Re: [PATCH V3] ia64/mm: fix a bad_page bug when crash kernel booting

Xishi Qiu
2013-02-16T01:55:44Z

On 2013/2/13 18:07, Matt Fleming wrote:

>> In efi_init() memory aligns in IA64_GRANULE_SIZE(16M). If set "crashkernel\x1024M-:600M"
>> and use sparse memory model, when crash kernel booting it changes [128M-728M] to [128M-720M].
>> But initrd memory is in [709M-727M], and virt_addr_valid() *can not* check the invalid pages
>> when freeing initrd memory. There are some pages missed at the end of the seciton.
>>
>> ChangeLog V3:
>> fixed vaddr mistake
>> ChangeLog V2:
>> add invalid pages check when freeing initrd memory
>>
>> Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
>> ---
>> arch/ia64/mm/init.c | 4 ++++
>> 1 files changed, 4 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
>> index 082e383..8a269f8 100644
>> --- a/arch/ia64/mm/init.c
>> +++ b/arch/ia64/mm/init.c
>> @@ -173,6 +173,7 @@ void __init
>> free_initrd_mem (unsigned long start, unsigned long end)
>> {
>> struct page *page;
>> + unsigned long pfn;
>> /*
>> * EFI uses 4KB pages while the kernel can use 4KB or bigger.
>> * Thus EFI and the kernel may have different page sizes. It is
>> @@ -213,6 +214,9 @@ free_initrd_mem (unsigned long start, unsigned long end)
>> for (; start < end; start += PAGE_SIZE) {
>> if (!virt_addr_valid(start))
>> continue;
>> + pfn = __pa(start) >> PAGE_SHIFT;
>> + if (pfn >= max_low_pfn)
>> + continue;
>> page = virt_to_page(start);
>> ClearPageReserved(page);
>> init_page_count(page);
>
> I would have presumed that fixing this bug would involve modifying the
> ia64-specific kexec code?
>
> Tony, Fenghua? Any thoughts?

Hi, I had the Spring Festival a few days ago. Please ignore the earlier
patch and consider the V3 one above.

Thanks,
Xishi Qiu