On 9/23/2016 3:17 PM, Peter Zijlstra wrote:
On Fri, Sep 23, 2016 at 02:57:39PM -0500, Babu Moger wrote:
We checked again. Yes, It goes in .bss section. But in sparc we have
to fit .text, .data, .bss in 7 permanent TLBs(that is totally 28MB).
It was fine so far. But the commit 1413c0389333 ("lockdep: Increase
static allocations") added extra 4MB which makes it go beyond 28MB.
That is causing system boot up problems in sparc.
*sigh*, why didn't you start with that :/
Yes. We know it. This is a limitation. Changing this limit in our
hardware is a much bigger change which we cannot address right away.
So, we are trying to come up with a solution which can work for all. I
will re-post the patches with CONFIG_BASE_SMALL option if there is no
objections.
OK, so double check BASE_SMALL doesn't imply other things you cannot
live with, Sparc64 isn't a dinky system. If BASE_SMALL works for you
then good, otherwise do a PROVE_LOCKING_SMALL symbol that is not user
selectable and have SPARC select that. Use the invisible Help for that
symbol to explain all this again.
Thanks. Will work on it.
CCing David Miller and Rob Gardner. They might be able to explain
more if you have any more questions.
Nah, I think I remember enough of how the Sparc MMU works to see reason.
