This is a note to let you know that I've just added the patch titled
regmap: introduce regmap_name to fix syscon regmap trace events
to the 3.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
regmap-introduce-regmap_name-to-fix-syscon-regmap-trace-events.patch
and it can be found in the queue-3.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From c6b570d97c0e77f570bb6b2ed30d372b2b1e9aae Mon Sep 17 00:00:00 2001
From: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
Date: Mon, 9 Mar 2015 12:20:13 +0100
Subject: regmap: introduce regmap_name to fix syscon regmap trace events
From: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
commit c6b570d97c0e77f570bb6b2ed30d372b2b1e9aae upstream.
This patch fixes a NULL pointer dereference when enabling regmap event
tracing in the presence of a syscon regmap, introduced by commit bdb0066df96e
("mfd: syscon: Decouple syscon interface from platform devices").
That patch introduced syscon regmaps that have their dev field set to NULL.
The regmap trace events expect it to point to a valid struct device and feed
it to dev_name():
$ echo 1 > /sys/kernel/debug/tracing/events/regmap/enable
Unable to handle kernel NULL pointer dereference at virtual address 0000002c
pgd = 80004000
[0000002c] *pgd=00000000
Internal error: Oops: 17 [#1] SMP ARM
Modules linked in: coda videobuf2_vmalloc
CPU: 0 PID: 304 Comm: kworker/0:2 Not tainted 4.0.0-rc2+ #9197
Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
Workqueue: events_freezable thermal_zone_device_check
task: 9f25a200 ti: 9f1ee000 task.ti: 9f1ee000
PC is at ftrace_raw_event_regmap_block+0x3c/0xe4
LR is at _regmap_raw_read+0x1bc/0x1cc
pc : [<803636e8>] lr : [<80365f2c>] psr: 600f0093
sp : 9f1efd78 ip : 9f1efdb8 fp : 9f1efdb4
r10: 00000004 r9 : 00000001 r8 : 00000001
r7 : 00000180 r6 : 00000000 r5 : 9f00e3c0 r4 : 00000003
r3 : 00000001 r2 : 00000180 r1 : 00000000 r0 : 9f00e3c0
Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel
Control: 10c5387d Table: 2d91004a DAC: 00000015
Process kworker/0:2 (pid: 304, stack limit = 0x9f1ee210)
Stack: (0x9f1efd78 to 0x9f1f0000)
fd60: 9f1efda4 9f1efd88
fd80: 800708c0 805f9510 80927140 800f0013 9f1fc800 9eb2f490 00000000 00000180
fda0: 808e3840 00000001 9f1efdfc 9f1efdb8 80365f2c 803636b8 805f8958 800708e0
fdc0: a00f0013 803636ac 9f16de00 00000180 80927140 9f1fc800 9f1fc800 9f1efe6c
fde0: 9f1efe6c 9f732400 00000000 00000000 9f1efe1c 9f1efe00 80365f70 80365d7c
fe00: 80365f3c 9f1fc800 9f1fc800 00000180 9f1efe44 9f1efe20 803656a4 80365f48
fe20: 9f1fc800 00000180 9f1efe6c 9f1efe6c 9f732400 00000000 9f1efe64 9f1efe48
fe40: 803657bc 80365634 00000001 9e95f910 9f1fc800 9f1efeb4 9f1efe8c 9f1efe68
fe60: 80452ac0 80365778 9f1efe8c 9f1efe78 9e93d400 9e93d5e8 9f1efeb4 9f72ef40
fe80: 9f1efeac 9f1efe90 8044e11c 80452998 8045298c 9e93d608 9e93d400 808e1978
fea0: 9f1efecc 9f1efeb0 8044fd14 8044e0d0 ffffffff 9f25a200 9e93d608 9e481380
fec0: 9f1efedc 9f1efed0 8044fde8 8044fcec 9f1eff1c 9f1efee0 80038d50 8044fdd8
fee0: 9f1ee020 9f72ef40 9e481398 00000000 00000008 9f72ef54 9f1ee020 9f72ef40
