diff options
| -rw-r--r-- | asm/head.S | 22 | ||||
| -rw-r--r-- | core/cpu.c | 13 | ||||
| -rw-r--r-- | core/stack.c | 13 | ||||
| -rw-r--r-- | include/cpu.h | 1 | ||||
| -rw-r--r-- | include/mem-map.h | 10 | ||||
| -rw-r--r-- | include/stack.h | 9 |
6 files changed, 52 insertions, 16 deletions
@@ -30,12 +30,17 @@ #define PPC_INST_STOP .long 0x4c0002e4 -#define GET_STACK(stack_reg,pir_reg) \ - sldi stack_reg,pir_reg,STACK_SHIFT; \ - addis stack_reg,stack_reg,CPU_STACKS_OFFSET@ha; \ +#define GET_STACK(stack_reg,pir_reg) \ + sldi stack_reg,pir_reg,STACK_SHIFT; \ + addis stack_reg,stack_reg,CPU_STACKS_OFFSET@ha; \ addi stack_reg,stack_reg,CPU_STACKS_OFFSET@l; -#define GET_CPU() \ +#define GET_EMERGENCY_STACK(stack_reg,pir_reg) \ + sldi stack_reg,pir_reg,STACK_SHIFT; \ + addis stack_reg,stack_reg,EMERGENCY_CPU_STACKS_OFFSET@ha; \ + addi stack_reg,stack_reg,EMERGENCY_CPU_STACKS_OFFSET@l; + +#define GET_CPU() \ clrrdi %r13,%r1,STACK_SHIFT #define SAVE_GPR(reg,sp) std %r##reg,STACK_GPR##reg(sp) @@ -1013,8 +1018,17 @@ opal_entry: b 1b 4: /* Quiesce protocol done, get our per CPU stack */ + /* Emergency stack if we have re-entered OPAL */ + lwz %r11,CPUTHREAD_IN_OPAL_CALL(%r12) + cmpwi %r11,1 + mfspr %r12,SPR_PIR + beq 5f GET_STACK(%r12,%r12) + b 6f +5: + GET_EMERGENCY_STACK(%r12,%r12) +6: stdu %r12,-STACK_FRAMESIZE(%r12) /* Save caller r1, establish new r1 */ @@ -79,15 +79,18 @@ unsigned long __attrconst cpu_stack_bottom(unsigned int pir) unsigned long __attrconst cpu_stack_top(unsigned int pir) { - /* This is the top of the MC stack which is above the normal - * stack, which means a SP between cpu_stack_bottom() and - * cpu_stack_top() can either be a normal stack pointer or - * a Machine Check stack pointer - */ + /* This is the top of the normal stack. */ return ((unsigned long)&cpu_stacks[pir]) + NORMAL_STACK_SIZE - STACK_TOP_GAP; } +unsigned long __attrconst cpu_emergency_stack_top(unsigned int pir) +{ + /* This is the top of the emergency stack, above the normal stack. */ + return ((unsigned long)&cpu_stacks[pir]) + + NORMAL_STACK_SIZE + EMERGENCY_STACK_SIZE - STACK_TOP_GAP; +} + static void cpu_wake(struct cpu_thread *cpu) { /* Is it idle ? If not, no need to wake */ diff --git a/core/stack.c b/core/stack.c index 10118e4..73700ce 100644 --- a/core/stack.c +++ b/core/stack.c @@ -71,7 +71,7 @@ void ___print_backtrace(unsigned int pir, struct bt_entry *entries, static char bt_text_buf[4096]; int i, l = 0, max; char *buf = out_buf; - unsigned long bottom, top, tbot, ttop; + unsigned long bottom, top, normal_top, tbot, ttop; char mark; if (!out_buf) { @@ -81,7 +81,8 @@ void ___print_backtrace(unsigned int pir, struct bt_entry *entries, max = *len - 1; bottom = cpu_stack_bottom(pir); - top = cpu_stack_top(pir); + normal_top = cpu_stack_top(pir); + top = cpu_emergency_stack_top(pir); tbot = SKIBOOT_BASE; ttop = (unsigned long)&_etext; @@ -89,6 +90,8 @@ void ___print_backtrace(unsigned int pir, struct bt_entry *entries, for (i = 0; i < count && l < max; i++) { if (entries->sp < bottom || entries->sp > top) mark = '!'; + else if (entries->sp > normal_top) + mark = 'E'; else if (entries->pc < tbot || entries->pc > ttop) mark = '*'; else @@ -162,6 +165,12 @@ void __nomcount __mcount_stack_check(uint64_t sp, uint64_t lr) uint64_t top = base + NORMAL_STACK_SIZE; /* + * Don't check the emergency stack just yet. + */ + if (c->in_opal_call > 1) + return; + + /* * Don't re-enter on this CPU or don't enter at all if somebody * has spotted an overflow */ diff --git a/include/cpu.h b/include/cpu.h index 4a6bc4a..2ca59b9 100644 --- a/include/cpu.h +++ b/include/cpu.h @@ -310,6 +310,7 @@ static inline void cpu_give_self_os(void) extern unsigned long __attrconst cpu_stack_bottom(unsigned int pir); extern unsigned long __attrconst cpu_stack_top(unsigned int pir); +extern unsigned long __attrconst cpu_emergency_stack_top(unsigned int pir); extern void cpu_idle_job(void); extern void cpu_idle_delay(unsigned long delay); diff --git a/include/mem-map.h b/include/mem-map.h index d2bc23f..3e30d9b 100644 --- a/include/mem-map.h +++ b/include/mem-map.h @@ -23,10 +23,10 @@ */ #define SKIBOOT_BASE 0x30000000 -/* Stack size set to 16K, some of it will be used for - * machine check (see stack.h) +/* Stack size set to 32K, 16K for general stack and 16K for an emergency + * stack. */ -#define STACK_SHIFT 14 +#define STACK_SHIFT 15 #define STACK_SIZE (1 << STACK_SHIFT) /* End of the exception region we copy from 0x0. 0x0-0x100 will have @@ -109,7 +109,9 @@ * each stack is STACK_SIZE in size (naturally aligned power of * two) and the bottom of the stack contains the cpu thread * structure for the processor, so it can be obtained by a simple - * bit mask from the stack pointer. + * bit mask from the stack pointer. Within the CPU stack is divided + * into a normal and emergency stack to cope with a single level of + * re-entrancy. * * The size of this array is dynamically determined at boot time */ diff --git a/include/stack.h b/include/stack.h index 4d3e504..a41a4a9 100644 --- a/include/stack.h +++ b/include/stack.h @@ -28,12 +28,19 @@ #define STACK_TOP_GAP 0x100 /* Remaining stack space (gap included) */ -#define NORMAL_STACK_SIZE STACK_SIZE +#define NORMAL_STACK_SIZE (STACK_SIZE/2) + +/* Emergency (re-entry) stack size */ +#define EMERGENCY_STACK_SIZE (STACK_SIZE/2) /* Offset to get to normal CPU stacks */ #define CPU_STACKS_OFFSET (CPU_STACKS_BASE + \ NORMAL_STACK_SIZE - STACK_TOP_GAP) +/* Offset to get to emergency CPU stacks */ +#define EMERGENCY_CPU_STACKS_OFFSET (CPU_STACKS_BASE + NORMAL_STACK_SIZE + \ + EMERGENCY_STACK_SIZE - STACK_TOP_GAP) + /* Gap below the stack. If our stack checker sees the stack below that * gap, it will flag a stack overflow */ |