Kgdb uses brki r16, 0x18 instruction to call
low level _debug_exception function which save
current state to pt_regs and call microblaze_kgdb_break
function. _debug_exception should be called only from
the kernel space. User space calling is not supported
because user application debugging uses different handling.
pt_regs_to_gdb_regs loads additional special registers
which can't be changed
* Enable KGDB in Kconfig
* Remove ancient not-tested KGDB support
* Remove ancient _debug_exception code from entry.S
Only MMU KGDB support is supported.
Signed-off-by: Michal Simek <monstr@monstr.eu>
CC: Jason Wessel <jason.wessel@windriver.com>
CC: John Williams <john.williams@petalogix.com>
CC: Edgar E. Iglesias <edgar.iglesias@petalogix.com>
CC: linux-kernel@vger.kernel.org
Acked-by: Jason Wessel <jason.wessel@windriver.com>
This is the first patch which add support for
user application debugging through brki rX, 0x18 vector.
This patch has side effect which also remove security issue
to use brki rX, 0x18 to freeze kernel.
Support for old gdb support via priviledged exception
(brk r0, r0) is still there. It will be remove in future.
Signed-off-by: Michal Simek <monstr@monstr.eu>
Syscall can be called only from userspace that's why
we don't need to check which space kernel come from.
Kernel syscall calling is not check and shouldn't come
throught this part of code.
Signed-off-by: Michal Simek <monstr@monstr.eu>
We are not working with values from MSR that's why
we can discard it and use r11 for different purpose without
saving/restoring.
Signed-off-by: Michal Simek <monstr@monstr.eu>
Remove set_vms because UMS is cleared and VMS is already setup.
Optimize function calling which save one additional instruction.
Signed-off-by: Michal Simek <monstr@monstr.eu>
VMS is always setup because VM mode was before
exception/syscall/interrupt. Kernel continues in kernel mode
that's why we have to clear UMS bit if kernel comes from
user space.
Signed-off-by: Michal Simek <monstr@monstr.eu>
PT_MODE stores information if kernel comes from user
or kernel space. If come from user space, PT_MODE
contains 0. If come from kernel store, PT_MODE contains
non zero value. We don't need to save value 1. I am using
r1 register which contains non zero value.
This change save one additional instruction.
Signed-off-by: Michal Simek <monstr@monstr.eu>
Keep together all arguments for send_sig function.
Move returning address to delay slot which is executed.
Remove additional send_sig loading. I am using IMM part of
rtbd instruction with r0.
old solution:
addik r11, r0, send_sig
rtbd r11, 0
nop
new solution:
rtbd r0, send_sig
nop
There is one instruction saving.
Signed-off-by: Michal Simek <monstr@monstr.eu>
It is necessary to setup BIP and EE and clear EIP
only for unaligned exception handler. The rest of
hw exception handlers don't require it.
HW exception occured and we are not in virtual mode.
That's why we can do operations protected by EIP.
Interrupt, next hw exception or syscall can't occur.
EIP is cleared by rted.
This change speedup page_fault hw exception handler
which is critical path.
There is also necessary to save R11 content before
flag setup for unaligned exception.
Signed-off-by: Michal Simek <monstr@monstr.eu>
SAVE_STATE macro is used in hw exceptions high level handling
functions. Hw exception doesn't disable IRQ that's why we don't
need to reenable it.
Signed-off-by: Michal Simek <monstr@monstr.eu>
We don't need to protect by BIP whole ret_from_trap/ret_from_exc code.
Only restoring from user/hw exception should be covered.
If BIP is setup, IRQ can't occur.
Signed-off-by: Michal Simek <monstr@monstr.eu>
There is a way howto remove Kernel Mode variable. It is easier
to parse UMS bit in MSR to find out if I come from kernel or user
space. Loading MSR content should be in one cycle and loading
PER_CPU variable depends on memory state.
Signed-off-by: Michal Simek <monstr@monstr.eu>
Save and restore R3/R4 registers in macros. This change
help to cleanup entry.S.
In ret_from_trap function we are saving returning value from
syscall to pt_regs on stack that's why we don't need to save and
restore these values before kernel functions (schedule, do_signal).
Signed-off-by: Michal Simek <monstr@monstr.eu>
_start symbol stores physical address where kernel is.
Gdb uses this symbol for their purpose that's why
we have to rename it.
