Re: [PATCH v2] kasan: Fix lockdep report invalid wait context
From: Qi Zheng
Date: Wed Apr 19 2023 - 05:21:21 EST
On 2023/4/19 16:03, Vlastimil Babka wrote:
On 4/19/23 04:52, Qi Zheng wrote:
On 2023/3/27 20:00, Zqiang wrote:
For kernels built with the following options and booting
CONFIG_SLUB=y
CONFIG_DEBUG_LOCKDEP=y
CONFIG_PROVE_LOCKING=y
CONFIG_PROVE_RAW_LOCK_NESTING=y
[ 0.523115] [ BUG: Invalid wait context ]
[ 0.523315] 6.3.0-rc1-yocto-standard+ #739 Not tainted
[ 0.523649] -----------------------------
[ 0.523663] swapper/0/0 is trying to lock:
[ 0.523663] ffff888035611360 (&c->lock){....}-{3:3}, at: put_cpu_partial+0x2e/0x1e0
[ 0.523663] other info that might help us debug this:
[ 0.523663] context-{2:2}
[ 0.523663] no locks held by swapper/0/0.
[ 0.523663] stack backtrace:
[ 0.523663] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.3.0-rc1-yocto-standard+ #739
[ 0.523663] Call Trace:
[ 0.523663] <IRQ>
[ 0.523663] dump_stack_lvl+0x64/0xb0
[ 0.523663] dump_stack+0x10/0x20
[ 0.523663] __lock_acquire+0x6c4/0x3c10
[ 0.523663] lock_acquire+0x188/0x460
[ 0.523663] put_cpu_partial+0x5a/0x1e0
[ 0.523663] __slab_free+0x39a/0x520
[ 0.523663] ___cache_free+0xa9/0xc0
[ 0.523663] qlist_free_all+0x7a/0x160
[ 0.523663] per_cpu_remove_cache+0x5c/0x70
[ 0.523663] __flush_smp_call_function_queue+0xfc/0x330
[ 0.523663] generic_smp_call_function_single_interrupt+0x13/0x20
[ 0.523663] __sysvec_call_function+0x86/0x2e0
[ 0.523663] sysvec_call_function+0x73/0x90
[ 0.523663] </IRQ>
[ 0.523663] <TASK>
[ 0.523663] asm_sysvec_call_function+0x1b/0x20
[ 0.523663] RIP: 0010:default_idle+0x13/0x20
[ 0.523663] RSP: 0000:ffffffff83e07dc0 EFLAGS: 00000246
[ 0.523663] RAX: 0000000000000000 RBX: ffffffff83e1e200 RCX: ffffffff82a83293
[ 0.523663] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8119a6b1
[ 0.523663] RBP: ffffffff83e07dc8 R08: 0000000000000001 R09: ffffed1006ac0d66
[ 0.523663] R10: ffff888035606b2b R11: ffffed1006ac0d65 R12: 0000000000000000
[ 0.523663] R13: ffffffff83e1e200 R14: ffffffff84a7d980 R15: 0000000000000000
[ 0.523663] default_idle_call+0x6c/0xa0
[ 0.523663] do_idle+0x2e1/0x330
[ 0.523663] cpu_startup_entry+0x20/0x30
[ 0.523663] rest_init+0x152/0x240
[ 0.523663] arch_call_rest_init+0x13/0x40
[ 0.523663] start_kernel+0x331/0x470
[ 0.523663] x86_64_start_reservations+0x18/0x40
[ 0.523663] x86_64_start_kernel+0xbb/0x120
[ 0.523663] secondary_startup_64_no_verify+0xe0/0xeb
[ 0.523663] </TASK>
The local_lock_irqsave() is invoked in put_cpu_partial() and happens
in IPI context, due to the CONFIG_PROVE_RAW_LOCK_NESTING=y (the
LD_WAIT_CONFIG not equal to LD_WAIT_SPIN), so acquire local_lock in
IPI context will trigger above calltrace.
Just to add another similar case:
Call Trace:
<IRQ>
dump_stack_lvl+0x69/0x97
__lock_acquire+0x4a0/0x1b50
lock_acquire+0x261/0x2c0
? restore_bytes+0x40/0x40
local_lock_acquire+0x21/0x70
? restore_bytes+0x40/0x40
put_cpu_partial+0x41/0x130
? flush_smp_call_function_queue+0x125/0x4d0
kfree+0x250/0x2c0
flush_smp_call_function_queue+0x125/0x4d0
__sysvec_call_function_single+0x3a/0x100
sysvec_call_function_single+0x4b/0x90
</IRQ>
<TASK>
asm_sysvec_call_function_single+0x16/0x20
So we can't call kfree() and its friends in interrupt context?