ff00: 9e481398 9e481380 00000008 9f72ef40 9f1eff5c 9f1eff20 80039754 80038bfc
ff20: 00000000 9e481380 80894100 808e1662 00000000 9e4f2ec0 00000000 9e481380
ff40: 800396f8 00000000 00000000 00000000 9f1effac 9f1eff60 8003e020 80039704
ff60: ffffffff 00000000 ffffffff 9e481380 00000000 00000000 9f1eff78 9f1eff78
ff80: 00000000 00000000 9f1eff88 9f1eff88 9e4f2ec0 8003df30 00000000 00000000
ffa0: 00000000 9f1effb0 8000eb60 8003df3c 00000000 00000000 00000000 00000000
ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
ffe0: 00000000 00000000 00000000 00000000 00000013 00000000 ffffffff ffffffff
Backtrace:
[<803636ac>] (ftrace_raw_event_regmap_block) from [<80365f2c>] (_regmap_raw_read+0x1bc/0x1cc)
r9:00000001 r8:808e3840 r7:00000180 r6:00000000 r5:9eb2f490 r4:9f1fc800
[<80365d70>] (_regmap_raw_read) from [<80365f70>] (_regmap_bus_read+0x34/0x6c)
r10:00000000 r9:00000000 r8:9f732400 r7:9f1efe6c r6:9f1efe6c r5:9f1fc800
r4:9f1fc800
[<80365f3c>] (_regmap_bus_read) from [<803656a4>] (_regmap_read+0x7c/0x144)
r6:00000180 r5:9f1fc800 r4:9f1fc800 r3:80365f3c
[<80365628>] (_regmap_read) from [<803657bc>] (regmap_read+0x50/0x70)
r9:00000000 r8:9f732400 r7:9f1efe6c r6:9f1efe6c r5:00000180 r4:9f1fc800
[<8036576c>] (regmap_read) from [<80452ac0>] (imx_get_temp+0x134/0x1a4)
r6:9f1efeb4 r5:9f1fc800 r4:9e95f910 r3:00000001
[<8045298c>] (imx_get_temp) from [<8044e11c>] (thermal_zone_get_temp+0x58/0x74)
r7:9f72ef40 r6:9f1efeb4 r5:9e93d5e8 r4:9e93d400
[<8044e0c4>] (thermal_zone_get_temp) from [<8044fd14>] (thermal_zone_device_update+0x34/0xec)
r6:808e1978 r5:9e93d400 r4:9e93d608 r3:8045298c
[<8044fce0>] (thermal_zone_device_update) from [<8044fde8>] (thermal_zone_device_check+0x1c/0x20)
r5:9e481380 r4:9e93d608
[<8044fdcc>] (thermal_zone_device_check) from [<80038d50>] (process_one_work+0x160/0x3d4)
[<80038bf0>] (process_one_work) from [<80039754>] (worker_thread+0x5c/0x4f4)
r10:9f72ef40 r9:00000008 r8:9e481380 r7:9e481398 r6:9f72ef40 r5:9f1ee020
r4:9f72ef54
[<800396f8>] (worker_thread) from [<8003e020>] (kthread+0xf0/0x108)
r10:00000000 r9:00000000 r8:00000000 r7:800396f8 r6:9e481380 r5:00000000
r4:9e4f2ec0
[<8003df30>] (kthread) from [<8000eb60>] (ret_from_fork+0x14/0x34)
r7:00000000 r6:00000000 r5:8003df30 r4:9e4f2ec0
Code: e3140040 1a00001a e3140020 1a000016 (e596002c)
---[ end trace 193c15c2494ec960 ]---
Fixes: bdb0066df96e (mfd: syscon: Decouple syscon interface from platform devices)
Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/base/regmap/internal.h | 8 ++
drivers/base/regmap/regcache.c | 16 ++---
drivers/base/regmap/regmap.c | 32 ++++------
include/trace/events/regmap.h | 123 ++++++++++++++++++++---------------------
4 files changed, 91 insertions(+), 88 deletions(-)
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -237,4 +237,12 @@ extern struct regcache_ops regcache_rbtr
extern struct regcache_ops regcache_lzo_ops;
extern struct regcache_ops regcache_flat_ops;
+static inline const char *regmap_name(const struct regmap *map)
+{
+ if (map->dev)
+ return dev_name(map->dev);
