[Crash-utility] [PATCH] s390: Fix backtrace code

Hi Dave, This patch fixes several bugs in the s390 stack backtrace code * Add panic stack as second interrupt stack * Fix printing of access registers (4 bytes instead of 8 bytes) * Use u64 for s390x register 14 * Fix interrupt stack handling for s390x (use 160 byte overhead instead of 96) --- s390.c | 46 ++++++++++++++++++------------- s390x.c | 94 +++++++++++++++++++++++++++++++++++----------------------------- 2 files changed, 79 insertions(+), 61 deletions(-) --- a/s390.c +++ b/s390.c @@ -37,7 +37,7 @@ #define S390_PTE_INVALID_MASK 0x80000900 #define S390_PTE_INVALID(x) ((x) & S390_PTE_INVALID_MASK) -#define ASYNC_STACK_SIZE STACKSIZE() // can be 4096 or 8192 +#define INT_STACK_SIZE STACKSIZE() // can be 4096 or 8192 #define KERNEL_STACK_SIZE STACKSIZE() // can be 4096 or 8192 #define LOWCORE_SIZE 4096 @@ -570,20 +570,21 @@ s390_get_lowcore(int cpu, char* lowcore) FAULT_ON_ERROR); } -/* - * read in the async stack +/* + * Read interrupt stack (either "async_stack" or "panic_stack"); */ -static void -s390_get_async_stack(char* lowcore, char* async_stack, unsigned long* start, unsigned long* end) +static void s390_get_int_stack(char *stack_name, char* lc, char* int_stack, + unsigned long* start, unsigned long* end) { - unsigned long async_stack_ptr; + unsigned long stack_addr; - async_stack_ptr = ULONG(lowcore + - MEMBER_OFFSET("_lowcore","async_stack")); - readmem(async_stack_ptr-ASYNC_STACK_SIZE,KVADDR, async_stack, - ASYNC_STACK_SIZE, "async_stack", FAULT_ON_ERROR); - *start=async_stack_ptr-ASYNC_STACK_SIZE; - *end=async_stack_ptr; + if (!MEMBER_EXISTS("_lowcore", stack_name)) + return; + stack_addr = ULONG(lc + MEMBER_OFFSET("_lowcore", stack_name)); + readmem(stack_addr - INT_STACK_SIZE, KVADDR, int_stack, + INT_STACK_SIZE, stack_name, FAULT_ON_ERROR); + *start = stack_addr - INT_STACK_SIZE; + *end = stack_addr; } /* @@ -593,16 +594,18 @@ static void s390_back_trace_cmd(struct bt_info *bt) { char* stack; - char async_stack[ASYNC_STACK_SIZE]; + char async_stack[INT_STACK_SIZE]; + char panic_stack[INT_STACK_SIZE]; long ksp,backchain,old_backchain; int i=0, r14_offset,bc_offset,r14, skip_first_frame=0; - unsigned long async_start,async_end, stack_end, stack_start, stack_base; + unsigned long async_start = 0, async_end = 0; + unsigned long panic_start = 0, panic_end = 0; + unsigned long stack_end, stack_start, stack_base; if (bt->hp && bt->hp->eip) { error(WARNING, "instruction pointer argument ignored on this architecture!\n"); } - async_end = async_start = 0; ksp = bt->stkptr; /* print lowcore and get async stack when task has cpu */ @@ -622,9 +625,10 @@ s390_back_trace_cmd(struct bt_info *bt) s390_print_lowcore(lowcore,bt,0); return; } - - s390_get_async_stack(lowcore,async_stack,&async_start, - &async_end); + s390_get_int_stack("async_stack", lowcore, async_stack, + &async_start, &async_end); + s390_get_int_stack("panic_stack", lowcore, panic_stack, + &panic_start, &panic_end); s390_print_lowcore(lowcore,bt,1); fprintf(fp,"\n"); skip_first_frame=1; @@ -653,7 +657,7 @@ s390_back_trace_cmd(struct bt_info *bt) unsigned long r14_stack_off; int j; - /* Find stack: Either async stack or task stack */ + /* Find stack: Either async, panic stack or task stack */ if((backchain > stack_start) && (backchain < stack_end)){ stack = bt->stackbuf; stack_base = stack_start; @@ -661,6 +665,10 @@ s390_back_trace_cmd(struct bt_info *bt) && s390_has_cpu(bt)){ stack = async_stack; stack_base = async_start; + } else if((backchain > panic_start) && (backchain < panic_end) + && s390_has_cpu(bt)){ + stack = panic_stack; + stack_base = panic_start; } else { /* invalid stackframe */ break; --- a/s390x.c +++ b/s390x.c @@ -36,7 +36,7 @@ #define S390X_PTE_INVALID_MASK 0x900ULL #define S390X_PTE_INVALID(x) ((x) & S390X_PTE_INVALID_MASK) -#define ASYNC_STACK_SIZE STACKSIZE() // can be 8192 or 16384 +#define INT_STACK_SIZE STACKSIZE() // can be 8192 or 16384 #define KERNEL_STACK_SIZE STACKSIZE() // can be 8192 or 16384 #define LOWCORE_SIZE 8192 @@ -803,19 +803,20 @@ s390x_get_lowcore(struct bt_info *bt, ch } /* - * read in the async stack + * Read interrupt stack (either "async_stack" or "panic_stack"); */ -static void -s390x_get_async_stack(char* lowcore, char* async_stack, unsigned long* start, unsigned long* end) +static void s390x_get_int_stack(char *stack_name, char* lc, char* int_stack, + unsigned long* start, unsigned long* end) { - unsigned long async_stack_ptr; + unsigned long stack_addr; - async_stack_ptr = ULONG(lowcore + - MEMBER_OFFSET("_lowcore","async_stack")); - readmem(async_stack_ptr-ASYNC_STACK_SIZE,KVADDR, async_stack, - ASYNC_STACK_SIZE, "async_stack", FAULT_ON_ERROR); - *start=async_stack_ptr-ASYNC_STACK_SIZE; - *end=async_stack_ptr; + if (!MEMBER_EXISTS("_lowcore", stack_name)) + return; + stack_addr = ULONG(lc + MEMBER_OFFSET("_lowcore", stack_name)); + readmem(stack_addr - INT_STACK_SIZE, KVADDR, int_stack, + INT_STACK_SIZE, stack_name, FAULT_ON_ERROR); + *start = stack_addr - INT_STACK_SIZE; + *end = stack_addr; } /* @@ -825,11 +826,14 @@ static void s390x_back_trace_cmd(struct bt_info *bt) { char* stack; - char async_stack[ASYNC_STACK_SIZE]; + char async_stack[INT_STACK_SIZE]; + char panic_stack[INT_STACK_SIZE]; long ksp,backchain,old_backchain; - int i=0, r14_offset,bc_offset,r14, skip_first_frame=0; + int i=0, r14_offset,bc_offset, skip_first_frame=0; unsigned long async_start = 0, async_end = 0; + unsigned long panic_start = 0, panic_end = 0; unsigned long stack_end, stack_start, stack_base; + unsigned long r14; if (bt->hp && bt->hp->eip) { error(WARNING, @@ -854,9 +858,10 @@ s390x_back_trace_cmd(struct bt_info *bt) s390x_print_lowcore(lowcore,bt,0); return; } - - s390x_get_async_stack(lowcore,async_stack,&async_start, - &async_end); + s390x_get_int_stack("async_stack", lowcore, async_stack, + &async_start, &async_end); + s390x_get_int_stack("panic_stack", lowcore, panic_stack, + &panic_start, &panic_end); s390x_print_lowcore(lowcore,bt,1); fprintf(fp,"\n"); skip_first_frame=1; @@ -885,7 +890,7 @@ s390x_back_trace_cmd(struct bt_info *bt) unsigned long r14_stack_off; int j; - /* Find stack: Either async