diff --git a/arch/powerpc/kernel/crash_dump.c b/arch/powerpc/kernel/crash_dump.c index e0debcca0bfa..a323c9b32ee1 100644 --- a/arch/powerpc/kernel/crash_dump.c +++ b/arch/powerpc/kernel/crash_dump.c @@ -86,6 +86,19 @@ static int __init parse_savemaxmem(char *p) } __setup("savemaxmem=", parse_savemaxmem); + +static size_t copy_oldmem_vaddr(void *vaddr, char *buf, size_t csize, + unsigned long offset, int userbuf) +{ + if (userbuf) { + if (copy_to_user((char __user *)buf, (vaddr + offset), csize)) + return -EFAULT; + } else + memcpy(buf, (vaddr + offset), csize); + + return csize; +} + /** * copy_oldmem_page - copy one page from "oldmem" * @pfn: page frame number to be copied @@ -107,16 +120,16 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, if (!csize) return 0; - vaddr = __ioremap(pfn << PAGE_SHIFT, PAGE_SIZE, 0); + csize = min(csize, PAGE_SIZE); - if (userbuf) { - if (copy_to_user((char __user *)buf, (vaddr + offset), csize)) { - iounmap(vaddr); - return -EFAULT; - } - } else - memcpy(buf, (vaddr + offset), csize); + if (pfn < max_pfn) { + vaddr = __va(pfn << PAGE_SHIFT); + csize = copy_oldmem_vaddr(vaddr, buf, csize, offset, userbuf); + } else { + vaddr = __ioremap(pfn << PAGE_SHIFT, PAGE_SIZE, 0); + csize = copy_oldmem_vaddr(vaddr, buf, csize, offset, userbuf); + iounmap(vaddr); + } - iounmap(vaddr); return csize; }