linux-toradex.git/arch/parisc/kernel/entry.S, branch v3.4.18

PARISC: fix TLB fault path on PA2.0 narrow systems

2012-06-09T15:36:07+00:00

commit 2f649c1f6f0fef445ce79a19b79e5ce8fe9d7f19 upstream.

commit 5e185581d7c46ddd33cd9c01106d1fc86efb9376
Author: James Bottomley 

    [PARISC] fix PA1.1 oops on boot

Didn't quite fix the crash on boot.  It moved it from PA1.1 processors to
PA2.0 narrow kernels.  The final fix is to make sure the [id]tlb_miss_20 paths
also work.  Even on narrow systems, these paths require using the wide
instructions becuase the tlb insertion format is wide.  Fix this by
conditioning the dep[wd],z on whether we're being called from _11 or _20[w]
paths.

Tested-by: Helge Deller 
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman

[PARISC] fix PA1.1 oops on boot

2012-05-16T10:14:45+00:00

All PA1.1 systems have been oopsing on boot since

commit f311847c2fcebd81912e2f0caf8a461dec28db41
Author: James Bottomley 
Date:   Wed Dec 22 10:22:11 2010 -0600

    parisc: flush pages through tmpalias space

because a PA2.0 instruction was accidentally introduced into the PA1.1 TLB
insertion interruption path when it was consolidated with the do_alias macro.
Fix the do_alias macro only to use PA2.0 instructions if compiled for 64 bit.
Cc: stable@vger.kernel.org  #2.6.39+
Signed-off-by: James Bottomley

[PARISC] only make executable areas executable

2011-04-15T17:55:18+00:00

Currently parisc has the whole kernel marked as RWX, meaning any
kernel page at all is eligible to be executed.  This can cause a
theoretical problem on systems with combined I/D TLB because the act
of referencing a page causes a TLB insertion with an executable bit.
This TLB entry may be used by the CPU as the basis for speculating the
page into the I-Cache.  If this speculated page is subsequently used
for a user process, there is the possibility we will get a stale
I-cache line picked up as the binary executes.

As a point of good practise, only mark actual kernel text pages as
executable.  The same has to be done for init_text pages, but they're
converted to data pages (and the I-Cache flushed) when the init memory
is released.

Signed-off-by: James Bottomley

Fix common misspellings

2011-03-31T14:26:23+00:00

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi

eliminate special FLUSH flag from page table

2011-01-15T14:45:54+00:00

This was used to flush a region even if the page table entry had been
cleared.  In theory this was never necessary, but now we've switched to
alias based flushing, the whole set of code associated with it can be dumped.

Signed-off-by: James Bottomley 
Signed-off-by: James Bottomley

parisc: flush pages through tmpalias space

2011-01-15T14:44:40+00:00

The kernel has an 8M tmpailas space (originally designed for copying
and clearing pages but now only used for clearing).  The idea is
to place zeros into the cache above a physical page rather than into
the physical page and flush the cache, because often the zeros end up
being replaced quickly anyway.

We can also use the tmpalias space for flushing a page.  The difference
here is that we have to do tmpalias processing in the non access data and
instruction traps.  The principle is the same: as long as we know the physical
address and have a virtual address congruent to the real one, the flush will
be effective.

In order to use the tmpalias space, the icache miss path has to be enhanced to
check for the alias region to make the fic instruction effective.

Signed-off-by: James Bottomley

parisc: Remove unnecessary macros from entry.S

2010-05-30T09:47:28+00:00

The EXTR, DEP and DEPI macros are unnecessary.  There are PA 1.X
pneumonics available with the same functionality, and the DEP and DEPI
macros conflict with assembler pneumonics.

Tested on a variety of 32 and 64-bit systems.

Signed-off-by: John David Anglin 
Signed-off-by: Kyle McMartin

parisc: Delete unnecessary nop's in entry.S

2010-05-30T09:45:22+00:00

Signed-off-by: John David Anglin 
Signed-off-by: Kyle McMartin

parisc: Avoid interruption in critical region in entry.S

2010-05-30T09:44:36+00:00

Signed-off-by: John David Anglin 
Signed-off-by: Kyle McMartin

parisc: stop using task->ptrace for {single,block}step flags

2009-09-28T03:07:22+00:00

task->ptrace flags belong to generic code, so instead thief some
TIF_ bits to use. Somewhat risky conversion of code to test TASK_FLAGS
instead of TASK_PTRACE in assembly, but it looks alright in the end.

Signed-off-by: Kyle McMartin