Unaligned code use shift for finding register operand.
There is used BSRLI(r8,r8,2) macro which is expand for BS=0, DIV=1
by
ori rD, r0, (1 << imm); \
idivu rD, rD, rA
but if rD is equal rA then ori instruction rewrite value which
should be devide.
The patch remove this macro which use idivu instruction because
idivu takes 32/34 cycles. The highest shifting is 20 which takes
20 cycles.
Signed-off-by: Michal Simek <monstr@monstr.eu>
Implement intelligent backtracing by searching for stack frame creation,
and emitting only return addresses. Use print_hex_dump() to display the
entire binary kernel stack.
Limitation: MMU kernels are not currently able to trace beyond a system trap
(interrupt, syscall, etc.). It is the intent of this patch to provide
infrastructure that can be extended to add this capability later.
Changes from V1:
* Removed checks in find_frame_creation() that prevented location of the frame
creation instruction in heavily optimized code
* Various formatting/commenting/file location tweaks per review comments
* Dropped Kconfig option to enable STACKTRACE as something logically separate
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Previous patch d63678d607d0e37ec7abe5ceb545d7e8aab956a4 clear
it for noMMU kernel. This one do it for MMU.
Correct noMMU version
Signed-off-by: Michal Simek <monstr@monstr.eu>
FSR is sticky, so after the userspace exception/signal generation, clear
it ready for next time.
Signed-off-by: John Williams <john.williams@petalogix.com>
I thought that this part of code could be removed because just
save and restore MSR but any code can't change it. But seems to
that any part of code works with this information.
This patch solved problem with allocation.
Signed-off-by: Michal Simek <monstr@monstr.eu>
This patch add support for cases where load/store instruction
in put/get_user macro gets unaligned pointer to data and this
address is not valid. I prevent all cases which can failed.
I had to disable first stage of unaligned handler which is used
only for noMMU kernel and the whole work is done when interrupt
is enabled.
You have enable HW support for detect unaligned access in Microblaze.
This patch fixed three LTP tests:
getpeername01, getsockname01, socketpair01
Signed-off-by: Michal Simek <monstr@monstr.eu>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: John Linn <john.linn@xilinx.com>
Acked-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
