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Diffstat (limited to 'arch/powerpc/kernel/crash_dump.c')
-rw-r--r--arch/powerpc/kernel/crash_dump.c38
1 files changed, 27 insertions, 11 deletions
diff --git a/arch/powerpc/kernel/crash_dump.c b/arch/powerpc/kernel/crash_dump.c
index 9ee3c5278db..a323c9b32ee 100644
--- a/arch/powerpc/kernel/crash_dump.c
+++ b/arch/powerpc/kernel/crash_dump.c
@@ -14,6 +14,7 @@
#include <linux/crash_dump.h>
#include <linux/bootmem.h>
#include <linux/lmb.h>
+#include <asm/code-patching.h>
#include <asm/kdump.h>
#include <asm/prom.h>
#include <asm/firmware.h>
@@ -33,6 +34,8 @@ void __init reserve_kdump_trampoline(void)
static void __init create_trampoline(unsigned long addr)
{
+ unsigned int *p = (unsigned int *)addr;
+
/* The maximum range of a single instruction branch, is the current
* instruction's address + (32 MB - 4) bytes. For the trampoline we
* need to branch to current address + 32 MB. So we insert a nop at
@@ -41,8 +44,8 @@ static void __init create_trampoline(unsigned long addr)
* branch to "addr" we jump to ("addr" + 32 MB). Although it requires
* two instructions it doesn't require any registers.
*/
- create_instruction(addr, 0x60000000); /* nop */
- create_branch(addr + 4, addr + PHYSICAL_START, 0);
+ patch_instruction(p, PPC_NOP_INSTR);
+ patch_branch(++p, addr + PHYSICAL_START, 0);
}
void __init setup_kdump_trampoline(void)
@@ -83,6 +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
@@ -104,16 +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;
}