On Tue, Oct 08, 2024 at 02:26:17PM +0900, Sergey Senozhatsky wrote: > Didn't copy one more backtrace here, there are two mutexes involved. > > schedule+0x554/0x1218 > schedule_preempt_disabled+0x30/0x50 > mutex_lock+0x3c/0x70 > sr_block_release+0x2c/0x60 [sr_mod (HASH:d5f2 4)] > blkdev_put+0x184/0x290 > blkdev_release+0x34/0x50 > __fput_sync+0xa8/0x2d8 > __arm64_sys_close+0x6c/0xd8 > invoke_syscall+0x78/0xf0 > > So process A holds cd->lock and sleeps in blk_queue_enter() > process B holds ->open_mutex and sleeps on cd->lock, which is owned by A > process C sleeps on ->open_mutex, which is owned by B. Oh, cd->mutex is a bit of a problem. And looking into the generic CD layer code this can be relatively easily avoided while cleaning a lot of the code up. Give me a little time to cook something up. I also wonder if simulating a cdrom removal might be possible using qemu to help reproducing some of this.
