linux_old1/arch/powerpc/xmon
Paul Gortmaker 21f585073d powerpc: Fix smp_processor_id() in preemptible splat in set_breakpoint
Currently, on 8641D, which doesn't set CONFIG_HAVE_HW_BREAKPOINT
we get the following splat:

BUG: using smp_processor_id() in preemptible [00000000] code: login/1382
caller is set_breakpoint+0x1c/0xa0
CPU: 0 PID: 1382 Comm: login Not tainted 3.15.0-rc3-00041-g2aafe1a4d451 #1
Call Trace:
[decd5d80] [c0008dc4] show_stack+0x50/0x158 (unreliable)
[decd5dc0] [c03c6fa0] dump_stack+0x7c/0xdc
[decd5de0] [c01f8818] check_preemption_disabled+0xf4/0x104
[decd5e00] [c00086b8] set_breakpoint+0x1c/0xa0
[decd5e10] [c00d4530] flush_old_exec+0x2bc/0x588
[decd5e40] [c011c468] load_elf_binary+0x2ac/0x1164
[decd5ec0] [c00d35f8] search_binary_handler+0xc4/0x1f8
[decd5ef0] [c00d4ee8] do_execve+0x3d8/0x4b8
[decd5f40] [c001185c] ret_from_syscall+0x0/0x38
 --- Exception: c01 at 0xfeee554
    LR = 0xfeee7d4

The call path in this case is:

	flush_thread
	   --> set_debug_reg_defaults
	     --> set_breakpoint
	       --> __get_cpu_var

Since preemption is enabled in the cleanup of flush thread, and
there is no need to disable it, introduce the distinction between
set_breakpoint and __set_breakpoint, leaving only the flush_thread
instance as the current user of set_breakpoint.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-05-20 10:54:06 +10:00
..
Makefile powerpc: Build kernel with -mcmodel=medium 2013-01-10 17:00:31 +11:00
ansidecl.h powerpc: Merge xmon 2005-10-28 22:53:37 +10:00
dis-asm.h [POWERPC] Make xmon disassembly optional 2006-12-04 20:40:32 +11:00
nonstdio.c powerpc/xmon: Fallback to printk() in xmon_printf() if udbg is not setup 2012-11-15 13:00:02 +11:00
nonstdio.h powerpc/xmon: Merge start.c into nonstdio.c 2012-11-15 12:59:46 +11:00
ppc-dis.c [POWERPC] Import updated version of ppc disassembly code for xmon 2006-12-04 20:40:36 +11:00
ppc-opc.c bug.h: add include of it to various implicit C users 2012-02-29 17:15:08 -05:00
ppc.h [POWERPC] Import updated version of ppc disassembly code for xmon 2006-12-04 20:40:36 +11:00
spu-dis.c [PATCH] arch/powerpc trivial annotations 2007-02-09 09:14:06 -08:00
spu-insns.h [POWERPC] Import spu disassembly code into xmon 2006-12-04 20:40:29 +11:00
spu-opc.c bug.h: add include of it to various implicit C users 2012-02-29 17:15:08 -05:00
spu.h [POWERPC] Import spu disassembly code into xmon 2006-12-04 20:40:29 +11:00
xmon.c powerpc: Fix smp_processor_id() in preemptible splat in set_breakpoint 2014-05-20 10:54:06 +10:00