+
+ return map->name;
+}
+
#endif
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -218,7 +218,7 @@ int regcache_read(struct regmap *map,
ret = map->cache_ops->read(map, reg, value);
if (ret == 0)
- trace_regmap_reg_read_cache(map->dev, reg, *value);
+ trace_regmap_reg_read_cache(map, reg, *value);
return ret;
}
@@ -311,7 +311,7 @@ int regcache_sync(struct regmap *map)
dev_dbg(map->dev, "Syncing %s cache\n",
map->cache_ops->name);
name = map->cache_ops->name;
- trace_regcache_sync(map->dev, name, "start");
+ trace_regcache_sync(map, name, "start");
if (!map->cache_dirty)
goto out;
@@ -346,7 +346,7 @@ out:
regmap_async_complete(map);
- trace_regcache_sync(map->dev, name, "stop");
+ trace_regcache_sync(map, name, "stop");
return ret;
}
@@ -381,7 +381,7 @@ int regcache_sync_region(struct regmap *
name = map->cache_ops->name;
dev_dbg(map->dev, "Syncing %s cache from %d-%d\n", name, min, max);
- trace_regcache_sync(map->dev, name, "start region");
+ trace_regcache_sync(map, name, "start region");
if (!map->cache_dirty)
goto out;
@@ -401,7 +401,7 @@ out:
regmap_async_complete(map);
- trace_regcache_sync(map->dev, name, "stop region");
+ trace_regcache_sync(map, name, "stop region");
return ret;
}
@@ -428,7 +428,7 @@ int regcache_drop_region(struct regmap *
map->lock(map->lock_arg);
- trace_regcache_drop_region(map->dev, min, max);
+ trace_regcache_drop_region(map, min, max);
ret = map->cache_ops->drop(map, min, max);
@@ -455,7 +455,7 @@ void regcache_cache_only(struct regmap *
map->lock(map->lock_arg);
WARN_ON(map->cache_bypass && enable);
map->cache_only = enable;
- trace_regmap_cache_only(map->dev, enable);
+ trace_regmap_cache_only(map, enable);
map->unlock(map->lock_arg);
}
EXPORT_SYMBOL_GPL(regcache_cache_only);
@@ -493,7 +493,7 @@ void regcache_cache_bypass(struct regmap
map->lock(map->lock_arg);
WARN_ON(map->cache_only && enable);
map->cache_bypass = enable;
- trace_regmap_cache_bypass(map->dev, enable);
+ trace_regmap_cache_bypass(map, enable);
map->unlock(map->lock_arg);
}
EXPORT_SYMBOL_GPL(regcache_cache_bypass);
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -1280,7 +1280,7 @@ int _regmap_raw_write(struct regmap *map
if (map->async && map->bus->async_write) {
struct regmap_async *async;
- trace_regmap_async_write_start(map->dev, reg, val_len);
+ trace_regmap_async_write_start(map, reg, val_len);
spin_lock_irqsave(&map->async_lock, flags);
async = list_first_entry_or_null(&map->async_free,
@@ -1338,8 +1338,7 @@ int _regmap_raw_write(struct regmap *map
return ret;
}
- trace_regmap_hw_write_start(map->dev, reg,
- val_len / map->format.val_bytes);
+ trace_regmap_hw_write_start(map, reg, val_len / map->format.val_bytes);
/* If we're doing a single register write we can probably just
* send the work_buf directly, otherwise try to do a gather
@@ -1371,8 +1370,7 @@ int _regmap_raw_write(struct regmap *map
kfree(buf);
}
- trace_regmap_hw_write_done(map->dev, reg,
- val_len / map->format.val_bytes);
+ trace_regmap_hw_write_done(map, reg, val_len / map->format.val_bytes);
return ret;
