On 4/11/22 07:20, zhangfei....@foxmail.com wrote: >> Is there nothing before this call trace? Usually there will be at least >> some warning text. > I added dump_stack() in ioasid_free.
Hold on a sec, though... What's the *problem* here? Did something break or are you just saying that something looks weird to _you_? For instance, if we have: nginx: ioasid_alloc()==1 fork(); // spawn the daemon exit(); ioasid_free(1); and then a moment later: lynx: ioasid_alloc()==1 fork(); exit(); ioasid_free(1); There's no problem. The original nginx process with ioasid==1 exited. The fact that *some* process called nginx is still running doesn't mean that it still has a reference to asid==1. Are you sure the nginx process that allocated the ASID is the same process you see in ps? _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu