On 2024/7/16 14:14, Zhaoyang Huang wrote:
On Tue, Jul 16, 2024 at 1:50 PM Gao Xiang <hsiang...@linux.alibaba.com> wrote:
On 2024/7/16 13:44, zhaoyang.huang wrote:
From: Zhaoyang Huang <zhaoyang.hu...@unisoc.com>
scheduling while atomic was reported as below where the schedule_timeout
comes from too_many_isolated when doing direct_reclaim. Fix this by
masking GFP_DIRECT_RECLAIM from gfp.
[ 175.610416][ T618] BUG: scheduling while atomic:
kworker/u16:6/618/0x00000000
[ 175.643480][ T618] CPU: 2 PID: 618 Comm: kworker/u16:6 Tainted: G
[ 175.645791][ T618] Workqueue: loop20 loop_workfn
[ 175.646394][ T618] Call trace:
[ 175.646785][ T618] dump_backtrace+0xf4/0x140
[ 175.647345][ T618] show_stack+0x20/0x2c
[ 175.647846][ T618] dump_stack_lvl+0x60/0x84
[ 175.648394][ T618] dump_stack+0x18/0x24
[ 175.648895][ T618] __schedule_bug+0x64/0x90
[ 175.649445][ T618] __schedule+0x680/0x9b8
[ 175.649970][ T618] schedule+0x130/0x1b0
[ 175.650470][ T618] schedule_timeout+0xac/0x1d0
[ 175.651050][ T618] schedule_timeout_uninterruptible+0x24/0x34
[ 175.651789][ T618] __alloc_pages_slowpath+0x8dc/0x121c
[ 175.652455][ T618] __alloc_pages+0x294/0x2fc
[ 175.653011][ T618] erofs_allocpage+0x48/0x58
[ 175.653572][ T618] z_erofs_runqueue+0x314/0x8a4
[ 175.654161][ T618] z_erofs_readahead+0x258/0x318
[ 175.654761][ T618] read_pages+0x88/0x394
[ 175.655275][ T618] page_cache_ra_unbounded+0x1cc/0x23c
[ 175.655939][ T618] page_cache_ra_order+0x27c/0x33c
[ 175.656559][ T618] ondemand_readahead+0x224/0x334
[ 175.657169][ T618] page_cache_async_ra+0x60/0x9c
[ 175.657767][ T618] filemap_get_pages+0x19c/0x7cc
[ 175.658367][ T618] filemap_read+0xf0/0x484
[ 175.658901][ T618] generic_file_read_iter+0x4c/0x15c
[ 175.659543][ T618] do_iter_read+0x224/0x348
[ 175.660100][ T618] vfs_iter_read+0x24/0x38
[ 175.660635][ T618] loop_process_work+0x408/0xa68
[ 175.661236][ T618] loop_workfn+0x28/0x34
[ 175.661751][ T618] process_scheduled_works+0x254/0x4e8
[ 175.662417][ T618] worker_thread+0x24c/0x33c
[ 175.662974][ T618] kthread+0x110/0x1b8
[ 175.663465][ T618] ret_from_fork+0x10/0x20
Signed-off-by: Zhaoyang Huang <zhaoyang.hu...@unisoc.com>
I don't see why it's an atomic context,
so this patch is incorrect.
Sorry, I should provide more details. page_cache_ra_unbounded() will
call filemap_invalidate_lock_shared(mapping) to ensure the integrity
of page cache during readahead, which will disable preempt.
Why a rwsem sleepable lock disable preemption? .readahead
context should be always non-atomic context, which is applied
to all kernel filesystems.
Thanks,
Gao Xiang
Thanks,
Gao Xiang
