linux.git/arch/powerpc/kernel/misc_32.S, branch v2.6.28

powerpc/fsl-booke: Fix the miss interrupt restore

2008-12-17T16:06:13+00:00

The commit e5e774d8833de1a0037be2384efccadf16935675
powerpc/fsl-booke: Fix problem with _tlbil_va being interrupted
introduce one issue. that casue the problem like this:

Kernel BUG at c00b19fc [verbose debug info unavailable]
Oops: Exception in kernel mode, sig: 5 [#1]
MPC8572 DS
Modules linked in:
NIP: c00b19fc LR: c00b1c34 CTR: c0064e88
REGS: ef02b7b0 TRAP: 0700   Not tainted  (2.6.28-rc8-00057-g1bda712)
MSR: 00021000   CR: 44048028  XER: 20000000
TASK = ef02c000[1] 'init' THREAD: ef02a000
GPR00: 00000001 ef02b860 ef02c000 eec201a0 c0dec2c0 00000000 000078a1 00000400
GPR08: c00b4e40 000078a1 c048ec00 a1780000 44048028 ecd26917 00000001 ef02b948
GPR16: ffffffea 0000020c 00000000 00000000 00000003 0000000a 00000000 000078a1
GPR24: eec201a0 00000000 ed849000 00000400 ef02b95c 00000001 ef02b978 ef02b984
NIP [c00b19fc] __find_get_block+0x24/0x238
LR [c00b1c34] __getblk+0x24/0x2a0
Call Trace:
[ef02b860] [c017b768] generic_make_request+0x290/0x328 (unreliable)
[ef02b8b0] [c00b1c34] __getblk+0x24/0x2a0
[ef02b910] [c00b4ae4] __bread+0x14/0xf8
[ef02b920] [c00fc228] ext2_get_branch+0xf0/0x138
[ef02b940] [c00fcc88] ext2_get_block+0xb8/0x828
[ef02ba00] [c00bbdc8] do_mpage_readpage+0x188/0x808
[ef02bac0] [c00bc5b4] mpage_readpages+0xec/0x144
[ef02bb50] [c00fba38] ext2_readpages+0x24/0x34
[ef02bb60] [c006ade0] __do_page_cache_readahead+0x150/0x230
[ef02bbb0] [c0064bdc] filemap_fault+0x31c/0x3e0
[ef02bbf0] [c00728b8] __do_fault+0x60/0x5b0
[ef02bc50] [c0011e0c] do_page_fault+0x2d8/0x4c4
[ef02bd10] [c000ed90] handle_page_fault+0xc/0x80
[ef02bdd0] [c00c7adc] set_brk+0x74/0x9c
[ef02bdf0] [c00c9274] load_elf_binary+0x70c/0x1180
[ef02be70] [c00945f0] search_binary_handler+0xa8/0x274
[ef02bea0] [c0095818] do_execve+0x19c/0x1d4
[ef02bed0] [c000766c] sys_execve+0x58/0x84
[ef02bef0] [c000e950] ret_from_syscall+0x0/0x3c
[ef02bfb0] [c009c6fc] sys_dup+0x24/0x6c
[ef02bfc0] [c0001e04] init_post+0xb0/0xf0
[ef02bfd0] [c046c1ac] kernel_init+0xcc/0xf4
[ef02bff0] [c000e6d0] kernel_thread+0x4c/0x68
Instruction dump:
4bffffa4 813f000c 4bffffac 9421ffb0 7c0802a6 7d800026 90010054 bf210034
91810030 7c0000a6 68008000 54008ffe <0f000000> 3d20c04e 3b29ffb8 38000008

The issue was the beqlr returns early but we haven't reenabled interrupts.

Signed-off-by: Dave Liu 
Signed-off-by: Kumar Gala

powerpc/fsl-booke: Fix problem with _tlbil_va being interrupted

2008-12-13T23:02:47+00:00

An example calling sequence which we did see:

copy_user_highpage -> kmap_atomic -> flush_tlb_page -> _tlbil_va

We got interrupted after setting up the MAS registers before the
tlbwe and the interrupt handler that caused the interrupt also did
a kmap_atomic (ide code) and thus on returning from the interrupt
the MAS registers no longer contained the proper values.

Since we dont save/restore MAS registers for normal interrupts we
need to disable interrupts in _tlbil_va to ensure atomicity.

Signed-off-by: Kumar Gala

powerpc/fsl-booke: Fix synchronization bug w/local tlb invalidates

2008-11-08T18:38:55+00:00

The implemetation of _tlbil_pid() on Freescale Book-E cores needs
an msync & isync after we flash invalidate the TLBs.  This was causing
the following oops reported by Sebastian Andrzej Siewior:

