Messages in this thread |  | | Date | Mon, 11 Apr 2022 07:36:26 -0700 | From | Dave Hansen <> | Subject | Re: [PATCH v4 05/11] iommu/sva: Assign a PASID to mm on PASID allocation and free it on mm exit |
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On 4/11/22 07:20, zhangfei.gao@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?
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