}
@@ -1406,12 +1404,12 @@ static int _regmap_bus_formatted_write(v
map->format.format_write(map, reg, val);
- trace_regmap_hw_write_start(map->dev, reg, 1);
+ trace_regmap_hw_write_start(map, reg, 1);
ret = map->bus->write(map->bus_context, map->work_buf,
map->format.buf_size);
- trace_regmap_hw_write_done(map->dev, reg, 1);
+ trace_regmap_hw_write_done(map, reg, 1);
return ret;
}
@@ -1469,7 +1467,7 @@ int _regmap_write(struct regmap *map, un
dev_info(map->dev, "%x <= %x\n", reg, val);
#endif
- trace_regmap_reg_write(map->dev, reg, val);
+ trace_regmap_reg_write(map, reg, val);
return map->reg_write(context, reg, val);
}
@@ -1772,7 +1770,7 @@ static int _regmap_raw_multi_reg_write(s
for (i = 0; i < num_regs; i++) {
int reg = regs[i].reg;
int val = regs[i].def;
- trace_regmap_hw_write_start(map->dev, reg, 1);
+ trace_regmap_hw_write_start(map, reg, 1);
map->format.format_reg(u8, reg, map->reg_shift);
u8 += reg_bytes + pad_bytes;
map->format.format_val(u8, val, 0);
@@ -1787,7 +1785,7 @@ static int _regmap_raw_multi_reg_write(s
for (i = 0; i < num_regs; i++) {
int reg = regs[i].reg;
- trace_regmap_hw_write_done(map->dev, reg, 1);
+ trace_regmap_hw_write_done(map, reg, 1);
}
return ret;
}
@@ -2058,15 +2056,13 @@ static int _regmap_raw_read(struct regma
*/
u8[0] |= map->read_flag_mask;
- trace_regmap_hw_read_start(map->dev, reg,
- val_len / map->format.val_bytes);
+ trace_regmap_hw_read_start(map, reg, val_len / map->format.val_bytes);
ret = map->bus->read(map->bus_context, map->work_buf,
map->format.reg_bytes + map->format.pad_bytes,
val, val_len);
- trace_regmap_hw_read_done(map->dev, reg,
- val_len / map->format.val_bytes);
+ trace_regmap_hw_read_done(map, reg, val_len / map->format.val_bytes);
return ret;
}
@@ -2122,7 +2118,7 @@ static int _regmap_read(struct regmap *m
dev_info(map->dev, "%x => %x\n", reg, *val);
#endif
- trace_regmap_reg_read(map->dev, reg, *val);
+ trace_regmap_reg_read(map, reg, *val);
if (!map->cache_bypass)
regcache_write(map, reg, *val);
@@ -2479,7 +2475,7 @@ void regmap_async_complete_cb(struct reg
struct regmap *map = async->map;
bool wake;
- trace_regmap_async_io_complete(map->dev);
+ trace_regmap_async_io_complete(map);
spin_lock(&map->async_lock);
list_move(&async->list, &map->async_free);
@@ -2524,7 +2520,7 @@ int regmap_async_complete(struct regmap
if (!map->bus || !map->bus->async_write)
return 0;
- trace_regmap_async_complete_start(map->dev);
+ trace_regmap_async_complete_start(map);
wait_event(map->async_waitq, regmap_async_is_done(map));
@@ -2533,7 +2529,7 @@ int regmap_async_complete(struct regmap
map->async_ret = 0;
spin_unlock_irqrestore(&map->async_lock, flags);
- trace_regmap_async_complete_done(map->dev);
+ trace_regmap_async_complete_done(map);
return ret;
}
--- a/include/trace/events/regmap.h
+++ b/include/trace/events/regmap.h
@@ -7,27 +7,26 @@
#include <linux/ktime.h>
#include <linux/tracepoint.h>
-struct device;
-struct regmap;
+#include "../../../drivers/base/regmap/internal.h"
/*
* Log register events
*/
DECLARE_EVENT_CLASS(regmap_reg,
