| Message ID | 20181207102749.15205-4-bigeasy@linutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm: covert a few spinlock_t locks to raw_spinlock_t | expand |
On 2018-12-07 11:27:49 [+0100], To linux-arm-kernel@lists.infradead.org wrote: > Mostly unwind is done with irqs enabled however SLUB may call it with > irqs disabled while creating a new SLUB cache. > > I had system freeze while loading a module which called > kmem_cache_create() on init. That means SLUB's __slab_alloc() disabled > interrupts and then > > ->new_slab_objects() > ->new_slab() > ->setup_object() > ->setup_object_debug() > ->init_tracking() > ->set_track() > ->save_stack_trace() > ->save_stack_trace_tsk() > ->walk_stackframe() > ->unwind_frame() > ->unwind_find_idx() > =>spin_lock_irqsave(&unwind_lock); > > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> ping Sebastian
On Wed, Feb 13, 2019 at 9:46 AM Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote: > > On 2018-12-07 11:27:49 [+0100], To linux-arm-kernel@lists.infradead.org wrote: > > Mostly unwind is done with irqs enabled however SLUB may call it with > > irqs disabled while creating a new SLUB cache. > > > > I had system freeze while loading a module which called > > kmem_cache_create() on init. That means SLUB's __slab_alloc() disabled > > interrupts and then > > > > ->new_slab_objects() > > ->new_slab() > > ->setup_object() > > ->setup_object_debug() > > ->init_tracking() > > ->set_track() > > ->save_stack_trace() > > ->save_stack_trace_tsk() > > ->walk_stackframe() > > ->unwind_frame() > > ->unwind_find_idx() > > =>spin_lock_irqsave(&unwind_lock); > > > > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > > ping Patches 2/3 and 3/3 look good to me. Can you add them to https://www.arm.linux.org.uk/developer/patches/ ? Reviewed-by: Arnd Bergmann <arnd@arndb.de> Are there any other ARM specific RT patches that are not yet picked up? Arnd
On 2019-02-13 16:14:18 [+0100], Arnd Bergmann wrote: > Patches 2/3 and 3/3 look good to me. Can you add them to > https://www.arm.linux.org.uk/developer/patches/ ? > > Reviewed-by: Arnd Bergmann <arnd@arndb.de> Will do, thanks. > Are there any other ARM specific RT patches that are not yet picked up? No, not at the moment. > Arnd Sebastian
diff --git a/arch/arm/kernel/unwind.c b/arch/arm/kernel/unwind.c index 0bee233fef9a3..314cfb232a635 100644 --- a/arch/arm/kernel/unwind.c +++ b/arch/arm/kernel/unwind.c @@ -93,7 +93,7 @@ extern const struct unwind_idx __start_unwind_idx[]; static const struct unwind_idx *__origin_unwind_idx; extern const struct unwind_idx __stop_unwind_idx[]; -static DEFINE_SPINLOCK(unwind_lock); +static DEFINE_RAW_SPINLOCK(unwind_lock); static LIST_HEAD(unwind_tables); /* Convert a prel31 symbol to an absolute address */ @@ -201,7 +201,7 @@ static const struct unwind_idx *unwind_find_idx(unsigned long addr) /* module unwind tables */ struct unwind_table *table; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_for_each_entry(table, &unwind_tables, list) { if (addr >= table->begin_addr && addr < table->end_addr) { @@ -213,7 +213,7 @@ static const struct unwind_idx *unwind_find_idx(unsigned long addr) break; } } - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); } pr_debug("%s: idx = %p\n", __func__, idx); @@ -529,9 +529,9 @@ struct unwind_table *unwind_table_add(unsigned long start, unsigned long size, tab->begin_addr = text_addr; tab->end_addr = text_addr + text_size; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_add_tail(&tab->list, &unwind_tables); - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); return tab; } @@ -543,9 +543,9 @@ void unwind_table_del(struct unwind_table *tab) if (!tab) return; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_del(&tab->list); - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); kfree(tab); }
Mostly unwind is done with irqs enabled however SLUB may call it with irqs disabled while creating a new SLUB cache. I had system freeze while loading a module which called kmem_cache_create() on init. That means SLUB's __slab_alloc() disabled interrupts and then ->new_slab_objects() ->new_slab() ->setup_object() ->setup_object_debug() ->init_tracking() ->set_track() ->save_stack_trace() ->save_stack_trace_tsk() ->walk_stackframe() ->unwind_frame() ->unwind_find_idx() =>spin_lock_irqsave(&unwind_lock); Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- arch/arm/kernel/unwind.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)