On 2022/5/7 7:10, Baoquan He wrote: > On 05/06/22 at 07:43pm, Zhen Lei wrote: > ...... >> @@ -118,8 +162,7 @@ static void __init reserve_crashkernel(void) >> if (crash_base) >> crash_max = crash_base + crash_size; >> >> - /* Current arm64 boot protocol requires 2MB alignment */ >> - crash_base = memblock_phys_alloc_range(crash_size, SZ_2M, >> + crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN, >> crash_base, crash_max); >> if (!crash_base) { >> pr_warn("cannot allocate crashkernel (size:0x%llx)\n", >> @@ -127,6 +170,11 @@ static void __init reserve_crashkernel(void) >> return; >> } >> > > There's corner case missed, e.g > 1) ,high and ,low are specified, CONFIG_ZONE_DMA|DMA32 is not enabled; > 2) ,high and ,low are specified, the whole system memory is under 4G. > > Below judgement can filter them away: > > if (crash_base > arm64_dma_phys_limit && crash_low_size && > reserve_crashkernel_low(crash_low_size)) { > > What's your opinion? Leave it and add document to notice user, or fix it > with code change? I think maybe we can leave it unchanged. If the user configures two memory ranges, we'd better apply for two. Otherwise, he'll be confused when he inquires. Currently, crash_low_size is non-zero only when 'crashkernel=Y,low' is explicitly configured. > > I would suggest merging this series, Lei can add this corner case > handling on top. Since this is a newly added support, we don't have > to make it one step. Doing step by step can make reviewing easier. > >> + if (crash_low_size && reserve_crashkernel_low(crash_low_size)) { >> + memblock_phys_free(crash_base, crash_size); >> + return; >> + } >> + >> pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n", >> crash_base, crash_base + crash_size, crash_size >> 20); >> >> @@ -135,6 +183,9 @@ static void __init reserve_crashkernel(void) >> * map. Inform kmemleak so that it won't try to access it. >> */ >> kmemleak_ignore_phys(crash_base); >> + if (crashk_low_res.end) >> + kmemleak_ignore_phys(crashk_low_res.start); >> + >> crashk_res.start = crash_base; >> crashk_res.end = crash_base + crash_size - 1; >> insert_resource(&iomem_resource, &crashk_res); >> -- >> 2.25.1 >> > > . > -- Regards, Zhen Lei