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| author |   Chao Fan <fanc.fnst@cn.fujitsu.com> | 2019-01-23 19:08:45 +0800 |
|---|---|---|
| committer |   Borislav Petkov <bp@suse.de> | 2019-02-01 11:52:54 +0100 |
| commit | 3c98e71b42a7d0c14639ccb565ea315f3c887f92 (patch) | |
| tree | bc8b355dd41d9036fb2e67c2126cf24c3435c7cf /arch/x86/boot | |
| parent | x86/boot: Copy kstrtoull() to boot/string.c (diff) | |
| download | linux-dev-3c98e71b42a7d0c14639ccb565ea315f3c887f92.tar.xz linux-dev-3c98e71b42a7d0c14639ccb565ea315f3c887f92.zip | |
x86/boot: Add "acpi_rsdp=" early parsing
KASLR may randomly choose offsets which are located in movable memory
regions resulting in the movable memory becoming immovable.
The ACPI SRAT (System/Static Resource Affinity Table) describes memory
ranges including ranges of memory provided by hot-added memory devices.
In order to access SRAT, one needs the Root System Description Pointer
(RSDP) with which to find the Root/Extended System Description Table
(R/XSDT) which then contains the system description tables of which SRAT
is one of.
In case the RSDP address has been passed on the command line (kexec-ing
a second kernel) parse it from there.
[ bp: Rewrite the commit message and cleanup the code. ]
Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: bhe@redhat.com
Cc: caoj.fnst@cn.fujitsu.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: indou.takao@jp.fujitsu.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kasong@redhat.com
Cc: Kees Cook <keescook@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: msys.mizuma@gmail.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190123110850.12433-3-fanc.fnst@cn.fujitsu.com
Diffstat (limited to 'arch/x86/boot')
| -rw-r--r-- | arch/x86/boot/compressed/acpi.c | 32 | ||||
| -rw-r--r-- | arch/x86/boot/compressed/misc.h | 3 |
2 files changed, 35 insertions, 0 deletions
diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c new file mode 100644 index 000000000000..bacfc4ea35ac --- /dev/null +++ b/arch/x86/boot/compressed/acpi.c @@ -0,0 +1,32 @@ +// SPDX-License-Identifier: GPL-2.0 +#define BOOT_CTYPE_H +#include "misc.h" +#include "error.h" +#include "../string.h" + +#ifdef CONFIG_ACPI + +/* + * Max length of 64-bit hex address string is 19, prefix "0x" + 16 hex + * digits, and '\0' for termination. + */ +#define MAX_ADDR_LEN 19 + +static acpi_physical_address get_acpi_rsdp(void) +{ + acpi_physical_address addr = 0; + +#ifdef CONFIG_KEXEC + char val[MAX_ADDR_LEN] = { }; + int ret; + + ret = cmdline_find_option("acpi_rsdp", val, MAX_ADDR_LEN); + if (ret < 0) + return 0; + + if (kstrtoull(val, 16, &addr)) + return 0; +#endif + return addr; +} +#endif /* CONFIG_ACPI */ diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index a1d5918765f3..764ad50c0119 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -25,6 +25,9 @@ #include <asm/bootparam.h> #include <asm/bootparam_utils.h> +#define BOOT_CTYPE_H +#include <linux/acpi.h> + #define BOOT_BOOT_H #include "../ctype.h" |