Re: [Crash-utility] [PATCH v3 0/3] vmalloc translation support for PPC
----- Original Message -----
The following series implements :
* An infrastructure for platform based vmalloc translation for PPC32
* vmalloc translation support for PPC44x
Changes since V2:
* Rebased to crash-6.0.3
* Maintains a list of probe functions, rather than platform
definitions.
Each platform can define their own probe_function which would get the name of the
ppc platform (read from kernel) and the probe can check if the platform is one of its
variant. The probe function can then update the 'platform' defintions for the
virtual
address translation.
If none of the defined platforms match, falls back to using the default PPC32
definitions.
---
Suzuki K. Poulose (3):
[ppc] virtual address translation bits for PPC44x
[ppc] Support for platform based Virtual address translation
[ppc] Non-linear address translation routine
Hi Suzuki,
I'll defer the technical ACK to Toshi, but I do have a couple of other suggestions.
Here's a sample vmalloc translation:
crash> vtop d1180000
VIRTUAL PHYSICAL
d1180000 ff800000
Using ppc440gp board definitions:
PAGE DIRECTORY: c056f000
PGD: c0570a20 => c784b000
PMD: c784b000 => c784bc00
PTE: c784bc00 => 1ff80051b
PAGE: ff800000
PTE PHYSICAL FLAGS
ff80051b ff800000 (PRESENT|USER|GUARDED|COHERENT|ACCESSED)
PAGE PHYSICAL MAPPING INDEX CNT FLAGS
crash>
This may have been a pre-existing issue, but for vmalloc addresses, the
page struct translation at the end of the display (under PAGE PHYSICAL MAPPING...)
is missing for vmalloc addresses. For user-space and unity-mapped
addresses the translation is done as intended:
User-space:
crash> vtop ff8f000
VIRTUAL PHYSICAL
ff8f000 6b90000
Using ppc440gp board definitions:
PAGE DIRECTORY: c7a3a000
PGD: c7a3a1fc => c7bfc000
PMD: c7bfc000 => c7bfcc78
PTE: c7bfcc78 => 6b9005b
PAGE: 6b90000
PTE PHYSICAL FLAGS
6b9005b 6b90000 (PRESENT|USER|GUARDED|COHERENT|WRITETHRU)
VMA START END FLAGS FILE
c7b09898 ff8f000 ff92000 100073
PAGE PHYSICAL MAPPING INDEX CNT FLAGS
c06b5200 6b90000 c7a9fc61 ff8f 1 80068
crash>
Kernel unity-mapped:
crash> vtop c7b14000
VIRTUAL PHYSICAL
c7b14000 7b14000
Using ppc440gp board definitions:
PAGE DIRECTORY: c056f000
PGD: c05708f4 => 0
PAGE PHYSICAL MAPPING INDEX CNT FLAGS
c06d4280 7b14000 0 0 1 0
crash>
That should be a trivial fix.
Secondly, that "Using ppc440gp board definitions:" statement
stuck in the midst of the "vtop" output is not the place for it,
except perhaps if it's enclosed with a CRASHDEBUG() qualifier.
That being said, it certainly is a useful piece of information,
and should be made available somewhere.
What I suggest is that you create a PPC "machine_specific" data
structure like the other architectures have, and which the global
machdep_table structure points to. Then have it either contain,
or at least point to, your new base_platform structure, and
enhance ppc_dump_machdep_table() to dump its contents for the
"help -m" output.
Furthermore, the board's name string seems worthy of display in
ppc_cmd_mach() for the "mach" command, don't you?
Thanks,
Dave