HI,
after applying your patch[1], the system will panic after reboot.
OK ] Finished Coldplug All udev Devices.
[ OK ] Reached target Network.
Starting dracut initqueue hook...
[ 4.675720] list_add double add: new=ffff90b056320a48,
prev=ffffa4f685f43a70, next=ffff90b056320a48.
[ 4.684931] ------------[ cut here ]------------
[ 4.689578] kernel BUG at lib/list_debug.c:33!
[ 4.694053] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[ 4.699134] CPU: 14 PID: 706 Comm: systemd-udevd Not tainted 6.4.0-rc1+ #2
[ 4.706049] Hardware name: HPE ProLiant DL380 Gen10/ProLiant DL380
Gen10, BIOS U30 06/20/2018
[ 4.714621] RIP: 0010:__list_add_valid+0x8b/0x90
[ 4.719271] Code: d1 4c 89 c6 4c 89 ca 48 c7 c7 78 d1 bb 99 e8 cc
56 b6 ff 0f 0b 48 89 f2 4c 89 c1 48 89 fe 48 c7 c7 d0 d1 bb 99 e8 b5
56 b6 ff <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
90 48
[ 4.738150] RSP: 0018:ffffa4f685f43a48 EFLAGS: 00010246
[ 4.743405] RAX: 0000000000000058 RBX: ffff90b056320a00 RCX: 0000000000000000
[ 4.750578] RDX: 0000000000000000 RSI: ffff90b76fb9f840 RDI: ffff90b76fb9f840
[ 4.757752] RBP: ffffa4f685f43a68 R08: 0000000000000000 R09: 00000000ffff7fff
[ 4.764925] R10: ffffa4f685f43900 R11: ffffffff9a1e6888 R12: ffffa4f685f43b78
[ 4.772100] R13: ffffa4f685f43a70 R14: ffff90b38a035800 R15: ffff90b056320a48
[ 4.779275] FS: 00007fea88741540(0000) GS:ffff90b76fb80000(0000)
knlGS:0000000000000000
[ 4.787411] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 4.793189] CR2: 00007fff014ba608 CR3: 0000000449ed4006 CR4: 00000000007706e0
[ 4.800362] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 4.807536] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 4.814710] PKRU: 55555554
[ 4.817429] Call Trace:
[ 4.819887] <TASK>
[ 4.821995] blk_mq_dispatch_plug_list+0x112/0x320
[ 4.826820] blk_mq_flush_plug_list+0x43/0x190
[ 4.831289] __blk_flush_plug+0x102/0x160
[ 4.835325] blk_finish_plug+0x25/0x40
[ 4.839095] read_pages+0x19a/0x220
[ 4.842606] page_cache_ra_unbounded+0x137/0x180
[ 4.847250] force_page_cache_ra+0xc5/0xf0
[ 4.851369] filemap_get_pages+0xf9/0x360
[ 4.855406] filemap_read+0xc5/0x320
[ 4.859001] ? generic_fillattr+0x45/0xf0
[ 4.863036] ? _copy_to_user+0x20/0x40
[ 4.866808] ? cp_new_stat+0x150/0x180
[ 4.870579] blkdev_read_iter+0xaf/0x170
[ 4.874524] vfs_read+0x1b5/0x2d0
[ 4.877860] ksys_read+0x5f/0xe0
[ 4.881107] do_syscall_64+0x59/0x90
[ 4.884706] ? exc_page_fault+0x65/0x150
[ 4.888653] entry_SYSCALL_64_after_hwframe+0x72/0xdc
[ 4.893737] RIP: 0033:0x7fea8934eaf2
[1] https://lore.kernel.org/linux-block/007af59f-4f4c-f779-a1b6-aaa81ff640b3@xxxxxxxxxxxxxxx/
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index f6dad0886a2f..bd94d8a5416f 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -2712,6 +2712,7 @@ static void blk_mq_dispatch_plug_list(struct
> blk_plug *plug, bool from_sched)
> struct request **requeue_lastp = &requeue_list;
> unsigned int depth = 0;
> LIST_HEAD(list);
> + LIST_HEAD(passthrough_list);
>
> do {
> struct request *rq = rq_list_pop(&plug->mq_list);
> @@ -2723,7 +2724,10 @@ static void blk_mq_dispatch_plug_list(struct
> blk_plug *plug, bool from_sched)
> rq_list_add_tail(&requeue_lastp, rq);
> continue;
> }
> - list_add(&rq->queuelist, &list);
> + if (blk_rq_is_passthrough(rq))
> + list_add(&rq->queuelist, &passthrough_list);
> + else
> + list_add(&rq->queuelist, &list);
> depth++;
> } while (!rq_list_empty(plug->mq_list));
>
> @@ -2731,6 +2735,9 @@ static void blk_mq_dispatch_plug_list(struct
> blk_plug *plug, bool from_sched)
> trace_block_unplug(this_hctx->queue, depth, !from_sched);
>
> percpu_ref_get(&this_hctx->queue->q_usage_counter);
> + if (!list_empty(&passthrough_list))
> + blk_mq_insert_requests(this_hctx, this_ctx,
> &passthrough_list,
> + from_sched);
> if (this_hctx->queue->elevator) {
>
> this_hctx->queue->elevator->type->ops.insert_requests(this_hctx,
> &list, 0);
>
> Thanks,
> Kuai
>
--
Guangwu Zhang, RHCE, ISTQB, ITIL
Quality Engineer, Kernel Storage QE
Red Hat
