Re: [PATCH V5 5/6] riscv: crash_core: Export kernel vm layout, phys_ram_base

From: Xianting Tian
Date: Wed Aug 10 2022 - 08:00:44 EST



在 2022/8/10 上午5:20, Conor.Dooley@xxxxxxxxxxxxx 写道:
On 02/08/2022 13:18, Xianting Tian wrote:
riscv: crash_core: Export kernel vm layout, phys_ram_base
Can you please just use RISC-V: for the whole series, my OCD
hates the mix haha.

Sorry, I missed it,  you ever pointed out this poblem in the comments of V3, I will definitely fix the issue in V6.


These infos are needed by the kdump crash tool. Since these values change
from time to time, it is preferable to export them via vmcoreinfo than to
change the crash's code frequently.
This commit description doesn't seem to match the patches at all.
I don't see any exporting happening here at all - this is documenting
The real export code is in 2/6 patch, yes this is the document just describe the exporting contents
the export. Maybe I am just misunderstanding, but this commit message
just doesn't seem to match the change. Secondly, should the subject not
be something like "docs: admin-guide: add riscv crash kernel yada yada"?
the commit log for the file 'Documentation/admin-guide/kdump/vmcoreinfo.rst' is not unified in the commit history of the file. I agree with you 'docs: admin-guide: xxx' is better,  will fix it V6.
Maybe the current subject lime that explains the lack of a review from
the docs maintainer?
yes, it is possible :)

Thanks,
Conor.
For your comments for other patches, I will fix it in v6, thanks

Signed-off-by: Xianting Tian <xianting.tian@xxxxxxxxxxxxxxxxx>
---
.../admin-guide/kdump/vmcoreinfo.rst | 31 +++++++++++++++++++
1 file changed, 31 insertions(+)

diff --git a/Documentation/admin-guide/kdump/vmcoreinfo.rst b/Documentation/admin-guide/kdump/vmcoreinfo.rst
index 8419019b6a88..6b76284a503c 100644
--- a/Documentation/admin-guide/kdump/vmcoreinfo.rst
+++ b/Documentation/admin-guide/kdump/vmcoreinfo.rst
@@ -595,3 +595,34 @@ 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 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
+-----------------------------------------------------------------------------
+KASAN_SHADOW_START|KASAN_SHADOW_END|KERNEL_LINK_ADDR|ADDRESS_SPACE_END
+----------------------------------------------------------------------
+
+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 region, used for struct page array.
+ KASAN_SHADOW_START ~ KASAN_SHADOW_END : kasan shadow space.
+ KERNEL_LINK_ADDR ~ ADDRESS_SPACE_END : Kernel link and BPF space.