crash_dump: Remove no longer used saved_max_pfn
saved_max_pfn was originally introduced in commit
92aa63a5a1bf ("[PATCH] kdump: Retrieve saved max pfn")
It used to make sure that the user does not try to read the physical memory
beyond saved_max_pfn. But since commit
921d58c0e699 ("vmcore: remove saved_max_pfn check")
it's no longer used for the check. This variable doesn't have any users
anymore so just remove it.
[ bp: Drop the Calgary IOMMU reference from the commit message. ]
Signed-off-by: Kairui Song <kasong@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Link: https://lkml.kernel.org/r/20200330181544.1595733-1-kasong@redhat.com
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index c5399e8..4d13c57 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -910,14 +910,6 @@ static int __init parse_memmap_one(char *p)
return -EINVAL;
if (!strncmp(p, "exactmap", 8)) {
-#ifdef CONFIG_CRASH_DUMP
- /*
- * If we are doing a crash dump, we still need to know
- * the real memory size before the original memory map is
- * reset.
- */
- saved_max_pfn = e820__end_of_ram_pfn();
-#endif
e820_table->nr_entries = 0;
userdef = 1;
return 0;
diff --git a/include/linux/crash_dump.h b/include/linux/crash_dump.h
index 4664fc1..bc15628 100644
--- a/include/linux/crash_dump.h
+++ b/include/linux/crash_dump.h
@@ -97,8 +97,6 @@ extern void unregister_oldmem_pfn_is_ram(void);
static inline bool is_kdump_kernel(void) { return 0; }
#endif /* CONFIG_CRASH_DUMP */
-extern unsigned long saved_max_pfn;
-
/* Device Dump information to be filled by drivers */
struct vmcoredd_data {
char dump_name[VMCOREDD_MAX_NAME_BYTES]; /* Unique name of the dump */
diff --git a/kernel/crash_dump.c b/kernel/crash_dump.c
index 9c23ae0..92da322 100644
--- a/kernel/crash_dump.c
+++ b/kernel/crash_dump.c
@@ -6,12 +6,6 @@
#include <linux/export.h>
/*
- * If we have booted due to a crash, max_pfn will be a very low value. We need
- * to know the amount of memory that the previous kernel used.
- */
-unsigned long saved_max_pfn;
-
-/*
* stores the physical address of elf header of crash image
*
* Note: elfcorehdr_addr is not just limited to vmcore. It is also used by