diff options
Diffstat (limited to 'arch/alpha/lib')
| -rw-r--r-- | arch/alpha/lib/io.c | 3 | ||||
| -rw-r--r-- | arch/alpha/lib/stackcheck.S | 27 | ||||
| -rw-r--r-- | arch/alpha/lib/stackkill.S | 35 | ||||
| -rw-r--r-- | arch/alpha/lib/stacktrace.c | 103 |
4 files changed, 167 insertions, 1 deletions
diff --git a/arch/alpha/lib/io.c b/arch/alpha/lib/io.c index 50cc1fe05..4172216d8 100644 --- a/arch/alpha/lib/io.c +++ b/arch/alpha/lib/io.c @@ -477,7 +477,8 @@ void _memset_c_io(unsigned long to, unsigned long c, long count) count -= 4; } - /* Handle all full-sized quadwords: we're aligned (or have a small count) */ + /* Handle all full-sized quadwords: we're aligned + (or have a small count) */ count -= 8; if (count >= 0) { do { diff --git a/arch/alpha/lib/stackcheck.S b/arch/alpha/lib/stackcheck.S new file mode 100644 index 000000000..cc5ce3a5f --- /dev/null +++ b/arch/alpha/lib/stackcheck.S @@ -0,0 +1,27 @@ +/* + * arch/alpha/lib/stackcheck.S + * Contributed by Richard Henderson (rth@tamu.edu) + * + * Verify that we have not overflowed the stack. Oops if we have. + */ + +#include <asm/asm_offsets.h> + + .text + .set noat + + .align 3 + .globl _mcount + .ent _mcount +_mcount: + .frame $30, 0, $28, 0 + .prologue 0 + + lda $0, TASK_SIZE($8) + cmpult $30, $0, $0 + bne $0, 1f + ret ($28) +1: stq $31, -8($31) # oops me, damn it. + br 1b + + .end _mcount diff --git a/arch/alpha/lib/stackkill.S b/arch/alpha/lib/stackkill.S new file mode 100644 index 000000000..e09f2ae1e --- /dev/null +++ b/arch/alpha/lib/stackkill.S @@ -0,0 +1,35 @@ +/* + * arch/alpha/lib/killstack.S + * Contributed by Richard Henderson (rth@cygnus.com) + * + * Clobber the balance of the kernel stack, hoping to catch + * uninitialized local variables in the act. + */ + +#include <asm/asm_offsets.h> + + .text + .set noat + + .align 5 + .globl _mcount + .ent _mcount +_mcount: + .frame $30, 0, $28, 0 + .prologue 0 + + ldi $0, 0xdeadbeef + lda $2, -STACK_SIZE + sll $0, 32, $1 + and $30, $2, $2 + or $0, $1, $0 + lda $2, TASK_SIZE($2) + cmpult $2, $30, $1 + beq $1, 2f +1: stq $0, 0($2) + addq $2, 8, $2 + cmpult $2, $30, $1 + bne $1, 1b +2: ret ($28) + + .end _mcount diff --git a/arch/alpha/lib/stacktrace.c b/arch/alpha/lib/stacktrace.c new file mode 100644 index 000000000..6d432e42a --- /dev/null +++ b/arch/alpha/lib/stacktrace.c @@ -0,0 +1,103 @@ +#include <linux/kernel.h> +#include <asm/system.h> + +typedef unsigned int instr; + +#define MAJOR_OP 0xfc000000 +#define LDA_OP 0x20000000 +#define STQ_OP 0xb4000000 +#define BR_OP 0xc0000000 + +#define STK_ALLOC_1 0x23de8000 /* lda $30,-X($30) */ +#define STK_ALLOC_1M 0xffff8000 +#define STK_ALLOC_2 0x43c0153e /* subq $30,X,$30 */ +#define STK_ALLOC_2M 0xffe01fff + +#define MEM_REG 0x03e00000 +#define MEM_BASE 0x001f0000 +#define MEM_OFF 0x0000ffff +#define MEM_OFF_SIGN 0x00008000 +#define BASE_SP 0x001e0000 + +#define STK_ALLOC_MATCH(INSTR) \ + (((INSTR) & STK_ALLOC_1M) == STK_ALLOC_1 \ + || ((INSTR) & STK_ALLOC_2M) == STK_ALLOC_2) +#define STK_PUSH_MATCH(INSTR) \ + (((INSTR) & (MAJOR_OP | MEM_BASE | MEM_OFF_SIGN)) == (STQ_OP | BASE_SP)) +#define MEM_OP_OFFSET(INSTR) \ + (((long)((INSTR) & MEM_OFF) << 48) >> 48) +#define MEM_OP_REG(INSTR) \ + (((INSTR) & MEM_REG) >> 22) + +/* Branches, jumps, PAL calls, and illegal opcodes end a basic block. */ +#define BB_END(INSTR) \ + (((instr)(INSTR) >= BR_OP) | ((instr)(INSTR) < LDA_OP) | \ + ((((instr)(INSTR) ^ 0x60000000) < 0x20000000) & \ + (((instr)(INSTR) & 0x0c000000) != 0))) + +#define IS_KERNEL_TEXT(PC) ((unsigned long)(PC) > START_ADDR) + +static char reg_name[][4] = { + "v0 ", "t0 ", "t1 ", "t2 ", "t3 ", "t4 ", "t5 ", "t6 ", "t7 ", + "s0 ", "s1 ", "s2 ", "s3 ", "s4 ", "s5 ", "s6 ", "a0 ", "a1 ", + "a2 ", "a3 ", "a4 ", "a5 ", "t8 ", "t9 ", "t10", "t11", "ra ", + "pv ", "at ", "gp ", "sp ", "0" +}; + + +static instr * +display_stored_regs(instr * pro_pc, unsigned char * sp) +{ + instr * ret_pc = 0; + int reg; + unsigned long value; + + printk("Prologue [<%p>], Frame %p:\n", pro_pc, sp); + while (!BB_END(*pro_pc)) + if (STK_PUSH_MATCH(*pro_pc)) { + reg = (*pro_pc & MEM_REG) >> 21; + value = *(unsigned long *)(sp + (*pro_pc & MEM_OFF)); + if (reg == 26) + ret_pc = (instr *)value; + printk("\t\t%s / 0x%016lx\n", reg_name[reg], value); + } + return ret_pc; +} + +static instr * +seek_prologue(instr * pc) +{ + while (!STK_ALLOC_MATCH(*pc)) + --pc; + while (!BB_END(*(pc - 1))) + --pc; + return pc; +} + +static long +stack_increment(instr * prologue_pc) +{ + while (!STK_ALLOC_MATCH(*prologue_pc)) + ++prologue_pc; + + /* Count the bytes allocated. */ + if ((*prologue_pc & STK_ALLOC_1M) == STK_ALLOC_1M) + return -(((long)(*prologue_pc) << 48) >> 48); + else + return (*prologue_pc >> 13) & 0xff; +} + +void +stacktrace(void) +{ + instr * ret_pc; + instr * prologue = (instr *)stacktrace; + register unsigned char * sp __asm__ ("$30"); + + printk("\tstack trace:\n"); + do { + ret_pc = display_stored_regs(prologue, sp); + sp += stack_increment(prologue); + prologue = seek_prologue(ret_pc); + } while (IS_KERNEL_TEXT(ret_pc)); +} |