Re: acpi_evaluate_integer broken by design



Now I know why I had strange "scheduling in atomic" problems:
acpi_evaluate_integer() does malloc(..., irqs_disabled() ? GFP_ATOMIC
: GFP_KERNEL)... which is (of course) broken.

That is kinda weird. When did this all start happening?

There's no way to reliably tell if we need GFP_ATOMIC or not from
code, this one for example fails to detect spinlocks held.

Len, this looks like 2.6.28 material. But given the poor quality of
the changelog it is hard to be sure about this. Why isn't everyone
seeing these warnings? What did Pavel do to provoke these alleged
warnings? Nobody knows...

I don't know know why pavel sees this and nobody else --
maybe something unusual he's doing with suspend?

The reason that the ACPI code is littered with bogus
irqs_disabled() ? GFP_ATOMIC : GFP_KERNEL)
is because, like boot, resume starts life with interrupts off.

I would prefer that resume and boot handle this the same way,
with system_state. However, a few years ago when I suggested
using system_state for resume, Andrew thought that was a very
bad idea. Andrew, do you still feel that way?

-Len

ps. I'll put this particular fix in my tree now.
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