Signed-off-by: Michal Simek <monstr@monstr.eu>
Lower shifting values ensure that shifted 32bit counter
value doesn't exceed 64bit cycle variable too fast.
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>
Allow developer to configure memory page size at compile time.
Larger pages can improve performance on some workloads.
Based on PowerPC code.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
sys_clone syscall ignored args which this patch mapped to args
which are passing from glibc.
Here is the origin problem description.
"I ran the static libgcc tests (very few of them are there, they are
mostly dynamically linked) and some of them fail with an assertion in
fork() system call (tid != pid), I looked at the microblaze/entry.S
file and it looks suspicious (ignores arguments 3-5)"
Arg mapping should be:
glibc ARCH_FORK(...) -> do_fork(...)
r5 -> r5 (clone_flags)
r6 -> r6 (stack_start, use parent->stack if NULL)
pt_regs -> r7 (pt_regs)
r7 -> r8 (stack_size)
r8 -> r9 (parent_tidptr)
r9 -> r10 (child_tidptr)
Signed-off-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
copy_to_user_page macro is used in mm/memory.c:access_process_vm
function. This function is called from ptrace code (POKETEXT, POKEDATA)
which write data to memory. Microblaze handle physical address for
caches that's why there is virt_to_phys conversion.
There is potential one location which can caused the problem on WB system.
The important is take a look at write PTRACEs requests
(POKE/TEXT, DATA, USR).
Note:
Majority of Microblaze PTRACE code is moved to generic location
in newer kernel version that's why this solution should work on
the newest kernel version too.
linux/io.h is in cacheflush because of mm/nommu.c
Tested on a WB system - hello world debugging.
Signed-off-by: Michal Simek <monstr@monstr.eu>
via following scripts
FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
sed -i \
-e 's/lmb/memblock/g' \
-e 's/LMB/MEMBLOCK/g' \
$FILES
for N in $(find . -name lmb.[ch]); do
M=$(echo $N | sed 's/lmb/memblock/g')
mv $N $M
done
and remove some wrong change like lmbench and dlmb etc.
also move memblock.c from lib/ to mm/
Suggested-by: Ingo Molnar <mingo@elte.hu>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The commit "asm-generic: add NEED_SG_DMA_LENGTH to define sg_dma_len()"
18e98307de broke microblaze compilation.
dma_direct_map_sg() sets sg->dma_length, however microblaze doesn't
set NEED_SG_DMA_LENGTH so scatterlist strcutres doesn't include
dma_length.
sg->dma_length is always equal to sg->length on microblaze. So we
don't need to set set dma_length, that is, microblaze can simply use
sg->length.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Michal Simek <monstr@monstr.eu>
Merging in current state of Linus' tree to deal with merge conflicts and
build failures in vio.c after merge.
Conflicts:
drivers/i2c/busses/i2c-cpm.c
drivers/i2c/busses/i2c-mpc.c
drivers/net/gianfar.c
Also fixed up one line in arch/powerpc/kernel/vio.c to use the
correct node pointer.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
By moving dma_mask into pdev_archdata, and adding archdata to
struct of_device, it makes it possible to substitute of_device
with struct platform_device, which is a stepping stone to
removing the of_platform bus entirely.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch eliminates the node pointer from struct of_device and the
of_node (or prom_node) pointer from struct dev_archdata since the node
pointer is now part of struct device proper when CONFIG_OF is set, and
all users of the old pointer locations have already been converted over
to use device->of_node.
Also remove dev_archdata_{get,set}_node() as it is no longer used by
anything.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The following structure elements duplicate the information in
'struct device.of_node' and so are being eliminated. This patch
makes all readers of these elements use device.of_node instead.
(struct of_device *)->node
(struct dev_archdata *)->prom_node (sparc)
(struct dev_archdata *)->of_node (powerpc & microblaze)
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
CC arch/microblaze/kernel/cpu/cache.o
arch/microblaze/kernel/cpu/cache.c: In function '__invalidate_dcache_range_wb':
arch/microblaze/kernel/cpu/cache.c:398: warning: ISO C90 forbids mixed declarations and code
arch/microblaze/kernel/cpu/cache.c: In function '__flush_dcache_range_wb':
arch/microblaze/kernel/cpu/cache.c:509: warning: ISO C90 forbids mixed declara
Signed-off-by: Michal Simek <monstr@monstr.eu>
Modules that use copy_{to,from}_user(), memcpy(), and memset() fail to build
in certain circumstances.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