stack or task stack */ + /* Find stack: Either async, panic stack or task stack */ if((backchain > stack_start) && (backchain < stack_end)){ stack = bt->stackbuf; stack_base = stack_start; @@ -893,6 +898,10 @@ s390x_back_trace_cmd(struct bt_info *bt) && s390x_has_cpu(bt)){ stack = async_stack; stack_base = async_start; + } else if((backchain > panic_start) && (backchain < panic_end) + && s390x_has_cpu(bt)){ + stack = panic_stack; + stack_base = panic_start; } else { /* invalid stackframe */ break; @@ -913,7 +922,7 @@ s390x_back_trace_cmd(struct bt_info *bt) skip_first_frame=0; } else { fprintf(fp," #%i [%08lx] ",i,backchain); - fprintf(fp,"%s at %x\n", closest_symbol(r14), r14); + fprintf(fp,"%s at %lx\n", closest_symbol(r14), r14); if (bt->flags & BT_LINE_NUMBERS) s390x_dump_line_number(r14); i++; @@ -944,19 +953,20 @@ s390x_back_trace_cmd(struct bt_info *bt) } /* Check for interrupt stackframe */ - if((backchain == 0) && (stack == async_stack)){ - unsigned long psw_flags,r15; + if((backchain == 0) && + (stack == async_stack || stack == panic_stack)) { + int pt_regs_off = old_backchain - stack_base + 160; + unsigned long psw_flags; - psw_flags = ULONG(&stack[old_backchain - stack_base - +96 +MEMBER_OFFSET("pt_regs","psw")]); + psw_flags = ULONG(&stack[pt_regs_off + + MEMBER_OFFSET("pt_regs", "psw")]); if(psw_flags & 0x1000000000000ULL){ /* User psw: should not happen */ break; } - r15 = ULONG(&stack[old_backchain - stack_base + - 96 + MEMBER_OFFSET("pt_regs", - "gprs") + 15 * S390X_WORD_SIZE]); - backchain=r15; + backchain = ULONG(&stack[pt_regs_off + + MEMBER_OFFSET("pt_regs", "gprs") + + 15 * S390X_WORD_SIZE]); fprintf(fp," - Interrupt -\n"); } } while(backchain != 0); @@ -1036,28 +1046,28 @@ s390x_print_lowcore(char* lc, struct bt_ fprintf(fp," -access registers:\n"); ptr = lc + MEMBER_OFFSET("_lowcore","access_regs_save_area"); - tmp[0]=ULONG(ptr); - tmp[1]=ULONG(ptr + 4); - tmp[2]=ULONG(ptr + 2 * 4); - tmp[3]=ULONG(ptr + 3 * 4); + tmp[0]=UINT(ptr); + tmp[1]=UINT(ptr + 4); + tmp[2]=UINT(ptr + 2 * 4); + tmp[3]=UINT(ptr + 3 * 4); fprintf(fp," %#010lx %#010lx %#010lx %#010lx\n", tmp[0], tmp[1], tmp[2], tmp[3]); - tmp[0]=ULONG(ptr + 4 * 4); - tmp[1]=ULONG(ptr + 5 * 4); - tmp[2]=ULONG(ptr + 6 * 4); - tmp[3]=ULONG(ptr + 7 * 4); + tmp[0]=UINT(ptr + 4 * 4); + tmp[1]=UINT(ptr + 5 * 4); + tmp[2]=UINT(ptr + 6 * 4); + tmp[3]=UINT(ptr + 7 * 4); fprintf(fp," %#010lx %#010lx %#010lx %#010lx\n", tmp[0], tmp[1], tmp[2], tmp[3]); - tmp[0]=ULONG(ptr + 8 * 4); - tmp[1]=ULONG(ptr + 9 * 4); - tmp[2]=ULONG(ptr + 10* 4); - tmp[3]=ULONG(ptr + 11* 4); + tmp[0]=UINT(ptr + 8 * 4); + tmp[1]=UINT(ptr + 9 * 4); + tmp[2]=UINT(ptr + 10 * 4); + tmp[3]=UINT(ptr + 11 * 4); fprintf(fp," %#010lx %#010lx %#010lx %#010lx\n", tmp[0], tmp[1], tmp[2], tmp[3]); - tmp[0]=ULONG(ptr + 12* 4); - tmp[1]=ULONG(ptr + 13* 4); - tmp[2]=ULONG(ptr + 14* 4); - tmp[3]=ULONG(ptr + 15* 4); + tmp[0]=UINT(ptr + 12 * 4); + tmp[1]=UINT(ptr + 13 * 4); + tmp[2]=UINT(ptr + 14 * 4); + tmp[3]=UINT(ptr + 15 * 4); fprintf(fp," %#010lx %#010lx %#010lx %#010lx\n", tmp[0], tmp[1], tmp[2], tmp[3]);