We can (well not RT "hard IRQ" context AFAIK, but that shouldn't be the case
here), although I don't see from the part that you posted if it's again
CONFIG_PROVE_RAW_LOCK_NESTING clashing with something else (no KASAN in the
trace or I'm missing it?)
I lost the corresponding vmlinux, but this should be a similar issue, we
should continue to make lockdep recognize the !RT path.
Also +Vlastimil Babka.
Thanks,
Qi
This commit therefore move qlist_free_all() from hard-irq context to
task context.
Signed-off-by: Zqiang <qiang1.zhang@xxxxxxxxx>
---
v1->v2:
Modify the commit information and add Cc.
mm/kasan/quarantine.c | 34 ++++++++--------------------------
1 file changed, 8 insertions(+), 26 deletions(-)
diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c
index 75585077eb6d..152dca73f398 100644
--- a/mm/kasan/quarantine.c
+++ b/mm/kasan/quarantine.c
@@ -99,7 +99,6 @@ static unsigned long quarantine_size;
static DEFINE_RAW_SPINLOCK(quarantine_lock);
DEFINE_STATIC_SRCU(remove_cache_srcu);
-#ifdef CONFIG_PREEMPT_RT
struct cpu_shrink_qlist {
raw_spinlock_t lock;
struct qlist_head qlist;
@@ -108,7 +107,6 @@ struct cpu_shrink_qlist {
static DEFINE_PER_CPU(struct cpu_shrink_qlist, shrink_qlist) = {
.lock = __RAW_SPIN_LOCK_UNLOCKED(shrink_qlist.lock),
};
-#endif
/* Maximum size of the global queue. */
static unsigned long quarantine_max_size;
@@ -319,16 +317,6 @@ static void qlist_move_cache(struct qlist_head *from,
}
}
-#ifndef CONFIG_PREEMPT_RT
-static void __per_cpu_remove_cache(struct qlist_head *q, void *arg)
-{
- struct kmem_cache *cache = arg;
- struct qlist_head to_free = QLIST_INIT;
-
- qlist_move_cache(q, &to_free, cache);
- qlist_free_all(&to_free, cache);
-}
-#else
static void __per_cpu_remove_cache(struct qlist_head *q, void *arg)
{
struct kmem_cache *cache = arg;
@@ -340,7 +328,6 @@ static void __per_cpu_remove_cache(struct qlist_head *q, void *arg)
qlist_move_cache(q, &sq->qlist, cache);
raw_spin_unlock_irqrestore(&sq->lock, flags);
}
-#endif
static void per_cpu_remove_cache(void *arg)
{
@@ -362,6 +349,8 @@ void kasan_quarantine_remove_cache(struct kmem_cache *cache)
{
unsigned long flags, i;
struct qlist_head to_free = QLIST_INIT;
+ int cpu;
+ struct cpu_shrink_qlist *sq;
/*
* Must be careful to not miss any objects that are being moved from
@@ -372,20 +361,13 @@ void kasan_quarantine_remove_cache(struct kmem_cache *cache)
*/
on_each_cpu(per_cpu_remove_cache, cache, 1);
-#ifdef CONFIG_PREEMPT_RT
- {
- int cpu;
- struct cpu_shrink_qlist *sq;
-
- for_each_online_cpu(cpu) {
- sq = per_cpu_ptr(&shrink_qlist, cpu);
- raw_spin_lock_irqsave(&sq->lock, flags);
- qlist_move_cache(&sq->qlist, &to_free, cache);
- raw_spin_unlock_irqrestore(&sq->lock, flags);
- }
- qlist_free_all(&to_free, cache);
+ for_each_online_cpu(cpu) {
+ sq = per_cpu_ptr(&shrink_qlist, cpu);
+ raw_spin_lock_irqsave(&sq->lock, flags);
+ qlist_move_cache(&sq->qlist, &to_free, cache);
+ raw_spin_unlock_irqrestore(&sq->lock, flags);
}
-#endif
+ qlist_free_all(&to_free, cache);
raw_spin_lock_irqsave(&quarantine_lock, flags);
for (i = 0; i < QUARANTINE_BATCHES; i++) {
--
Thanks,
Qi