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>
Microblaze has support for early printk. The second serial
driver (uart16550/8250) has no microblaze support for early
printk.
Signed-off-by: Michal Simek <monstr@monstr.eu>
HAVE_ARCH_PCI_SET_DMA_MASK was removed in 2.6.34 (no architecture has
the own implementation of pci_set_dma_mask).
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
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>
The label should be remove by
21e1c93631
Warning message:
arch/microblaze/mm/fault.c: In function 'do_page_fault':
arch/microblaze/mm/fault.c:229: warning: label 'survive' defined but not used
Signed-off-by: Michal Simek <monstr@monstr.eu>
__copy_to/from_user_inatomic should call __copy_to/from_user
because there is not necessary to check access because of kernel function.
might_sleep in copy_to/from_user macros is causing problems
in debug sessions too (CONFIG_DEBUG_SPINLOCK_SLEEP).
BUG: sleeping function called from invalid context at
.../arch/microblaze/include/asm/uaccess.h:388
in_atomic(): 1, irqs_disabled(): 0, pid: 1, name: swapper
1 lock held by swapper/1:
#0: (&p->cred_guard_mutex){......}, at: [<c00d4b90>] prepare_bprm_creds+0x2c/0x88
Kernel Stack:
...
Call Trace:
[<c0006bd4>] microblaze_unwind+0x7c/0x94
[<c0006684>] show_stack+0xf4/0x190
[<c0006730>] dump_stack+0x10/0x30
[<c00103a0>] __might_sleep+0x12c/0x160
[<c0090de4>] file_read_actor+0x1d8/0x2a8
[<c0091568>] generic_file_aio_read+0x6b4/0xa64
[<c00cd778>] do_sync_read+0xac/0x110
[<c00ce254>] vfs_read+0xc8/0x160
[<c00d585c>] kernel_read+0x38/0x64
[<c00d5984>] prepare_binprm+0xfc/0x130
[<c00d6430>] do_execve+0x228/0x370
[<c000614c>] microblaze_execve+0x58/0xa4
caused by file_read_actor (mm/filemap.c) which calls
__copy_to_user_inatomic.
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>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: clear bridge resource range if BIOS assigned bad one
PCI: hotplug/cpqphp, fix NULL dereference
Revert "PCI: create function symlinks in /sys/bus/pci/slots/N/"
PCI: change resource collision messages from KERN_ERR to KERN_INFO
Yannick found that video does not work with 2.6.34. The cause of this
bug was that the BIOS had assigned the wrong range to the PCI bridge
above the video device. Before 2.6.34 the kernel would have shrunk
the size of the bridge window, but since
d65245c PCI: don't shrink bridge resources
the kernel will avoid shrinking BIOS ranges.
So zero out the old range if we fail to claim it at boot time; this will
cause us to allocate a new range at startup, restoring the 2.6.34
behavior.
Fixes regression https://bugzilla.kernel.org/show_bug.cgi?id=16009.
Reported-by: Yannick <yannick.roehlly@free.fr>
Acked-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.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>
The commit "mm: Move ARCH_SLAB_MINALIGN and
ARCH_KMALLOC_MINALIGN to <linux/slab_def.h>"
1f0ce8b3dd which moved the ARCH_SLAB_MINALIGN
default into the global header broke FLAT for Microblaze.
Error message:
slab error in verify_redzone_free(): cache `idr_layer_cache':
memory outside object was overwritten
Signed-off-by: Michal Simek <monstr@monstr.eu>
