On 08.06.21 11:20, Dongjiu Geng wrote: > Hi, > From the jailhouse design, the Private Per-CPU data should be not > accessed by other CPUs except the current CPU. But from the code[1] > and my test, it is not. For example, the CPU1 can access the CPU0's > private data, because hv_paging_structs already map it, and the > per-cpu page table will link the hv_paging_structs. is this a bug？ I > think the Private Per-CPU data should be not accessed by other CPUs > except the self CPU. > > [1]: err = paging_create(&hv_paging_structs, > paging_hvirt2phys(&hypervisor_header), > system_config->hypervisor_memory.size, > (unsigned long)&hypervisor_header, > PAGE_DEFAULT_FLAGS, > PAGING_NON_COHERENT | PAGING_HUGE); >
You are referring to https://github.com/siemens/jailhouse/blob/6d9c51d0bd819689c00f6a3c38d3099f6eb9c657/hypervisor/paging.c#L678: Right, the initial mapping means everything is visible for all CPUs. But then comes https://github.com/siemens/jailhouse/blob/6d9c51d0bd819689c00f6a3c38d3099f6eb9c657/hypervisor/setup.c#L100 which setups up an alternative mapping (installed by arch_cpu_init()). That does not contain the private data structs of the other CPUs. You should be able to confirm that AFTER initialization, e.g. on a first VM exit after setup. Jan -- Siemens AG, T RDA IOT Corporate Competence Center Embedded Linux -- You received this message because you are subscribed to the Google Groups "Jailhouse" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/jailhouse-dev/f220116c-a666-5b73-9fe3-e5e4acd1583d%40siemens.com.
