crash_dump: export is_kdump_kernel to modules, consolidate elfcorehdr_addr, setup_elf...

The Xen PV drivers in a crashed HVM guest can not connect to the dom0
backend drivers because both frontend and backend drivers are still in
connected state.  To run the connection reset function only in case of a
crashdump, the is_kdump_kernel() function needs to be available for the PV
driver modules.

Consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn into
kernel/crash_dump.c Also export elfcorehdr_addr to make is_kdump_kernel()
usable for modules.

Leave 'elfcorehdr' as early_param().  This changes powerpc from __setup()
to early_param().  It adds an address range check from x86 also on ia64
and powerpc.

[akpm@linux-foundation.org: additional #includes]
[akpm@linux-foundation.org: remove elfcorehdr_addr export]
[akpm@linux-foundation.org: fix for Tejun's mm/nobootmem.c changes]
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/arm/kernel/crash_dump.c b/arch/arm/kernel/crash_dump.c
index cd3b853a8a6dd9347ac02818164b81e3436a4040..90c50d4b43f74089b8a7eae08753c41ec00b4461 100644 (file)
--- a/arch/arm/kernel/crash_dump.c
+++ b/arch/arm/kernel/crash_dump.c
@@ -18,9 +18,6 @@
 #include <linux/uaccess.h>
 #include <linux/io.h>
 
-/* stores the physical address of elf header of crash image */
-unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
-
 /**
  * copy_oldmem_page() - copy one page from old kernel memory
  * @pfn: page frame number to be copied

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index d1da92174277b1fefe4f4a15529d5694b82216c3..c36c1a4250f3e867e9114c3628fb4375212a09f4 100644 (file)
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -788,30 +788,6 @@ static void __init reserve_crashkernel(void)
 static inline void reserve_crashkernel(void) {}
 #endif /* CONFIG_KEXEC */
 
-/*
- * Note: elfcorehdr_addr is not just limited to vmcore. It is also used by
- * is_kdump_kernel() to determine if we are booting after a panic. Hence
- * ifdef it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE.
- */
-
-#ifdef CONFIG_CRASH_DUMP
-/*
- * elfcorehdr= specifies the location of elf core header stored by the crashed
- * kernel. This option will be passed by kexec loader to the capture kernel.
- */
-static int __init setup_elfcorehdr(char *arg)
-{
-       char *end;
-
-       if (!arg)
-               return -EINVAL;
-
-       elfcorehdr_addr = memparse(arg, &end);
-       return end > arg ? 0 : -EINVAL;
-}
-early_param("elfcorehdr", setup_elfcorehdr);
-#endif /* CONFIG_CRASH_DUMP */
-
 static void __init squash_mem_tags(struct tag *tag)
 {
        for (; tag->hdr.size; tag = tag_next(tag))

diff --git a/arch/ia64/kernel/crash_dump.c b/arch/ia64/kernel/crash_dump.c
index 23e91290e41faf3151bbb93a7bfdde76553ecb3a..c8c9298666fb65cefdf1b5991b7dafa3ad8238dc 100644 (file)
--- a/arch/ia64/kernel/crash_dump.c
+++ b/arch/ia64/kernel/crash_dump.c
@@ -13,9 +13,6 @@
 #include <asm/page.h>
 #include <asm/uaccess.h>
 
-/* Stores the physical address of elf header of crash image. */
-unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
-
 /**
  * copy_oldmem_page - copy one page from "oldmem"
  * @pfn: page frame number to be copied

diff --git a/arch/ia64/kernel/efi.c b/arch/ia64/kernel/efi.c
index a0f001928502b6c1b8e692e36095df36e6b7f3b5..6fc03aff046c6a133a79d1305aa7b163fd310b70 100644 (file)
--- a/arch/ia64/kernel/efi.c
+++ b/arch/ia64/kernel/efi.c
@@ -23,6 +23,7 @@
  */
 #include <linux/module.h>
 #include <linux/bootmem.h>
+#include <linux/crash_dump.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/types.h>

diff --git a/arch/ia64/kernel/setup.c b/arch/ia64/kernel/setup.c
index 911cf974970008c6e01a92c36c2d1233ece62f8a..5e2c72498c516322d14b293b81b4365593bff1d1 100644 (file)
--- a/arch/ia64/kernel/setup.c
+++ b/arch/ia64/kernel/setup.c
@@ -479,25 +479,7 @@ static __init int setup_nomca(char *s)
 }
 early_param("nomca", setup_nomca);
 
