From d0208639dbc6fe97a25054df44faa2d19aca9380 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 17 Oct 2016 11:08:31 +0200 Subject: s390/dumpstack: restore reliable indicator for call traces Before merging all different stack tracers the call traces printed had an indicator if an entry can be considered reliable or not. Unreliable entries were put in braces, reliable not. Currently all lines contain these extra braces. This patch restores the old behaviour by adding an extra "reliable" parameter to the callback functions. Only show_trace makes currently use of it. Before: [ 0.804751] Call Trace: [ 0.804753] ([<000000000017d0e0>] try_to_wake_up+0x318/0x5e0) [ 0.804756] ([<0000000000161d64>] create_worker+0x174/0x1c0) After: [ 0.804751] Call Trace: [ 0.804753] ([<000000000017d0e0>] try_to_wake_up+0x318/0x5e0) [ 0.804756] [<0000000000161d64>] create_worker+0x174/0x1c0 Fixes: 758d39ebd3d5 ("s390/dumpstack: merge all four stack tracers") Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/dumpstack.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'arch/s390/kernel/dumpstack.c') diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c index 6693383bc01b..518f615ad0a2 100644 --- a/arch/s390/kernel/dumpstack.c +++ b/arch/s390/kernel/dumpstack.c @@ -38,10 +38,10 @@ __dump_trace(dump_trace_func_t func, void *data, unsigned long sp, if (sp < low || sp > high - sizeof(*sf)) return sp; sf = (struct stack_frame *) sp; + if (func(data, sf->gprs[8], 0)) + return sp; /* Follow the backchain. */ while (1) { - if (func(data, sf->gprs[8])) - return sp; low = sp; sp = sf->back_chain; if (!sp) @@ -49,6 +49,8 @@ __dump_trace(dump_trace_func_t func, void *data, unsigned long sp, if (sp <= low || sp > high - sizeof(*sf)) return sp; sf = (struct stack_frame *) sp; + if (func(data, sf->gprs[8], 1)) + return sp; } /* Zero backchain detected, check for interrupt frame. */ sp = (unsigned long) (sf + 1); @@ -56,7 +58,7 @@ __dump_trace(dump_trace_func_t func, void *data, unsigned long sp, return sp; regs = (struct pt_regs *) sp; if (!user_mode(regs)) { - if (func(data, regs->psw.addr)) + if (func(data, regs->psw.addr, 1)) return sp; } low = sp; @@ -90,7 +92,7 @@ struct return_address_data { int depth; }; -static int __return_address(void *data, unsigned long address) +static int __return_address(void *data, unsigned long address, int reliable) { struct return_address_data *rd = data; @@ -109,9 +111,12 @@ unsigned long return_address(int depth) } EXPORT_SYMBOL_GPL(return_address); -static int show_address(void *data, unsigned long address) +static int show_address(void *data, unsigned long address, int reliable) { - printk("([<%016lx>] %pSR)\n", address, (void *)address); + if (reliable) + printk(" [<%016lx>] %pSR \n", address, (void *)address); + else + printk("([<%016lx>] %pSR)\n", address, (void *)address); return 0; } -- cgit v1.2.3 From a790634544f5f98364b0aafe9d7e669810d96360 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 17 Oct 2016 11:59:58 +0200 Subject: s390/dumpstack: use pr_cont where appropriate Use pr_cont instead of simple printk calls when lines will be continued. This fixes the kernel output of various lines printed on e.g. a warning: Before: [ 0.840604] Krnl PSW : 0404c00180000000 000000000017d1d2 [ 0.840606] (try_to_wake_up+0x382/0x5e0) [ 0.840610] R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 [ 0.840611] RI:0 EA:3 After: [ 0.831772] Krnl PSW : 0404c00180000000 000000000017d14a (try_to_wake_up+0x382/0x5e0) [ 0.831776] R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3 Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/dumpstack.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/s390/kernel/dumpstack.c') diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c index 518f615ad0a2..4bebe72b7780 100644 --- a/arch/s390/kernel/dumpstack.c +++ b/arch/s390/kernel/dumpstack.c @@ -168,13 +168,13 @@ void show_registers(struct pt_regs *regs) mode = user_mode(regs) ? "User" : "Krnl"; printk("%s PSW : %p %p", mode, (void *)regs->psw.mask, (void *)regs->psw.addr); if (!user_mode(regs)) - printk(" (%pSR)", (void *)regs->psw.addr); - printk("\n"); + pr_cont(" (%pSR)", (void *)regs->psw.addr); + pr_cont("\n"); printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x " "P:%x AS:%x CC:%x