-----Original Message----- > 在 2021年04月16日 17:25, Johan.Erlandsson@xxxxxxxx 写道: > > Hi Lianbo > > > >>> > >>> With enough continuous physical memory we can have 1GB block. This have > >>> been seen only in linear mapping region in kernel space. I have only > >>> verified this for VM_L3_4K. > >>> > >>> reference: alloc_init_pud(), use_1G_block() [arch/arm64/mm/mmu.c] > >>> > >> For this situation, do you know how to reproduce it easily? Can you share > >> your steps in detail? > > > > I can try, one requirement is that you have memory aligned at 1 GB and > > size is at least 1 GB. Lets assume we have vmcore with physical memory > > at 0x100000000 (1 GB aligned) with size at least 1 GB. Then from crash we > > could do: > > > Thank you for the explanation, Johan. > > I will try to reproduce it later, but anyway, this patch and test are good to me. > > Acked-by: Lianbo Jiang <lijiang@xxxxxxxxxx> Thanks, applied: https://github.com/crash-utility/crash/commit/dccdf95c25234e3573a7a0744430e922146ee362 Kazu > > > crash> ptov 100000000 > > VIRTUAL PHYSICAL > > ffffffe900000000 100000000 > > > > crash> vtop ffffffe900000000 > > VIRTUAL PHYSICAL > > ffffffe900000000 100000000 > > > > PAGE DIRECTORY: ffffff990f66c000 > > PGD: ffffff990f66cd20 => 68000100000711 > > PAGE: 100000000 (1GB) > > > > PTE PHYSICAL FLAGS > > 68000100000711 100000000 (VALID|SHARED|AF|PXN|UXN) > > > > PAGE PHYSICAL MAPPING INDEX CNT FLAGS > > ffffffbfa4000000 100000000 ffffffe97de59090 fe 2 20054 > uptodate,lru,workingset,mappedtodisk > > > > I hope that helps. > > Yes, it certainly helps. > > Thanks > Lianbo > > > Regards > > Johan > > > >> BTW: I did the test, but I didn't enter into the kernel code path because > >> that condition was not met. > >> > >> # dmesg|grep -i huge > >> [ 0.000000] Kernel command line: BOOT_IMAGE=(hd0,gpt2)/vmlinuz-5.12.0-rc7+ > root=/dev/mapper/rhel_gigabyte--r120--20-root ro arm->smmu.disable_bypass=n > initcall_blacklist=gtdt_sbsa_gwdt_init iommu.passthrough=1 crashkernel=512M hugepagesz=1G hugepages=6 > >debug_pagealloc=on rd.lvm.lv=rhel_gigabyte-r120-20/root rd.lvm.lv=rhel_gigabyte-r120-20/swap > >> [ 2.620634] HugeTLB registered 1.00 GiB page size, pre-allocated 6 pages > >> > >> Thanks. > >> Lianbo > > > > > > -- Crash-utility mailing list Crash-utility@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/crash-utility
