Messages in this thread | | | Date | Wed, 19 Apr 2023 17:20:38 +0800 | Subject | Re: [PATCH v2] kasan: Fix lockdep report invalid wait context | From | Qi Zheng <> |
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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@intel.com> >>> --- >>> 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
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