linux-toradex.git/arch/parisc/kernel/unwind.c, branch v4.10

Replace with globally

2016-12-24T19:46:01+00:00

This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*'
  sed -i -e "s!$PATT!#include !" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro 
Signed-off-by: Linus Torvalds

parisc: Fix backtrace on PA-RISC

2016-06-04T20:05:07+00:00

This patch fixes backtrace on PA-RISC

There were several problems:

1) The code that decodes instructions handles instructions that subtract
from the stack pointer incorrectly. If the instruction subtracts the
number X from the stack pointer the code increases the frame size by
(0x100000000-X).  This results in invalid accesses to memory and
recursive page faults.

2) Because gcc reorders blocks, handling instructions that subtract from
the frame pointer is incorrect. For example, this function
	int f(int a)
	{
		if (__builtin_expect(a, 1))
			return a;
		g();
		return a;
	}
is compiled in such a way, that the code that decreases the stack
pointer for the first "return a" is placed before the code for "g" call.
If we recognize this decrement, we mistakenly believe that the frame
size for the "g" call is zero.

To fix problems 1) and 2), the patch doesn't recognize instructions that
decrease the stack pointer at all. To further safeguard the unwind code
against nonsense values, we don't allow frame size larger than
Total_frame_size.

3) The backtrace is not locked. If stack dump races with module unload,
invalid table can be accessed.

This patch adds a spinlock when processing module tables.

Note, that for correct backtrace, you need recent binutils.
Binutils 2.18 from Debian 5 produce garbage unwind tables.
Binutils 2.21 work better (it sometimes forgets function frames, but at
least it doesn't generate garbage).

Signed-off-by: Mikulas Patocka 
Signed-off-by: Helge Deller

parisc: use kernel_text_address() in unwind functions

2013-11-30T21:08:54+00:00

Signed-off-by: Helge Deller

parisc: unwind - optimise linked-list searches for modules

2010-10-22T01:12:19+00:00

Having many dozens of modules, the searches down the linked
list of sections would dominate the lookup time, dwarfing
any savings from the binary search within the section.

A simple move-to-front optimisation exploits the commonality
of the code paths taken, and in simple real-world tests
on other architectures reduced the number of steps in the
search to barely more than 1.

Signed-off-by: Phil Carmody 
Signed-off-by: Kyle McMartin

parisc: use sort() instead of home-made implementation (v2)

2009-12-16T03:48:55+00:00

Signed-off-by: Helge Deller 
Signed-off-by: Randolph Chung 
Signed-off-by: Kyle McMartin

parisc: add CALLER_ADDR{0-6} macros

2009-12-16T03:48:54+00:00

Signed-off-by: Helge Deller 
Signed-off-by: Kyle McMartin

parisc: fix unwind with recent gcc versions

2009-11-30T16:20:24+00:00

kernel unwinding is broken with gcc >= 4.x.  Part of the problem is that
binutils seems very sensitive to where the unwind information is stored.

Signed-off-by: Helge Deller 
Signed-off-by: Kyle McMartin 
Signed-off-by: Linus Torvalds

parisc: fix GFP_KERNEL use while atomic in unwinder

2009-01-05T18:15:25+00:00

Since unwind_frame_init_from_blocked_task() may be called from
interrupt/in_atomic context, it needs to kmalloc() memory with
GFP_ATOMIC instead of GFP_KERNEL.

This fixes this warning (ShowTasks called from sysrq handler):

BUG: sleeping function called from invalid context at mm/slab.c:3044
in_atomic(): 1, irqs_disabled(): 1, pid: 2119, name: miniruby
Backtrace:
 [<10132e78>] __might_sleep+0x4c/0x118
 [<1018f644>] kmem_cache_alloc+0x2c/0xb4
 [<1011bae0>] unwind_frame_init_from_blocked_task+0x30/0xa0
 [<1010fd3c>] parisc_show_stack+0x3c/0xac
 [<10132c7c>] show_state_filter+0x80/0xd8
 [<102f4074>] __handle_sysrq+0xd0/0x1b0
 [<102f9558>] receive_chars+0x22c/0x318
 [<102f9940>] serial8250_handle_port+0x40/0x88
 [<102f9a8c>] serial8250_interrupt+0x104/0x10c
 [<10161920>] handle_IRQ_event+0x44/0x94
 [<10161acc>] __do_IRQ+0x15c/0x1dc
 [<102c442c>] superio_interrupt+0x74/0xa8
 [<10161920>] handle_IRQ_event+0x44/0x94
 [<10161acc>] __do_IRQ+0x15c/0x1dc
 [<10110fb4>] do_cpu_irq_mask+0x90/0xbc
 [<10114068>] intr_return+0x0/0x4

Signed-off-by: Helge Deller 
Signed-off-by: Kyle McMartin

parisc: initialize unwinder much earlier

2008-10-10T16:32:30+00:00

The unwinder was being initialized way too late to be any use
debugging early boot crashes. Instead of relying on module_init
initcalls to initialize it, let's do it explicitly as early as
we can.

Signed-off-by: James Bottomley 
Signed-off-by: Kyle McMartin

[PARISC] Kill incorrect cast warning in unwinder

2007-10-18T07:59:04+00:00

Signed-off-by: Kyle McMartin