On 01/04/20 7:30 PM, Pingfan Liu wrote: > 'mem=" option is an easy way to put high pressure on memory during some > test. Hence after applying the memory limit, instead of total mem, the > actual usable memory should be considered when reserving mem for > crashkernel. Otherwise the boot up may experience OOM issue. > > E.g. it would reserve 4G prior to the change and 512M afterward, if passing > crashkernel="2G-4G:384M,4G-16G:512M,16G-64G:1G,64G-128G:2G,128G-:4G", and > mem=5G on a 256G machine. > > This issue is powerpc specific because it puts higher priority on fadump > and kdump reservation than on "mem=". Referring the following code: > if (fadump_reserve_mem() == 0) > reserve_crashkernel(); > ... > /* Ensure that total memory size is page-aligned. */ > limit = ALIGN(memory_limit ?: memblock_phys_mem_size(), PAGE_SIZE); > memblock_enforce_memory_limit(limit); > > While on other arches, the effect of "mem=" takes a higher priority and pass > through memblock_phys_mem_size() before calling reserve_crashkernel(). >> Signed-off-by: Pingfan Liu <kernelfans@xxxxxxxxx> > To: linuxppc-dev@xxxxxxxxxxxxxxxx > Cc: Hari Bathini <hbathini@xxxxxxxxxxxxx> > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > Cc: kexec@xxxxxxxxxxxxxxxxxxx > --- > v3 -> v4: fix total_mem_sz based on adjusted memory_limit Thanks for the update. Reviewed-by: Hari Bathini <hbathini@xxxxxxxxxxxxx> _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
