Unverified Commit c5b42169 authored by Xianting Tian's avatar Xianting Tian Committed by Palmer Dabbelt
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Documentation: kdump: describe VMCOREINFO export for RISCV64 



The following interrelated definitions and ranges are needed by the
kdump crash tool, which are exported by
"arch/riscv/kernel/crash_core.c":

    VA_BITS,
    PAGE_OFFSET,
    phys_ram_base,
    KERNEL_LINK_ADDR,
    MODULES_VADDR ~ MODULES_END,
    VMALLOC_START ~ VMALLOC_END,
    VMEMMAP_START ~ VMEMMAP_END,

Document these RISCV64 exports above.

Reviewed-by: default avatarBagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: default avatarXianting Tian <xianting.tian@linux.alibaba.com>
Acked-by: default avatarBaoquan He <bhe@redhat.com>
Link: https://lore.kernel.org/r/20221026144208.373504-3-xianting.tian@linux.alibaba.com


[Palmer: wrap commit text]
Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent 649d6b10

Documentation/admin-guide/kdump/vmcoreinfo.rst

+29 −0
Original line number Diff line number Diff line
@@ -595,3 +595,32 @@ X2TLB 
-----



Indicates whether the crashed kernel enabled SH extended mode.



RISCV64

=======



VA_BITS

-------



The maximum number of bits for virtual addresses. Used to compute the

virtual memory ranges.



PAGE_OFFSET

-----------



Indicates the virtual kernel start address of the direct-mapped RAM region.



phys_ram_base

-------------



Indicates the start physical RAM address.



MODULES_VADDR|MODULES_END|VMALLOC_START|VMALLOC_END|VMEMMAP_START|VMEMMAP_END|KERNEL_LINK_ADDR

----------------------------------------------------------------------------------------------



Used to get the correct ranges:



  * MODULES_VADDR ~ MODULES_END : Kernel module space.

  * VMALLOC_START ~ VMALLOC_END : vmalloc() / ioremap() space.

  * VMEMMAP_START ~ VMEMMAP_END : vmemmap space, used for struct page array.

  * KERNEL_LINK_ADDR : start address of Kernel link and BPF