- TP_PROTO(struct device *dev, unsigned int reg,
+ TP_PROTO(struct regmap *map, unsigned int reg,
unsigned int val),
- TP_ARGS(dev, reg, val),
+ TP_ARGS(map, reg, val),
TP_STRUCT__entry(
- __string( name, dev_name(dev) )
- __field( unsigned int, reg )
- __field( unsigned int, val )
+ __string( name, regmap_name(map) )
+ __field( unsigned int, reg )
+ __field( unsigned int, val )
),
TP_fast_assign(
- __assign_str(name, dev_name(dev));
+ __assign_str(name, regmap_name(map));
__entry->reg = reg;
__entry->val = val;
),
@@ -39,45 +38,45 @@ DECLARE_EVENT_CLASS(regmap_reg,
DEFINE_EVENT(regmap_reg, regmap_reg_write,
- TP_PROTO(struct device *dev, unsigned int reg,
+ TP_PROTO(struct regmap *map, unsigned int reg,
unsigned int val),
- TP_ARGS(dev, reg, val)
+ TP_ARGS(map, reg, val)
);
DEFINE_EVENT(regmap_reg, regmap_reg_read,
- TP_PROTO(struct device *dev, unsigned int reg,
+ TP_PROTO(struct regmap *map, unsigned int reg,
unsigned int val),
- TP_ARGS(dev, reg, val)
+ TP_ARGS(map, reg, val)
);
DEFINE_EVENT(regmap_reg, regmap_reg_read_cache,
- TP_PROTO(struct device *dev, unsigned int reg,
+ TP_PROTO(struct regmap *map, unsigned int reg,
unsigned int val),
- TP_ARGS(dev, reg, val)
+ TP_ARGS(map, reg, val)
);
DECLARE_EVENT_CLASS(regmap_block,
- TP_PROTO(struct device *dev, unsigned int reg, int count),
+ TP_PROTO(struct regmap *map, unsigned int reg, int count),
- TP_ARGS(dev, reg, count),
+ TP_ARGS(map, reg, count),
TP_STRUCT__entry(
- __string( name, dev_name(dev) )
- __field( unsigned int, reg )
- __field( int, count )
+ __string( name, regmap_name(map) )
+ __field( unsigned int, reg )
+ __field( int, count )
),
TP_fast_assign(
- __assign_str(name, dev_name(dev));
+ __assign_str(name, regmap_name(map));
__entry->reg = reg;
__entry->count = count;
),
@@ -89,48 +88,48 @@ DECLARE_EVENT_CLASS(regmap_block,
DEFINE_EVENT(regmap_block, regmap_hw_read_start,
- TP_PROTO(struct device *dev, unsigned int reg, int count),
+ TP_PROTO(struct regmap *map, unsigned int reg, int count),
- TP_ARGS(dev, reg, count)
+ TP_ARGS(map, reg, count)
);
DEFINE_EVENT(regmap_block, regmap_hw_read_done,
- TP_PROTO(struct device *dev, unsigned int reg, int count),
+ TP_PROTO(struct regmap *map, unsigned int reg, int count),
- TP_ARGS(dev, reg, count)
+ TP_ARGS(map, reg, count)
);
DEFINE_EVENT(regmap_block, regmap_hw_write_start,
- TP_PROTO(struct device *dev, unsigned int reg, int count),
+ TP_PROTO(struct regmap *map, unsigned int reg, int count),
- TP_ARGS(dev, reg, count)
+ TP_ARGS(map, reg, count)
);
DEFINE_EVENT(regmap_block, regmap_hw_write_done,
- TP_PROTO(struct device *dev, unsigned int reg, int count),
+ TP_PROTO(struct regmap *map, unsigned int reg, int count),
- TP_ARGS(dev, reg, count)
+ TP_ARGS(map, reg, count)
);
TRACE_EVENT(regcache_sync,
- TP_PROTO(struct device *dev, const char *type,
+ TP_PROTO(struct regmap *map, const char *type,
const char *status),
- TP_ARGS(dev, type, status),
+ TP_ARGS(map, type, status),
TP_STRUCT__entry(
- __string( name, dev_name(dev) )
- __string( status, status )
- __string( type, type )
