[PATCHv2 01/50] kallsyms/printk: Add loglvl to print_ip_sym()

From: Dmitry Safonov
Date: Mon Mar 16 2020 - 10:39:51 EST


print_ip_sym() needs to have a log level parameter to comply with other
parts being printed. Otherwise, half of the expected backtrace would be
printed and other may be missing with some logging level.

The following callee(s) are using now the adjusted log level:
- microblaze/unwind: the same level as headers & userspace unwind.
Note that pr_debug()'s there are for debugging the unwinder itself.
- nds32/traps: symbol addresses are printed with the same log level
as backtrace headers.
- lockdep: ip for locking issues is printed with the same log level
as other part of the warning.
- sched: ip where preemption was disabled is printed as error like
the rest part of the message.
- ftrace: bug reports are now consistent in the log level being used.

Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx>
Cc: Ben Segall <bsegall@xxxxxxxxxx>
Cc: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
Cc: Greentime Hu <green.hu@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: James Hogan <jhogan@xxxxxxxxxx>
Cc: Juri Lelli <juri.lelli@xxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Michal Simek <monstr@xxxxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx>
Cc: Paul Burton <paulburton@xxxxxxxxxx>
Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Vincent Chen <deanbo422@xxxxxxxxx>
Cc: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxxx
Cc: linux-riscv@xxxxxxxxxxxxxxxxxxx
Acked-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: Dmitry Safonov <dima@xxxxxxxxxx>
---
arch/microblaze/kernel/unwind.c | 2 +-
arch/mips/kernel/traps.c | 4 ++--
arch/nds32/kernel/traps.c | 4 ++--
arch/riscv/kernel/stacktrace.c | 2 +-
include/linux/kallsyms.h | 4 ++--
kernel/locking/lockdep.c | 4 ++--
kernel/sched/core.c | 6 ++----
kernel/trace/ftrace.c | 8 ++++----
tools/include/linux/kallsyms.h | 2 +-
9 files changed, 17 insertions(+), 19 deletions(-)

diff --git a/arch/microblaze/kernel/unwind.c b/arch/microblaze/kernel/unwind.c
index 34c270cb11fc..4241cdd28ee7 100644
--- a/arch/microblaze/kernel/unwind.c
+++ b/arch/microblaze/kernel/unwind.c
@@ -254,7 +254,7 @@ static void microblaze_unwind_inner(struct task_struct *task,
task->comm);
break;
} else
- print_ip_sym(pc);
+ print_ip_sym(KERN_INFO, pc);
}

/* Stop when we reach anything not part of the kernel */
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 31968cbd6464..de05503c680c 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -123,7 +123,7 @@ static void show_raw_backtrace(unsigned long reg29)
break;
}
if (__kernel_text_address(addr))
- print_ip_sym(addr);
+ print_ip_sym(KERN_DEFAULT, addr);
}
printk("\n");
}
@@ -153,7 +153,7 @@ static void show_backtrace(struct task_struct *task, const struct pt_regs *regs)
}
printk("Call Trace:\n");
do {
- print_ip_sym(pc);
+ print_ip_sym(KERN_DEFAULT, pc);
pc = unwind_stack(task, &sp, pc, &ra);
} while (pc);
pr_cont("\n");
diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c
index f4d386b52622..40625760a125 100644
--- a/arch/nds32/kernel/traps.c
+++ b/arch/nds32/kernel/traps.c
@@ -108,7 +108,7 @@ static void __dump(struct task_struct *tsk, unsigned long *base_reg)
if (__kernel_text_address(ret_addr)) {
ret_addr = ftrace_graph_ret_addr(
tsk, &graph, ret_addr, NULL);
- print_ip_sym(ret_addr);
+ print_ip_sym(KERN_EMERG, ret_addr);
}
if (--cnt < 0)
break;
@@ -124,7 +124,7 @@ static void __dump(struct task_struct *tsk, unsigned long *base_reg)

ret_addr = ftrace_graph_ret_addr(
tsk, &graph, ret_addr, NULL);
- print_ip_sym(ret_addr);
+ print_ip_sym(KERN_EMERG, ret_addr);
}
if (--cnt < 0)
break;
diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c
index 0940681d2f68..a76892b48fff 100644
--- a/arch/riscv/kernel/stacktrace.c
+++ b/arch/riscv/kernel/stacktrace.c
@@ -98,7 +98,7 @@ static void notrace walk_stackframe(struct task_struct *task,

