linux/arch/powerpc
Benjamin Herrenschmidt 08f1ec8a59 powerpc: Fix page fault with lockdep regression
commit a546498f3b
introduced a regression on 32-bit when irq tracing
is enabled by exposing an old bug in our irq tracing
code for exception entry.

The code would save and restore some GPRs around the
calls to the C lockdep code, however, it tries to be
too smart for its own good and restores some of the
GPRs from the exception frame (as saved there on
exception entry).

However, for page faults, we do replace those GPRs with
arguments to do_page_fault before we call transfer_to_handler
and so restoring from the exception frame is plain wrong in
this case.

This was fine as long as we didn't touch the interrupt state
when taking page fault, but when I started doing it, it would
trigger the lockdep calls and the bug.

This fixes it by cleaning up that code a bit. It did create
a small stack frame for the sake of backtraces, so let's
make it a bit bigger and use it to save and restore the
stuff we care about.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-04-10 17:21:35 +10:00
..
boot powerpc/dts: Removed fsl,msi property from dts. 2012-03-29 08:14:15 -05:00
configs Merge remote-tracking branch 'kumar/next' into merge 2012-04-02 13:57:46 +10:00
include/asm Merge remote-tracking branch 'kumar/next' into merge 2012-04-02 13:57:46 +10:00
kernel powerpc: Fix page fault with lockdep regression 2012-04-10 17:21:35 +10:00
kvm powerpc/kvm: Fallout from system.h disintegration 2012-04-02 14:00:04 +10:00
lib Disintegrate asm/system.h for PowerPC 2012-03-28 18:30:02 +01:00
math-emu powerpc/math_emu/efp: Look for errata handler when type mismatches 2011-10-06 23:36:47 -05:00
mm Disintegrate and delete asm/system.h 2012-03-28 15:58:21 -07:00
net net: filter: BPF 'JIT' compiler for PPC64 2011-07-21 12:38:32 -07:00
oprofile Disintegrate asm/system.h for PowerPC 2012-03-28 18:30:02 +01:00
perf powerpc/perf: Fix instruction address sampling on 970 and Power4 2012-03-28 11:33:24 +11:00
platforms powerpc/eeh: Fix use of set_current_state() in eeh event handling set_current_state() wart 2012-04-02 14:31:19 +10:00
sysdev Merge remote-tracking branch 'kumar/next' into merge 2012-04-02 13:57:46 +10:00
xmon Disintegrate and delete asm/system.h 2012-03-28 15:58:21 -07:00
Kconfig Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-03-29 16:53:48 -07:00
Kconfig.debug irqdomain: Remove powerpc dependency from debugfs file 2012-03-29 14:31:02 -06:00
Makefile powerpc/perf: Move perf core & PMU code into a subdirectory 2012-02-23 10:50:04 +11:00
relocs_check.pl powerpc: Process dynamic relocations for kernel 2011-12-20 10:21:08 -05:00