Messages in this thread | | | Date | Sat, 10 Mar 2012 12:32:28 +0800 | From | Dave Young <> | Subject | Re: [PATCH] kdump x86: fix total mem size calculation for reservation |
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On 03/10/2012 11:27 AM, Cong Wang wrote:
> On 03/09/2012 04:30 PM, Dave Young wrote: >> crashkernel reservation need know the total memory size. Current >> get_total_mem >> simply use max_pfn - min_low_pfn. It is wrong because it will including >> memory holes in the middle. >> >> Especially for kvm guest with memory> 0xe0000000, there's below in >> qemu code: >> qemu split memory as below: >> if (ram_size>= 0xe0000000 ) { >> above_4g_mem_size = ram_size - 0xe0000000; >> below_4g_mem_size = 0xe0000000; >> } else { >> below_4g_mem_size = ram_size; >> } >> So for 4G mem guest, seabios will insert a 512M usable region beyond >> of 4G. >> Thus in above case max_pfn - min_low_pfn will be more than original >> memsize. >> >> Fixing this issue by using memblock_phys_mem_size() to get the total >> memsize. >> > > Makes sense for me! > >> -static inline unsigned long long get_total_mem(void) >> -{ >> - unsigned long long total; >> - >> - total = max_pfn - min_low_pfn; >> - printk("hidave: memsize=%llu\n", memblock_phys_mem_size()); > > This debugging line does not exist... so this patch can't be applied.
Yes, good catch, will remove the line and resend.
-- Thanks Dave
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