  VFS: Mounted root (nfs filesystem) readonly.
  Freeing unused kernel memory: 148k init
  BUG: sleeping function called from invalid context at /home/bigeasy/git/linux-2.6-powerpc/mm/mmap.c:234
  in_atomic():1, irqs_disabled():0
  Call Trace:
  [df189df0] [c0007160] show_stack+0x48/0x148 (unreliable)
  [df189e30] [c0029480] __might_sleep+0xf0/0x100
  [df189e40] [c0070ac0] remove_vma+0x28/0x98
  [df189e50] [c0070c1c] exit_mmap+0xec/0x128
  [df189e80] [c002d2f4] mmput+0x54/0xec
  [df189ea0] [c0030b6c] exit_mm+0x10c/0x120
  [df189ed0] [c003288c] do_exit+0x1ac/0x6e8
  [df189f20] [c0032e48] do_group_exit+0x80/0xac
  [df189f40] [c000e9dc] ret_from_syscall+0x0/0x3c
  BUG: scheduling while atomic: udevd/956/0x10000002
  Modules linked in:
  Call Trace:
  [df189df0] [c0007160] show_stack+0x48/0x148 (unreliable)
  [df189e30] [c002ac88] __schedule_bug+0x58/0x6c
  [df189e40] [c023e6cc] schedule+0xa8/0x4a8
  [df189e90] [c002ad6c] __cond_resched+0x38/0x64
  [df189ea0] [c023ebc8] _cond_resched+0x3c/0x58
  [df189eb0] [c0030e70] put_files_struct+0x90/0xec
  [df189ed0] [c00328a8] do_exit+0x1c8/0x6e8
  [df189f20] [c0032e48] do_group_exit+0x80/0xac
  [df189f40] [c000e9dc] ret_from_syscall+0x0/0x3c

Signed-off-by: Kumar Gala

powerpc: Fix error path in kernel_thread function

2008-10-10T04:55:18+00:00

The powerpc 32-bit and 64-bit kernel_thread functions don't properly
propagate errors being returned by the clone syscall.  (In the case of
error, the syscall exit code returns a positive errno in r3 and sets
the CR0[SO] bit.)

This patch fixes that by negating r3 if CR0[SO] is set after the syscall.

Signed-off-by: Josh Poimboeuf 
Signed-off-by: Josh Boyer 
Acked-by: Paul Mackerras 
Signed-off-by: Benjamin Herrenschmidt

powerpc: Introduce local (non-broadcast) forms of tlb invalidates

2008-09-24T21:29:40+00:00

Introduced a new set of low level tlb invalidate functions that do not
broadcast invalidates on the bus:

_tlbil_all - invalidate all
_tlbil_pid - invalidate based on process id (or mm context)
_tlbil_va  - invalidate based on virtual address (ea + pid)

On non-SMP configs _tlbil_all should be functionally equivalent to _tlbia and
_tlbil_va should be functionally equivalent to _tlbie.

The intent of this change is to handle SMP based invalidates via IPIs instead
of broadcasts as the mechanism scales better for larger number of cores.

On e500 (fsl-booke mmu) based cores move to using MMUCSR for invalidate alls
and tlbsx/tlbwe for invalidate virtual address.

Signed-off-by: Kumar Gala

powerpc/kexec: Fix up KEXEC_CONTROL_CODE_SIZE missed during conversion

2008-08-18T04:22:35+00:00

Commit 163f6876f5c3ff8215e900b93779e960a56b3694 missed one, resulting in
the following compile error:

  AS      arch/powerpc/kernel/misc_32.o
arch/powerpc/kernel/misc_32.S: Assembler messages:
arch/powerpc/kernel/misc_32.S:902: Error: unsupported relocation against KEXEC_CONTROL_CODE_SIZE
make[2]: *** [arch/powerpc/kernel/misc_32.o] Error 1
make[1]: *** [arch/powerpc/kernel] Error 2
make: *** [vmlinux] Error 2

I grepped arch/ and found no further instances.

Signed-off-by: Paul Collins 
Signed-off-by: Paul Mackerras

powerpc/kprobes: Some minor fixes

2008-06-26T08:35:33+00:00

* Mark __flush_icache_range as a function that can't be probed since its
  used by the kprobe code.

* Fix an issue with single stepping and async exceptions.  We need to
  ensure that we dont get an async exception (external, decrementer, etc)
  while we are attempting to single step the probe point.

  Added a check to ensure we only handle a single step if its really
  intended for the instruction in question.

Signed-off-by: Kumar Gala

[POWERPC] Add IRQSTACKS support on ppc32

2008-04-29T05:57:34+00:00

This makes it possible to use separate stacks for hard and soft IRQs
on 32-bit powerpc as well as on 64-bit.  The code for 32-bit is just
the 32-bit analog of the 64-bit code.

* Added allocation and initialization of the irq stacks.  We limit the
  stacks to be in lowmem for ppc32.
* Implemented ppc32 versions of call_do_softirq() and call_handle_irq()
  to switch the stack pointers
* Reworked how we do stack overflow detection.  We now keep around the
  limit of the stack in the thread_struct and compare against the limit
  to see if we've overflowed.  We can now use this on ppc64 if desired.

[ paulus@samba.org: Fixed bug on 6xx where we need to reload r9 with the
  thread_info pointer. ]

Signed-off-by: Kumar Gala 
Signed-off-by: Paul Mackerras

[POWERPC] Clean up access to thread_info in assembly

2008-04-24T10:58:02+00:00

Use (31-THREAD_SHIFT) to get to thread_info from stack pointer.  This makes
the code a bit easier to read and more robust if we ever change THREAD_SHIFT.

Signed-off-by: Kumar Gala 
Signed-off-by: Paul Mackerras

[POWERPC] Add __ucmpdi2 for 64-bit comparisons in 32-bit kernels

2008-03-12T22:39:55+00:00

Some drivers (such as V4L2) have code that causes gcc to generate
calls to __ucmpdi2 when compiling for 32-bit powerpc, which results
in either a link-time error or a module that can't be loaded, as
we don't currently have a __ucmpdi2.  This adds one so these drivers
can be used.

Signed-off-by: Paul Mackerras