[PATCH makedumpfile 0/2] Add riscv64 support for makedumpfile

[HAGIO KAZUHITO(萩尾 一仁)]

On 2023/10/07 11:27, Song Shuai wrote:
> 
> 
> 在 2023/10/3 12:22, HAGIO KAZUHITO(萩尾 一仁) 写道:
>> Hi,
>>
>> thank you for the patch.
>>
>> On 2023/09/27 20:18, Song Shuai wrote:
>>> These 2 patches add riscv64 support for makedumpfile:
>>>
>>> Patch1 - Add riscv64 support
>>> ===========================
>>>
>>> This patch adds support for riscv64 in makedumpfile.
>>> It implements the "vtop" for kenrel memory regions
>>> and supports Sv39/Sv48/Sv57 page modes for RV64.
>>
>> Could I have a log of makedumpfile with --message-level 31 option for
>> reference? e.g.
>>     makedumpfile -c -d 31 --message-level 31 vmcore dumpfile > mkdf.log
>>
>> (IIRC the kexec mail list doesn't accept attached files, so please send
>> it off-list.)
> 
> Sorry for the later reply,
> 
> here are the log for the Sv57 and SPARSE_EXTREME kernel:
> 
> https://termbin.com/zcf9:
> 
> and the log for FLATMEM
> 
> https://termbin.com/t89k

Thank you for the information.

> 
>>
>>>
>>>
>>> Patch2 - riscv64: Correct the pfn_start for flatmem
>>> ==================================================
>>>
>>> This patch temporarily fixes a issue of the tests about FLATMEM,
>>> as the commit-msg says:
>>>       To let info->max_mapnr indicte the direct max PFN and then
>>
>> This means "indicate", right?
>>
> Right, would fix it if you're ok with the Patch2.

The patches look good, so applied with fixing it and several indent 
adjustments.

Thanks,
Kazu

> 
>> Thanks,
>> Kazu
>>
>>>       make the kdump header's max_mapnr_64 correct, riscv64 port
>>>       didn't define ARCH_PFN_OFFSET.
>>>       As for FLATMEM type, the pfn region of mem_map_data should
>>>       be adjusted to start from info->phys_base instead of zero.
>>>
>>> Not taking other arches into consideration and test, so I simplely
>>> judge the __riscv64__ instead of ARCH_PFN_OFFSET. Maybe we can 
>>> improve it.
>>>
>>>
>>> Tests
>>> =====
>>>
>>> With these 2 patches, the following tests had passed in RV64 Qemu 
>>> virt machine:
>>>
>>> Preparation:
>>> -----------
>>>
>>> 1. build kernel with FLATMEM and SPARSE memory models
>>> 2. boot kernel with 3 different page-modes by setting nov4l/nov5l in 
>>> cmdline
>>> 3. panic kernel
>>>
>>> Tests:
>>> -----
>>>
>>> 1. create kdump-compressed file via this command
>>>      - `/mnt/mkdf_f -d31 -f -c /proc/vmcore /mnt/dump.file1`
>>>      - or with `--vtop` option to translate some typical addresses 
>>> (like:
>>>        kernel_link_addr, vmalloc_start, page_offset)
>>>
>>> 2. start crash with kdump file and do some VTOPs
>>>
>>>
>>> A test log:
>>> -----------
>>>
>>> # With the Sv57 and SPARSE_EXTREME kernel
>>> # vtop the vmalloc start address -- 0xff20000000000000
>>>
>>>
>>> # /mnt/mkdf_f  --vtop 0xff20000000000000 -d31 -f --non-mmap -c 
>>> /proc/vmcore /mnt/dump.file1
>>>
>>> Translating virtual address ff20000000000000 to physical address.
>>> VIRTUAL           PHYSICAL
>>> ff20000000000000  80087000
>>>
>>> Copying data                                      : [100.0 %] |
>>> eta: 0s
>>>
>>> The dumpfile is saved to /mnt/dump.file1.
>>>
>>> makedumpfile Completed.
>>>
>>> # sudo ../crash/crash /home/song/9_linux/linux/00_rv_def/vmlinux 
>>> /tmp/hello/dump.file1
>>> ...
>>>         KERNEL: /home/song/9_linux/linux/00_rv_def/vmlinux
>>>       DUMPFILE: /tmp/hello/dump.file1  [PARTIAL DUMP]
>>>           CPUS: 2
>>>           DATE: Wed Sep 27 18:37:45 CST 2023
>>>         UPTIME: 00:00:18
>>> LOAD AVERAGE: 0.00, 0.00, 0.00
>>>          TASKS: 55
>>>       NODENAME: (none)
>>>        RELEASE: 6.6.0-rc1-00007-g22bfc766389c
>>>        VERSION: #1 SMP Mon Sep 25 19:29:05 CST 2023
>>>        MACHINE: riscv64  (unknown Mhz)
>>>         MEMORY: 511.8 MB
>>>          PANIC: "Kernel panic - not syncing: sysrq triggered crash"
>>>            PID: 1
>>>        COMMAND: "sh"
>>>           TASK: ff600000000e0000  [THREAD_INFO: ff600000000e0000]
>>>            CPU: 1
>>>          STATE: TASK_RUNNING (PANIC)
>>>
>>> crash> vtop 0xff20000000000000
>>> VIRTUAL           PHYSICAL
>>> ff20000000000000  80087000
>>>
>>>     PGD: ffffffff814fa900 => 20010c01
>>>     P4D: 0000000080043000 => 0000000020025401
>>>     PUD: 0000000080095000 => 0000000020025801
>>>     PMD: 0000000080096000 => 0000000020026001
>>>     PTE: 80098000 => 20021ce7
>>>    PAGE: 0000000080087000
>>>
>>>     PTE     PHYSICAL  FLAGS
>>> 20021ce7  80087000  (PRESENT|READ|WRITE|GLOBAL|ACCESSED|DIRTY)
>>>
>>>         PAGE       PHYSICAL      MAPPING       INDEX CNT FLAGS
>>> ff1c0000020021c0 80087000                0        0  1 0  // same as 
>>> the makedumpfile's vtop
>>>
>>>
>>> Song Shuai (2):
>>>     Add riscv64 support
>>>     riscv64: Correct the pfn_start for flatmem
>>>
>>>    Makefile       |   2 +-
>>>    arch/riscv64.c | 219 
>>> +++++++++++++++++++++++++++++++++++++++++++++++++
>>>    makedumpfile.c |  18 ++++
>>>    makedumpfile.h | 107 ++++++++++++++++++++++++
>>>    4 files changed, 345 insertions(+), 1 deletion(-)
>>>    create mode 100644 arch/riscv64.c
>