Linux 커널 보호 메모리와 예약 메모리의 차이점은 무엇입니까? (메모리 매핑 매개변수)

Linux 커널은 memmap매개변수 *)를 사용하여 다양한 사용 사례에 맞게 메모리 영역을 수동으로 지정합니다.

질문: 차이점은 무엇인가요?예약된기억( memmap=nn[KMG]$ss[KMG])과보호받다메모리( memmap=nn[KMG]!ss[KMG])?

즉, 커널은 이를 어떻게 처리하며 언제 사용됩니까?

에 관해서는 예약된 메모리 가 보호된 메모리로 나열되어 있다고 /proc/iomem생각합니다 . 그렇죠?ReservedRAM buffer

*) 텍스트로 가득 차 있지 않고 연결 가능한 좋은 참조 페이지를 찾을 수 없어서 링크를 첨부했습니다.커널 문서:

memmap=exactmap [KNL,X86] Enable setting of an exact
                E820 memory map, as specified by the user.
                Such memmap=exactmap lines can be constructed based on
                BIOS output or other requirements. See the memmap=nn@ss
                option description.

memmap=nn[KMG]@ss[KMG]
                [KNL] Force usage of a specific region of memory.
                Region of memory to be used is from ss to ss+nn.
                If @ss[KMG] is omitted, it is equivalent to mem=nn[KMG],
                which limits max address to nn[KMG].
                Multiple different regions can be specified,
                comma delimited.
                Example:
                        memmap=100M@2G,100M#3G,1G!1024G

memmap=nn[KMG]#ss[KMG]
                [KNL,ACPI] Mark specific memory as ACPI data.
                Region of memory to be marked is from ss to ss+nn.

memmap=nn[KMG]$ss[KMG]
                [KNL,ACPI] Mark specific memory as reserved.
                Region of memory to be reserved is from ss to ss+nn.
                Example: Exclude memory from 0x18690000-0x1869ffff
                         memmap=64K$0x18690000
                         or
                         memmap=0x10000$0x18690000
                Some bootloaders may need an escape character before '$',
                like Grub2, otherwise '$' and the following number
                will be eaten.

memmap=nn[KMG]!ss[KMG]
                [KNL,X86] Mark specific memory as protected.
                Region of memory to be used, from ss to ss+nn.
                The memory region may be marked as e820 type 12 (0xc)
                and is NVDIMM or ADR memory.

memmap=<size>%<offset>-<oldtype>+<newtype>
                [KNL,ACPI] Convert memory within the specified region
                from <oldtype> to <newtype>. If "-<oldtype>" is left
                out, the whole region will be marked as <newtype>,
                even if previously unavailable. If "+<newtype>" is left
                out, matching memory will be removed. Types are
                specified as e820 types, e.g., 1 = RAM, 2 = reserved,
                3 = ACPI, 12 = PRAM.