On 2014-06-19 08:35, Theodore Ts'o wrote:
While trying to bisect some problems which were introduced sometime between 3.15 and 3.16-rc1 (specifically, (1) reads to a block device at offset 262144 * 4k are failing with a short read, and (2) block device reads are sometimes causing the entire kernel to hang), the following BUG got hit. [ 0.000000] Linux version 3.15.0-rc8-06047-gaaeb255 (tytso@closure) (gcc version 4.8.3 (Debian 4.8.3-2) ) #1902 SMP Thu Jun 19 11:16:10 EDT 2014 [....] Checking file systems...fsck from util-linux 2.20.1 /dev/vdg was not cleanly unmounted, check forced. [ 4.161703] BUG: scheduling while atomic: fsck.ext4/2072/0x0000000266.5% [ 4.163673] no locks held by fsck.ext4/2072. [ 4.164318] Modules linked in: [ 4.164845] CPU: 0 PID: 2072 Comm: fsck.ext4 Not tainted 3.15.0-rc8-06047-gaaeb255 #1902 [ 4.166047] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 4.166917] 00000000 00000000 f52c5ba0 c0832655 f5158610 f52c5bac c082f88a f6501e40 [ 4.168188] f52c5c20 c08362ca c0eb3e40 c0eb3e40 374d3933 00000001 0396a8da 00000000 [ 4.169474] f5158610 f51f1674 f4f46a00 f52c5be4 c015dd4b f4f46a00 f52c5bf0 c015dd5e [ 4.170781] Call Trace: [ 4.171159] [<c0832655>] dump_stack+0x48/0x60 [ 4.171838] [<c082f88a>] __schedule_bug+0x5c/0x6d [ 4.172572] [<c08362ca>] __schedule+0x61/0x65a [ 4.173228] [<c015dd4b>] ? kvm_clock_read+0x1f/0x29 [ 4.173977] [<c015dd5e>] ? kvm_clock_get_cycles+0x9/0xc [ 4.174771] [<c01b4cb9>] ? timekeeping_get_ns.constprop.14+0x10/0x56 [ 4.175701] [<c0836922>] schedule+0x5f/0x61 [ 4.176345] [<c0836aa2>] io_schedule+0x50/0x67 [ 4.177060] [<c0423b2d>] bt_get+0xaf/0xd1 [ 4.177677] [<c0198282>] ? wake_up_atomic_t+0x1f/0x1f [ 4.178444] [<c0423bfd>] blk_mq_get_tag+0x26/0x82 [ 4.179158] [<c0420f14>] __blk_mq_alloc_request+0x2a/0x169 [ 4.180022] [<c04222b5>] blk_mq_map_request+0x137/0x1e3 [ 4.180825] [<c0422f89>] blk_sq_make_request+0x82/0x145 [ 4.181630] [<c041a687>] generic_make_request+0x82/0xb5 [ 4.182430] [<c041a7aa>] submit_bio+0xf0/0x109 [ 4.183113] [<c019e97c>] ? trace_hardirqs_on_caller+0x14e/0x169 [ 4.184019] [<c025de72>] _submit_bh+0x1ad/0x1ca [ 4.184661] [<c025de9e>] submit_bh+0xf/0x11 [ 4.185267] [<c025f5c9>] block_read_full_page+0x1e2/0x1f2 [ 4.186073] [<c025f8cd>] ? I_BDEV+0xa/0xa [ 4.186695] [<c020ad30>] ? __lru_cache_add+0x24/0x46 [ 4.187452] [<c020af13>] ? lru_cache_add+0xd/0xf [ 4.188130] [<c025fc04>] blkdev_readpage+0x14/0x16 [ 4.188832] [<c0209adf>] __do_page_cache_readahead+0x1c0/0x1eb [ 4.189704] [<c0209cb9>] ondemand_readahead+0x1af/0x1b9 [ 4.190508] [<c0209d22>] page_cache_async_readahead+0x5f/0x6a [ 4.191424] [<c0202370>] generic_file_aio_read+0x226/0x4f4 [ 4.192272] [<c0260841>] blkdev_aio_read+0x90/0x9e [ 4.193017] [<c02385cd>] do_sync_read+0x52/0x79 [ 4.193731] [<c023857b>] ? fdput_pos+0x25/0x25 [ 4.194412] [<c0238d27>] vfs_read+0x72/0xd1 [ 4.195064] [<c02391da>] SyS_read+0x49/0x7c [ 4.195700] [<c083a0c9>] syscall_call+0x7/0xb [ 4.196385] [<c0830000>] ? print_usage_bug+0xcd/0x18e Is any of these known problems? This is blocking me from doing any kind of testing at the moment... (these problems are showing up while running KVM using virtio devices).
I believe you already reported this issue a while back, and it should be fixed by commit cb96a42c in the kernel.
The other issue, not sure, not a lot of detail. It may be fixed by the pull request I sent out yesterday. You can try pulling in:
git://git.kernel.dk/linux-block.git for-linus and see if that fixes it for you. -- Jens Axboe -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
