kernel_optimize_test/arch/sh/include
Frederic Weisbecker b2812d031d hw-breakpoints: Change/Enforce some breakpoints policies
The current policies of breakpoints in x86 and SH are the following:

- task bound breakpoints can only break on userspace addresses
- cpu wide breakpoints can only break on kernel addresses

The former rule prevents ptrace breakpoints to be set to trigger on
kernel addresses, which is good. But as a side effect, we can't
breakpoint on kernel addresses for task bound breakpoints.

The latter rule simply makes no sense, there is no reason why we
can't set breakpoints on userspace while performing cpu bound
profiles.

We want the following new policies:

- task bound breakpoint can set userspace address breakpoints, with
no particular privilege required.
- task bound breakpoints can set kernelspace address breakpoints but
must be privileged to do that.
- cpu bound breakpoints can do what they want as they are privileged
already.

To implement these new policies, this patch checks if we are dealing
with a kernel address breakpoint, if so and if the exclude_kernel
parameter is set, we tell the user that the breakpoint is invalid,
which makes a good generic ptrace protection.
If we don't have exclude_kernel, ensure the user has the right
privileges as kernel breakpoints are quite sensitive (risk of
trap recursion attacks and global performance impacts).

[ Paul Mundt: keep addr space check for sh signal delivery and fix
  double function declaration]

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: K. Prasad <prasad@linux.vnet.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2010-05-01 04:32:10 +02:00
..
asm hw-breakpoints: Change/Enforce some breakpoints policies 2010-05-01 04:32:10 +02:00
cpu-common/cpu
cpu-sh2/cpu sh: Mass ctrl_in/outX to __raw_read/writeX conversion. 2010-01-26 12:58:40 +09:00
cpu-sh2a/cpu
cpu-sh3/cpu dmaengine: shdma: separate DMA headers. 2010-03-02 11:09:04 +09:00
cpu-sh4/cpu sh: update the TLB replacement counter for entry wiring. 2010-03-26 11:37:16 +09:00
cpu-sh5/cpu
mach-common/mach sh: Mass ctrl_in/outX to __raw_read/writeX conversion. 2010-01-26 12:58:40 +09:00
mach-dreamcast/mach sh: mach-dreamcast: Convert to sparseirq. 2010-02-02 18:01:55 +09:00
mach-ecovec24/mach sh: mach-ecovec24: Remove un-defined settings for VPU 2009-12-04 13:42:34 +09:00
mach-kfr2r09/mach sh: LCDC start_transfer() for the KFR2R09 board 2009-12-09 12:40:45 +09:00
mach-landisk/mach
mach-migor/mach sh: audio support for the sh7722 Migo-R board 2010-03-02 11:08:54 +09:00
mach-sdk7786/mach sh: mach-sdk7786: Probe system FPGA area mapping. 2010-01-20 18:25:19 +09:00
mach-se/mach sh: mach-se: Convert SE7343 FPGA to dynamic IRQ allocation. 2010-01-12 13:37:04 +09:00
mach-sh03/mach