diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/blackfin/kernel/fixed_code.S | 14 | ||||
| -rw-r--r-- | arch/blackfin/kernel/setup.c | 2 | ||||
| -rw-r--r-- | arch/blackfin/mach-common/entry.S | 2 |
3 files changed, 17 insertions, 1 deletions
diff --git a/arch/blackfin/kernel/fixed_code.S b/arch/blackfin/kernel/fixed_code.S index d8b1ebc70996..90262691b11a 100644 --- a/arch/blackfin/kernel/fixed_code.S +++ b/arch/blackfin/kernel/fixed_code.S @@ -129,4 +129,18 @@ ENTRY(_atomic_xor32) rts; ENDPROC (_atomic_ior32) +.align 16 + /* + * safe_user_instruction + * Four NOPS are enough to allow the pipeline to speculativily load + * execute anything it wants. After that, things have gone bad, and + * we are stuck - so panic. Since we might be in user space, we can't + * call panic, so just cause a unhandled exception, this should cause + * a dump of the trace buffer so we can tell were we are, and a reboot + */ +ENTRY(_safe_user_instruction) + NOP; NOP; NOP; NOP; + EXCPT 0x4; +ENDPROC(_safe_user_instruction) + ENTRY(_fixed_code_end) diff --git a/arch/blackfin/kernel/setup.c b/arch/blackfin/kernel/setup.c index fc22ec8c2f47..934234f43839 100644 --- a/arch/blackfin/kernel/setup.c +++ b/arch/blackfin/kernel/setup.c @@ -431,6 +431,8 @@ void __init setup_arch(char **cmdline_p) != ATOMIC_AND32 - FIXED_CODE_START); BUG_ON((char *)&atomic_xor32 - (char *)&fixed_code_start != ATOMIC_XOR32 - FIXED_CODE_START); + BUG_ON((char *)&safe_user_instruction - (char *)&fixed_code_start + != SAFE_USER_INSTRUCTION - FIXED_CODE_START); init_exception_vectors(); bf53x_cache_init(); diff --git a/arch/blackfin/mach-common/entry.S b/arch/blackfin/mach-common/entry.S index e3ad5802868a..1b13fa470977 100644 --- a/arch/blackfin/mach-common/entry.S +++ b/arch/blackfin/mach-common/entry.S @@ -917,7 +917,7 @@ ENTRY(_ex_table) .long _ex_soft_bp /* 0x01 - User Defined - Software breakpoint */ .long _ex_replaceable /* 0x02 - User Defined */ .long _ex_trap_c /* 0x03 - User Defined - userspace stack overflow */ - .long _ex_replaceable /* 0x04 - User Defined */ + .long _ex_trap_c /* 0x04 - User Defined - dump trace buffer */ .long _ex_replaceable /* 0x05 - User Defined */ .long _ex_replaceable /* 0x06 - User Defined */ .long _ex_replaceable /* 0x07 - User Defined */ |