- __field( int, type )
+ __string( name, regmap_name(map) )
+ __string( status, status )
+ __string( type, type )
+ __field( int, type )
),
TP_fast_assign(
- __assign_str(name, dev_name(dev));
+ __assign_str(name, regmap_name(map));
__assign_str(status, status);
__assign_str(type, type);
),
@@ -141,17 +140,17 @@ TRACE_EVENT(regcache_sync,
DECLARE_EVENT_CLASS(regmap_bool,
- TP_PROTO(struct device *dev, bool flag),
+ TP_PROTO(struct regmap *map, bool flag),
- TP_ARGS(dev, flag),
+ TP_ARGS(map, flag),
TP_STRUCT__entry(
- __string( name, dev_name(dev) )
- __field( int, flag )
+ __string( name, regmap_name(map) )
+ __field( int, flag )
),
TP_fast_assign(
- __assign_str(name, dev_name(dev));
+ __assign_str(name, regmap_name(map));
__entry->flag = flag;
),
@@ -161,32 +160,32 @@ DECLARE_EVENT_CLASS(regmap_bool,
DEFINE_EVENT(regmap_bool, regmap_cache_only,
- TP_PROTO(struct device *dev, bool flag),
+ TP_PROTO(struct regmap *map, bool flag),
- TP_ARGS(dev, flag)
+ TP_ARGS(map, flag)
);
DEFINE_EVENT(regmap_bool, regmap_cache_bypass,
- TP_PROTO(struct device *dev, bool flag),
+ TP_PROTO(struct regmap *map, bool flag),
- TP_ARGS(dev, flag)
+ TP_ARGS(map, flag)
);
DECLARE_EVENT_CLASS(regmap_async,
- TP_PROTO(struct device *dev),
+ TP_PROTO(struct regmap *map),
- TP_ARGS(dev),
+ TP_ARGS(map),
TP_STRUCT__entry(
- __string( name, dev_name(dev) )
+ __string( name, regmap_name(map) )
),
TP_fast_assign(
- __assign_str(name, dev_name(dev));
+ __assign_str(name, regmap_name(map));
),
TP_printk("%s", __get_str(name))
@@ -194,50 +193,50 @@ DECLARE_EVENT_CLASS(regmap_async,
DEFINE_EVENT(regmap_block, regmap_async_write_start,
- TP_PROTO(struct device *dev, unsigned int reg, int count),
+ TP_PROTO(struct regmap *map, unsigned int reg, int count),
- TP_ARGS(dev, reg, count)
+ TP_ARGS(map, reg, count)
);
DEFINE_EVENT(regmap_async, regmap_async_io_complete,
- TP_PROTO(struct device *dev),
+ TP_PROTO(struct regmap *map),
- TP_ARGS(dev)
+ TP_ARGS(map)
);
DEFINE_EVENT(regmap_async, regmap_async_complete_start,
- TP_PROTO(struct device *dev),
+ TP_PROTO(struct regmap *map),
- TP_ARGS(dev)
+ TP_ARGS(map)
);
DEFINE_EVENT(regmap_async, regmap_async_complete_done,
- TP_PROTO(struct device *dev),
+ TP_PROTO(struct regmap *map),
- TP_ARGS(dev)
+ TP_ARGS(map)
);
TRACE_EVENT(regcache_drop_region,
- TP_PROTO(struct device *dev, unsigned int from,
+ TP_PROTO(struct regmap *map, unsigned int from,
unsigned int to),
- TP_ARGS(dev, from, to),
+ TP_ARGS(map, from, to),
TP_STRUCT__entry(
- __string( name, dev_name(dev) )
- __field( unsigned int, from )
- __field( unsigned int, to )
+ __string( name, regmap_name(map) )
+ __field( unsigned int, from )
+ __field( unsigned int, to )
),
TP_fast_assign(
- __assign_str(name, dev_name(dev));
+ __assign_str(name, regmap_name(map));
__entry->from = from;
__entry->to = to;
),
Patches currently in stable-queue which might be from p.zabel@xxxxxxxxxxxxxx are
queue-3.19/regmap-introduce-regmap_name-to-fix-syscon-regmap-trace-events.patch
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