@...wei.com>
To:     <akpm@...ux-foundation.org>, <catalin.marinas@....com>,
        <will@...nel.org>, <corbet@....net>
CC:     <ardb@...nel.org>, <tglx@...utronix.de>, <mingo@...hat.com>,
        <bp@...en8.de>, <dave.hansen@...ux.intel.com>, <x86@...nel.org>,
        <hpa@...cr.com>, <dvhart@...radead.org>, <andy@...radead.org>,
        <rppt@...nel.org>, <paulmck@...nel.org>, <peterz@...radead.org>,
        <jroedel@...e.de>, <songmuchun@...edance.com>, <macro@...am.me.uk>,
        <frederic@...nel.org>, <W_Armin@....de>, <john.garry@...wei.com>,
        <seanjc@...gle.com>, <tsbogend@...ha.franken.de>,
        <anshuman.khandual@....com>, <chenhuacai@...nel.org>,
        <david@...hat.com>, <gpiccoli@...lia.com>, <mark.rutland@....com>,
        <wangkefeng.wang@...wei.com>, <mawupeng1@...wei.com>,
        <linux-doc@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-efi@...r.kernel.org>, <linux-ia64@...r.kernel.org>,
        <platform-driver-x86@...r.kernel.org>, <linux-mm@...ck.org>
Subject: [PATCH v2 2/9] arm64: efi: Add fake memory support

From: Ma Wupeng <mawupeng1@...wei.com>

Fake memory map is used for faking memory's attribute values.
Commit 0f96a99dab36 ("efi: Add "efi_fake_mem" boot option") introduce the
efi_fake_mem function. Now it can support arm64 with this patch.
For example you can mark 0-6G memory as EFI_MEMORY_MORE_RELIABLE by adding
efi_fake_mem=6G@0:0x10000 in the bootarg. You find more info about
fake memmap in kernel-parameters.txt.

Variable memstart_addr is only confirmed after arm64_memblock_init(). So
efi_fake_memmap() is needed to add after arm64_memblock_init().

Otherwise:

efi_memmap_alloc
   memblock_phys_alloc
     kmemleak_alloc_phys
        kmemleak_alloc(__va(phys), size, min_count, gfp);

this __va() will convert phys to a fault va and lead to a kmemleak error.

Signed-off-by: Ma Wupeng <mawupeng1@...wei.com>
---
 Documentation/admin-guide/kernel-parameters.txt | 2 +-
 arch/arm64/kernel/setup.c                       | 2 ++
 drivers/firmware/efi/Kconfig                    | 2 +-
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 3f1cc5e317ed..ea47c0ba7593 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1357,7 +1357,7 @@
 			you are really sure that your UEFI does sane gc and
 			fulfills the spec otherwise your board may brick.
 
-	efi_fake_mem=	nn[KMG]@ss[KMG]:aa[,nn[KMG]@ss[KMG]:aa,..] [EFI; X86]
+	efi_fake_mem=	nn[KMG]@ss[KMG]:aa[,nn[KMG]@ss[KMG]:aa,..] [EFI; X86; ARM64]
 			Add arbitrary attribute to specific memory range by
 			updating original EFI memory map.
 			Region of memory which aa attribute is added to is
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 3505789cf4bd..daade64889ff 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -344,6 +344,8 @@ void __init __no_sanitize_address setup_arch(char **cmdline_p)
 
 	arm64_memblock_init();
 
+	efi_fake_memmap();
+
 	paging_init();
 
 	acpi_table_upgrade();
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 2c3dac5ecb36..3c91bbd4097a 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -50,7 +50,7 @@ config EFI_RUNTIME_MAP
 
 config EFI_FAKE_MEMMAP
 	bool "Enable EFI fake memory map"
-	depends on EFI && X86
+	depends on EFI && (X86 || ARM64)
 	default n
 	help
 	  Saying Y here will enable "efi_fake_mem" boot option.
-- 
2.18.0.huawei.25