mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-06 02:50:49 +09:00
fe646761cb
commit 61cce6f6ee upstream.
When boxes are run near (or to) OOM, we have a problem with the discard
page allocation in sd. If we fail allocating the special page, we return
busy, and it'll get retried. But since ordering is honored for dispatch
requests, we can keep retrying this same IO and failing. Behind that IO
could be requests that want to free memory, but they never get the
chance. This means you get repeated spews of traces like this:
[1201401.625972] Call Trace:
[1201401.631748] dump_stack+0x4d/0x65
[1201401.639445] warn_alloc+0xec/0x190
[1201401.647335] __alloc_pages_slowpath+0xe84/0xf30
[1201401.657722] ? get_page_from_freelist+0x11b/0xb10
[1201401.668475] ? __alloc_pages_slowpath+0x2e/0xf30
[1201401.679054] __alloc_pages_nodemask+0x1f9/0x210
[1201401.689424] alloc_pages_current+0x8c/0x110
[1201401.699025] sd_setup_write_same16_cmnd+0x51/0x150
[1201401.709987] sd_init_command+0x49c/0xb70
[1201401.719029] scsi_setup_cmnd+0x9c/0x160
[1201401.727877] scsi_queue_rq+0x4d9/0x610
[1201401.736535] blk_mq_dispatch_rq_list+0x19a/0x360
[1201401.747113] blk_mq_sched_dispatch_requests+0xff/0x190
[1201401.758844] __blk_mq_run_hw_queue+0x95/0xa0
[1201401.768653] blk_mq_run_work_fn+0x2c/0x30
[1201401.777886] process_one_work+0x14b/0x400
[1201401.787119] worker_thread+0x4b/0x470
[1201401.795586] kthread+0x110/0x150
[1201401.803089] ? rescuer_thread+0x320/0x320
[1201401.812322] ? kthread_park+0x90/0x90
[1201401.820787] ? do_syscall_64+0x53/0x150
[1201401.829635] ret_from_fork+0x29/0x40
Ensure that the discard page allocation has a mempool backing, so we
know we can make progress.
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.