On 11.03.2025 21:59, Julien Grall wrote: > On 05/03/2025 09:11, Mykola Kvach wrote: >> Invocation of the CPU_UP_PREPARE notification >> on ARM64 during resume causes a crash: >> >> (XEN) [ 315.807606] Error bringing CPU1 up: -16 >> (XEN) [ 315.811926] Xen BUG at common/cpu.c:258 >> [...] >> (XEN) [ 316.142765] Xen call trace: >> (XEN) [ 316.146048] [<00000a0000202264>] enable_nonboot_cpus+0x128/0x1ac >> (PC) >> (XEN) [ 316.153219] [<00000a000020225c>] enable_nonboot_cpus+0x120/0x1ac >> (LR) >> (XEN) [ 316.160391] [<00000a0000278180>] >> suspend.c#system_suspend+0x4c/0x1a0 >> (XEN) [ 316.167476] [<00000a0000206b70>] >> domain.c#continue_hypercall_tasklet_handler+0x54/0xd0 >> (XEN) [ 316.176117] [<00000a0000226538>] >> tasklet.c#do_tasklet_work+0xb8/0x100 >> (XEN) [ 316.183288] [<00000a0000226920>] do_tasklet+0x68/0xb0 >> (XEN) [ 316.189077] [<00000a000026e120>] domain.c#idle_loop+0x7c/0x194 >> (XEN) [ 316.195644] [<00000a0000277638>] shutdown.c#halt_this_cpu+0/0x14 >> (XEN) [ 316.202383] [<0000000000000008>] 0000000000000008 >> >> Freeing per-CPU areas and setting __per_cpu_offset to INVALID_PERCPU_AREA >> only occur when !park_offline_cpus and system_state is not SYS_STATE_suspend. >> On ARM64, park_offline_cpus is always false, so setting __per_cpu_offset to >> INVALID_PERCPU_AREA depends solely on the system state. >> >> If the system is suspended, this area is not freed, and during resume, an >> error >> occurs in init_percpu_area, causing a crash because INVALID_PERCPU_AREA is >> not >> set and park_offline_cpus remains 0: >> >> if ( __per_cpu_offset[cpu] != INVALID_PERCPU_AREA ) >> return park_offline_cpus ? 0 : -EBUSY; >> >> It appears that the same crash can occur on x86 if park_offline_cpus is set >> to 0 during Xen suspend. > > I am rather confused. Looking at the x86 code, it seems > park_offline_cpus is cleared for AMD platforms. So are you saying the > suspend/resume doesn't work on AMD?
Right now I can't see how it would work there. I've asked Marek for clarification as to their users using S3 only on Intel hardware. Jan