PM:%x", psw->r, psw->t, psw->i, psw->e, psw->key, psw->m, psw->w, psw->p, psw->as, psw->cc, psw->pm); - printk(" RI:%x EA:%x", psw->ri, psw->eaba); - printk("\n%s GPRS: %016lx %016lx %016lx %016lx\n", mode, + pr_cont(" RI:%x EA:%x\n", psw->ri, psw->eaba); + printk("%s GPRS: %016lx %016lx %016lx %016lx\n", mode, regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]); printk(" %016lx %016lx %016lx %016lx\n", regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]); -- cgit v1.2.3 From dcddba96cdbc5d0e4d4a17bf22cfd9b2f038a4ca Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 17 Oct 2016 13:07:46 +0200 Subject: s390/dumpstack: get rid of return_address again With commit ef6000b4c670 ("Disable the __builtin_return_address() warning globally after all)" the kernel does not warn at all again if __builtin_return_address(n) is called with n > 0. Besides the fact that this was a false warning on s390 anyway, due to the always present backchain, we can now revert commit 5606330627ab ("s390/dumpstack: implement and use return_address()") again, to simplify the code again. After all I shouldn't have had return_address() implememted at all to workaround this issue. So get rid of this again. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/ftrace.h | 4 +--- arch/s390/kernel/dumpstack.c | 24 ------------------------ 2 files changed, 1 insertion(+), 27 deletions(-) (limited to 'arch/s390/kernel/dumpstack.c') diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h index 64053d9ac3f2..836c56290499 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -12,9 +12,7 @@ #ifndef __ASSEMBLY__ -unsigned long return_address(int depth); - -#define ftrace_return_address(n) return_address(n) +#define ftrace_return_address(n) __builtin_return_address(n) void _mcount(void); void ftrace_caller(void); diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c index 4bebe72b7780..34345c0a3c46 100644 --- a/arch/s390/kernel/dumpstack.c +++ b/arch/s390/kernel/dumpstack.c @@ -87,30 +87,6 @@ void dump_trace(dump_trace_func_t func, void *data, struct task_struct *task, } EXPORT_SYMBOL_GPL(dump_trace); -struct return_address_data { - unsigned long address; - int depth; -}; - -static int __return_address(void *data, unsigned long address, int reliable) -{ - struct return_address_data *rd = data; - - if (rd->depth--) - return 0; - rd->address = address; - return 1; -} - -unsigned long return_address(int depth) -{ - struct return_address_data rd = { .depth = depth + 2 }; - - dump_trace(__return_address, &rd, NULL, current_stack_pointer()); - return rd.address; -} -EXPORT_SYMBOL_GPL(return_address); - static int show_address(void *data, unsigned long address, int reliable) { if (reliable) -- cgit v1.2.3 From 47ece7fef4e4206cdcee7c28ac3bca3ede0a1908 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Wed, 19 Oct 2016 13:42:55 +0200 Subject: s390/dumpstack: use pr_cont within show_stack and die Use pr_cont instead of printk calls also within show_stack and die in order to avoid extra line breaks. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/dumpstack.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'arch/s390/kernel/dumpstack.c') diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c index 34345c0a3c46..55d4fe174fd9 100644 --- a/arch/s390/kernel/dumpstack.c +++ b/arch/s390/kernel/dumpstack.c @@ -119,14 +119,14 @@ void show_stack(struct task_struct *task, unsigned long *sp) else stack = (unsigned long *)task->thread.ksp; } + printk(KERN_DEFAULT "Stack:\n"); for (i = 0; i < 20; i++) { if (((addr_t) stack & (THREAD_SIZE-1)) == 0) break; - if ((i * sizeof(long) % 32) == 0) - printk("%s ", i == 0 ? "" : "\n"); - printk("%016lx ", *stack++); + if (i % 4 == 0) + printk(KERN_DEFAULT " "); + pr_cont("%016lx%c", *stack++, i % 4 == 3 ? '\n' : ' '); } - printk("\n"); show_trace(task, (unsigned long)sp); } @@ -186,14 +186,14 @@ void die(struct pt_regs *regs, const char *str) printk("%s: %04x ilc:%d [#%d] ", str, regs->int_code & 0xffff, regs->int_code >> 17, ++die_counter); #ifdef CONFIG_PREEMPT - printk("PREEMPT "); + pr_cont("PREEMPT "); #endif #ifdef CONFIG_SMP - printk("SMP "); + pr_cont("SMP "); #endif if (debug_pagealloc_enabled()) - printk("DEBUG_PAGEALLOC"); - printk("\n"); + pr_cont("DEBUG_PAGEALLOC"); + pr_cont("\n"); notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV); print_modules(); show_regs(regs); -- cgit v1.2.3