On Fri, Jul 21, 2023 at 05:55:33PM +0300, Dan Carpenter wrote:
> The kunit tests discovered a sleeping in atomic bug. The allocations
> in the regcache-rbtree code should use the map->alloc_flags instead of
> GFP_KERNEL.
>
> [ 5.005510] BUG: sleeping function called from invalid context at include/linux/sched/mm.h:306
> [ 5.005960] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 117, name: kunit_try_catch
> [ 5.006219] preempt_count: 1, expected: 0
> [ 5.006414] 1 lock held by kunit_try_catch/117:
> [ 5.006590] #0: 833b9010 (regmap_kunit:86:(config)->lock){....}-{2:2}, at: regmap_lock_spinlock+0x14/0x1c
> [ 5.007493] irq event stamp: 162
> [ 5.007627] hardirqs last enabled at (161): [<80786738>] crng_make_state+0x1a0/0x294
> [ 5.007871] hardirqs last disabled at (162): [<80c531ec>] _raw_spin_lock_irqsave+0x7c/0x80
> [ 5.008119] softirqs last enabled at (0): [<801110ac>] copy_process+0x810/0x2138
> [ 5.008356] softirqs last disabled at (0): [<00000000>] 0x0
> [ 5.008688] CPU: 0 PID: 117 Comm: kunit_try_catch Tainted: G N 6.4.4-rc3-g0e8d2fdfb188 #1
> [ 5.009011] Hardware name: Generic DT based system
> [ 5.009277] unwind_backtrace from show_stack+0x18/0x1c
> [ 5.009497] show_stack from dump_stack_lvl+0x38/0x5c
> [ 5.009676] dump_stack_lvl from __might_resched+0x188/0x2d0
> [ 5.009860] __might_resched from __kmem_cache_alloc_node+0x1dc/0x25c
> [ 5.010061] __kmem_cache_alloc_node from kmalloc_trace+0x30/0xc8
> [ 5.010254] kmalloc_trace from regcache_rbtree_write+0x26c/0x468
> [ 5.010446] regcache_rbtree_write from _regmap_write+0x88/0x140
> [ 5.010634] _regmap_write from regmap_write+0x44/0x68
> [ 5.010803] regmap_write from basic_read_write+0x8c/0x270
> [ 5.010980] basic_read_write from kunit_try_run_case+0x48/0xa0
>
> Fixes: 28644c809f44 ("regmap: Add the rbtree cache support")
> Reported-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> Closes: https://lore.kernel.org/all/ee59d128-413c-48ad-a3aa-d9d350c80042@xxxxxxxxxxxx/
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Tested-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> ---
> This patch is similar to what I sent earlier, but I changed
> regcache_rbtree_init() back to using GFP_KERNEL.
>
> drivers/base/regmap/regcache-rbtree.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/base/regmap/regcache-rbtree.c b/drivers/base/regmap/regcache-rbtree.c
> index fabf87058d80..ae6b8788d5f3 100644
> --- a/drivers/base/regmap/regcache-rbtree.c
> +++ b/drivers/base/regmap/regcache-rbtree.c
> @@ -277,7 +277,7 @@ static int regcache_rbtree_insert_to_block(struct regmap *map,
>
> blk = krealloc(rbnode->block,
> blklen * map->cache_word_size,
> - GFP_KERNEL);
> + map->alloc_flags);
> if (!blk)
> return -ENOMEM;
>
> @@ -286,7 +286,7 @@ static int regcache_rbtree_insert_to_block(struct regmap *map,
> if (BITS_TO_LONGS(blklen) > BITS_TO_LONGS(rbnode->blklen)) {
> present = krealloc(rbnode->cache_present,
> BITS_TO_LONGS(blklen) * sizeof(*present),
> - GFP_KERNEL);
> + map->alloc_flags);
> if (!present)
> return -ENOMEM;
>
> @@ -320,7 +320,7 @@ regcache_rbtree_node_alloc(struct regmap *map, unsigned int reg)
> const struct regmap_range *range;
> int i;
>
> - rbnode = kzalloc(sizeof(*rbnode), GFP_KERNEL);
> + rbnode = kzalloc(sizeof(*rbnode), map->alloc_flags);
> if (!rbnode)
> return NULL;
>
> @@ -346,13 +346,13 @@ regcache_rbtree_node_alloc(struct regmap *map, unsigned int reg)
> }
>
> rbnode->block = kmalloc_array(rbnode->blklen, map->cache_word_size,
> - GFP_KERNEL);
> + map->alloc_flags);
> if (!rbnode->block)
> goto err_free;
>
> rbnode->cache_present = kcalloc(BITS_TO_LONGS(rbnode->blklen),
> sizeof(*rbnode->cache_present),
> - GFP_KERNEL);
> + map->alloc_flags);
> if (!rbnode->cache_present)
> goto err_free_block;
>
> --
> 2.39.2
>
