kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

locking/lockdep: Improve 'invalid wait context' splat

Browse source 
The 'invalid wait context' splat doesn't print all the information
required to reconstruct / validate the error, specifically the
irq-context state is missing.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Peter Zijlstra 2020-03-31 20:38:12 +02:00 committed by Ingo Molnar
parent a13f58a0ca
commit 9a019db0b6
1 changed files with 31 additions and 20 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

51
kernel/locking/lockdep.c
View file

@ -3952,10 +3952,36 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this,
return ret;
}
static inline short task_wait_context(struct task_struct *curr)
{
/*
* Set appropriate wait type for the context; for IRQs we have to take
* into account force_irqthread as that is implied by PREEMPT_RT.
*/
if (curr->hardirq_context) {
/*
* Check if force_irqthreads will run us threaded.
*/
if (curr->hardirq_threaded || curr->irq_config)
return LD_WAIT_CONFIG;
return LD_WAIT_SPIN;
} else if (curr->softirq_context) {
/*
* Softirqs are always threaded.
*/
return LD_WAIT_CONFIG;
}
return LD_WAIT_MAX;
}
static int
print_lock_invalid_wait_context(struct task_struct *curr,
struct held_lock *hlock)
{
short curr_inner;
if (!debug_locks_off())
return 0;
if (debug_locks_silent)
@ -3971,6 +3997,10 @@ print_lock_invalid_wait_context(struct task_struct *curr,
print_lock(hlock);
pr_warn("other info that might help us debug this:\n");
curr_inner = task_wait_context(curr);
pr_warn("context-{%d:%d}\n", curr_inner, curr_inner);
lockdep_print_held_locks(curr);
pr_warn("stack backtrace:\n");
@ -4017,26 +4047,7 @@ static int check_wait_context(struct task_struct *curr, struct held_lock *next)
}
depth++;
/*
* Set appropriate wait type for the context; for IRQs we have to take
* into account force_irqthread as that is implied by PREEMPT_RT.
*/
if (curr->hardirq_context) {
/*
* Check if force_irqthreads will run us threaded.
*/
if (curr->hardirq_threaded || curr->irq_config)
curr_inner = LD_WAIT_CONFIG;
else
curr_inner = LD_WAIT_SPIN;
} else if (curr->softirq_context) {
/*
* Softirqs are always threaded.
*/
curr_inner = LD_WAIT_CONFIG;
} else {
curr_inner = LD_WAIT_MAX;
}
curr_inner = task_wait_context(curr);
for (; depth < curr->lockdep_depth; depth++) {
struct held_lock *prev = curr->held_locks + depth;