Re: [Freeipmi-devel] [RFC][PATCH 0/1] Fix apparent bug w/ ACPI SPMI table parsing

[Albert Chu]

Hey Dann,

As I thought about it, I'm not sure how much the ACPI code has even
been tested (atleast by me).  Almost every motherboard I can recall had
info in DMI/SMBIOS.

Digging into the code history, outside of cleanups & refactoring (which
of course could have introduced issues, but I doubt those issues would
have been at the level of what you found), this code was developed
circa 2004-2005, with the last "real" change in 2006.

So I'm willing to accept your change as is b/c A) it makes sense, B)
you seem to have a system you can half-test against and C) I assume
this code worked long ago on whatever system it was originally
developed against, but who knows if that system even did it correctly.

That said, you seem to be suggesting there are going to be some further
patches down the line for acpi via sysfs.  If that code is coming down
the pipeline, and this code is for it, I can wait for the entire patch
series to come in and it can be added all at once.

Al

On Mon, 2018-07-30 at 15:30 -0600, dann frazier wrote:
> hey.
>   I'm working on a patch to add support to ipmi-locate code to parse
> ACPI
> SPMI tables via sysfs. This is to make ipmi-locate work on an ARM
> system
> we have that describes its BMC only in ACPI (not DMI). Being ARM,
> trolling
> /dev/mem isn't safe, (freeipmi ifdef's that out), so using the
> kernel-exposed
> tables, when available, is a better option.
> 
> While doing this I ran across what seems like a bug, which the
> following patch
> should fix. I say "seems" and "should" because I don't have a system
> where the
> existing /dev/mem snooping code works - with, or without this bug fix
> -
> therefore, I cannot emperically demonstrate the bug. On the systems
> I've
> tested, which do include an SPMI table, ipmi-locate is unable to find
> a valid
> RSDT signature using the /dev/mem method. I'm not sure what I'm doing
> wrong
> there - I tried diabling CONFIG_STRICT_DEVMEM andsetting the
> vm.mmap_min_addr
> sysctl to 0 w/o luck.
> 
> dann frazier (1):
>   Don't try to separate the header from the ACPI table data
> 
>  libfreeipmi/locate/ipmi-locate-acpi-spmi.c | 33 +++-----------------
> --
>  1 file changed, 4 insertions(+), 29 deletions(-)
> 
-- 
Albert Chu
address@hidden
Computer Scientist
High Performance Systems Division
Lawrence Livermore National Laboratory