[Crash-utility] [PATCH v3 0/6] Second phase of future support for x86_64 5-level page tables

[Dave Anderson]

Hello Dou,

I have reviewed this second phase patchset, and have successfully tested it on
existing kernels.  I must say that it is *very* well done -- I truly appreciate
the effort that you have undertaken.

The only thing I added was a reference to the "--machdep vm=5level"
command line option in the crash.8 man page and for "crash --help".

I've queued it for crash-7.2.1:
  
  https://github.com/crash-utility/crash/commit/94d01ce01d7bdd7e3bbc5dccb25caac438c071b6

I look forward to phase 3!

Thanks,
  Dave

----- Original Message -----
> Changelog:
>   V1-->V2:
>     -Fix the backwards compatibility issues suggested by Dave
>     -Test with "mod","kmem -f","vm -p" command again.
>   V2-->V3:
>     -keep the pml4, upml, last_upml_read and last_pml4_read members in struct
>      machine_specific like before for extension modules suggested by Dave
>     -move ptrs_per_pgd to the end of the machine_specific data structure
>     -rewirte the changelog
>     -rebase the patchset
>     -retest it
> 
> I found Dave had alread done the first phase of future support for x86_64
> 5-level page tables(commit 307e7f35f510). when I asked him about the
> state of this work, he gave me a more detailed answer and suggestion.
> I follow his advice, and do the following job.
> 
> 1. Refine the original logical:
>   1) Create some new common function for getting the offset of page table
>   2) Repace the PML4 and UPML with the common PGD:
>      machdep->machspec->pml4/upml ==> machdep->pdg
>   3) Using the PUD in x86_64
> 
> 2. Add 5-level page tables support for x86_64_k/uvtop()
> 
> This patchset is the second phase of the work, As Dave said, we need to be
> a manner of determining very early on whether the kernel page tables are
> using 5-level and  whether each user-space task is using 4- or 5-level page
> tables. These will be done after this phase.
> 
> About test work:
> 
> I have tested this patchset with 4-level and 5-level paging table.
> 
> sadump are not be tested.
> 
> Dou Liyang (6):
>   defs.h: Fix the PHYSICAL_PAGE_MASK macro
>   x86_64: Extract public page table mapping code
>   x86_64: Unify the page table parsing for 4-level mode
>   x86_64.c: Add the VMEMMAP support for 5 level page table
>   x86_64: Add 5-level paging support for x86_64_k/uvtop()
>   x86_64: Fix the misusage of PGDIR_SHIFT
> 
>  defs.h   |  56 ++---
>  sadump.c |   7 +-
>  x86_64.c | 750
>  +++++++++++++++++++++++++++++++++------------------------------
>  3 files changed, 418 insertions(+), 395 deletions(-)
> 
> --
> 2.14.3
> 
> 
> 
>