static bool print_trace_address(unsigned long pc, void *arg)
{
- print_ip_sym(pc);
+ print_ip_sym(KERN_DEFAULT, pc);
return false;
}

diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h
index 657a83b943f0..98338dc6b5d2 100644
--- a/include/linux/kallsyms.h
+++ b/include/linux/kallsyms.h
@@ -165,9 +165,9 @@ static inline int kallsyms_show_value(void)

#endif /*CONFIG_KALLSYMS*/

-static inline void print_ip_sym(unsigned long ip)
+static inline void print_ip_sym(const char *loglvl, unsigned long ip)
{
- printk("[<%px>] %pS\n", (void *) ip, (void *) ip);
+ printk("%s[<%px>] %pS\n", loglvl, (void *) ip, (void *) ip);
}

#endif /*_LINUX_KALLSYMS_H*/
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 32406ef0d6a2..af819bb6874b 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -3998,7 +3998,7 @@ static void print_unlock_imbalance_bug(struct task_struct *curr,
curr->comm, task_pid_nr(curr));
print_lockdep_cache(lock);
pr_cont(") at:\n");
- print_ip_sym(ip);
+ print_ip_sym(KERN_WARNING, ip);
pr_warn("but there are no more locks to release!\n");
pr_warn("\nother info that might help us debug this:\n");
lockdep_print_held_locks(curr);
@@ -4600,7 +4600,7 @@ static void print_lock_contention_bug(struct task_struct *curr,
curr->comm, task_pid_nr(curr));
print_lockdep_cache(lock);
pr_cont(") at:\n");
- print_ip_sym(ip);
+ print_ip_sym(KERN_WARNING, ip);
pr_warn("but there are no locks held!\n");
pr_warn("\nother info that might help us debug this:\n");
lockdep_print_held_locks(curr);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 1a9983da4408..2284deb3a83b 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3858,8 +3858,7 @@ static noinline void __schedule_bug(struct task_struct *prev)
if (IS_ENABLED(CONFIG_DEBUG_PREEMPT)
&& in_atomic_preempt_off()) {
pr_err("Preemption disabled at:");
- print_ip_sym(preempt_disable_ip);
- pr_cont("\n");
+ print_ip_sym(KERN_ERR, preempt_disable_ip);
}
if (panic_on_warn)
panic("scheduling while atomic\n");
@@ -6792,8 +6791,7 @@ void ___might_sleep(const char *file, int line, int preempt_offset)
if (IS_ENABLED(CONFIG_DEBUG_PREEMPT)
&& !preempt_count_equals(preempt_offset)) {
pr_err("Preemption disabled at:");
- print_ip_sym(preempt_disable_ip);
- pr_cont("\n");
+ print_ip_sym(KERN_ERR, preempt_disable_ip);
}
dump_stack();
add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index fd81c7de77a7..c377e290ba54 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2021,12 +2021,12 @@ void ftrace_bug(int failed, struct dyn_ftrace *rec)
case -EFAULT:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on modifying ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
break;
case -EINVAL:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace failed to modify ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
print_ip_ins(" actual: ", (unsigned char *)ip);
pr_cont("\n");
if (ftrace_expected) {
@@ -2037,12 +2037,12 @@ void ftrace_bug(int failed, struct dyn_ftrace *rec)
case -EPERM:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on writing ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
break;
default:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on unknown error ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
}
print_bug_type();
if (rec) {
diff --git a/tools/include/linux/kallsyms.h b/tools/include/linux/kallsyms.h
index 89ca6fe257cc..efb6c3f5f2a9 100644
--- a/tools/include/linux/kallsyms.h
+++ b/tools/include/linux/kallsyms.h
@@ -20,7 +20,7 @@ static inline const char *kallsyms_lookup(unsigned long addr,

#include <execinfo.h>
#include <stdlib.h>
-static inline void print_ip_sym(unsigned long ip)
+static inline void print_ip_sym(const char *loglvl, unsigned long ip)
{
char **name;

--
2.25.1