summaryrefslogtreecommitdiffstats
path: root/arch/x86/include
diff options
context:
space:
mode:
authorDan Williams <dan.j.williams@intel.com>2019-11-07 02:43:26 +0100
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2019-11-07 15:44:23 +0100
commit199c8471761273b7e287914cee968ddf21dfbfe0 (patch)
tree9f99308b4861d2cc74bc1ca61e4c0e3bb5e61943 /arch/x86/include
parentarm/efi: EFI soft reservation to memblock (diff)
downloadlinux-199c8471761273b7e287914cee968ddf21dfbfe0.tar.xz
linux-199c8471761273b7e287914cee968ddf21dfbfe0.zip
x86/efi: Add efi_fake_mem support for EFI_MEMORY_SP
Given that EFI_MEMORY_SP is platform BIOS policy decision for marking memory ranges as "reserved for a specific purpose" there will inevitably be scenarios where the BIOS omits the attribute in situations where it is desired. Unlike other attributes if the OS wants to reserve this memory from the kernel the reservation needs to happen early in init. So early, in fact, that it needs to happen before e820__memblock_setup() which is a pre-requisite for efi_fake_memmap() that wants to allocate memory for the updated table. Introduce an x86 specific efi_fake_memmap_early() that can search for attempts to set EFI_MEMORY_SP via efi_fake_mem and update the e820 table accordingly. The KASLR code that scans the command line looking for user-directed memory reservations also needs to be updated to consider "efi_fake_mem=nn@ss:0x40000" requests. Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'arch/x86/include')
-rw-r--r--arch/x86/include/asm/efi.h8
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 45f853bce869..d028e9acdf1c 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -263,4 +263,12 @@ static inline void efi_reserve_boot_services(void)
}
#endif /* CONFIG_EFI */
+#ifdef CONFIG_EFI_FAKE_MEMMAP
+extern void __init efi_fake_memmap_early(void);
+#else
+static inline void efi_fake_memmap_early(void)
+{
+}
+#endif
+
#endif /* _ASM_X86_EFI_H */