-/*
- * Note: elfcorehdr_addr is not just limited to vmcore. It is also used by
- * is_kdump_kernel() to determine if we are booting after a panic. Hence
- * ifdef it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE.
- */
 #ifdef CONFIG_CRASH_DUMP
-/* elfcorehdr= specifies the location of elf core header
- * stored by the crashed kernel.
- */
-static int __init parse_elfcorehdr(char *arg)
-{
-       if (!arg)
-               return -EINVAL;
-
-        elfcorehdr_addr = memparse(arg, &arg);
-       return 0;
-}
-early_param("elfcorehdr", parse_elfcorehdr);
-
 int __init reserve_elfcorehdr(u64 *start, u64 *end)
 {
        u64 length;

diff --git a/arch/powerpc/kernel/crash_dump.c b/arch/powerpc/kernel/crash_dump.c
index 0a2af50243cb04f060e23ba250ea888be41700a1..424afb6b8fbaef07f9db351eb4429783b9baa83c 100644 (file)
--- a/arch/powerpc/kernel/crash_dump.c
+++ b/arch/powerpc/kernel/crash_dump.c
@@ -28,9 +28,6 @@
 #define DBG(fmt...)
 #endif
 
-/* Stores the physical address of elf header of crash image. */
-unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
-
 #ifndef CONFIG_RELOCATABLE
 void __init reserve_kdump_trampoline(void)
 {
@@ -72,20 +69,6 @@ void __init setup_kdump_trampoline(void)
 }
 #endif /* CONFIG_RELOCATABLE */
 
-/*
- * Note: elfcorehdr_addr is not just limited to vmcore. It is also used by
- * is_kdump_kernel() to determine if we are booting after a panic. Hence
- * ifdef it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE.
- */
-static int __init parse_elfcorehdr(char *p)
-{
-       if (p)
-               elfcorehdr_addr = memparse(p, &p);
-
-       return 1;
-}
-__setup("elfcorehdr=", parse_elfcorehdr);
-
 static int __init parse_savemaxmem(char *p)
 {
        if (p)

diff --git a/arch/sh/kernel/crash_dump.c b/arch/sh/kernel/crash_dump.c
index 37c97d444576133c9d2dc186aafc555bc57296ce..569e7b171c01656e646001cc88acb7ec0cc91328 100644 (file)
--- a/arch/sh/kernel/crash_dump.c
+++ b/arch/sh/kernel/crash_dump.c
@@ -9,28 +9,6 @@
 #include <linux/io.h>
 #include <asm/uaccess.h>
 
-/* Stores the physical address of elf header of crash image. */
-unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
-
-/*
- * Note: elfcorehdr_addr is not just limited to vmcore. It is also used by
- * is_kdump_kernel() to determine if we are booting after a panic. Hence
- * ifdef it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE.
- *
- * elfcorehdr= specifies the location of elf core header
- * stored by the crashed kernel.
- */
-static int __init parse_elfcorehdr(char *arg)
-{
-       if (!arg)
-               return -EINVAL;
-
-       elfcorehdr_addr = memparse(arg, &arg);
-
-       return 0;
-}
-early_param("elfcorehdr", parse_elfcorehdr);
-
 /**
  * copy_oldmem_page - copy one page from "oldmem"
  * @pfn: page frame number to be copied

diff --git a/arch/x86/kernel/crash_dump_32.c b/arch/x86/kernel/crash_dump_32.c
index d5cd13945d5a48a30cc0c61c26824aa2dad38b5b..642f75a68cd56653896dda18d2f26c3be9b22fe0 100644 (file)
--- a/arch/x86/kernel/crash_dump_32.c
+++ b/arch/x86/kernel/crash_dump_32.c
@@ -14,9 +14,6 @@
 
 static void *kdump_buf_page;
 
-/* Stores the physical address of elf header of crash image. */
-unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
-
 static inline bool is_crashed_pfn_valid(unsigned long pfn)
 {
 #ifndef CONFIG_X86_PAE

diff --git a/arch/x86/kernel/crash_dump_64.c b/arch/x86/kernel/crash_dump_64.c
index 994828899e098350d12ca73217235af843b0d497..afa64adb75eeb2bf830fbef1ef5a66960b14663e 100644 (file)
--- a/arch/x86/kernel/crash_dump_64.c
+++ b/arch/x86/kernel/crash_dump_64.c
@@ -10,9 +10,6 @@
 #include <linux/uaccess.h>
 #include <linux/io.h>
 
-/* Stores the physical address of elf header of crash image. */
-unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
-
 /**
  * copy_oldmem_page - copy one page from "oldmem"
  * @pfn: page frame number to be copied

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index cdf5bfd9d4d50d8eb2503fd15c38b7d013e90f4a..3e2ef842531649de082d64298c6cb1044446c1bf 100644 (file)
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -11,6 +11,7 @@
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/init.h>
+#include <linux/crash_dump.h>
 #include <linux/bootmem.h>
 #include <linux/pfn.h>
 #include <linux/suspend.h>

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 32bd87cbf982c0eb1d733d85e7d4bd1e6da77506..5a0484a95ad6b99ad1824058efdcb238170a9f93 100644 (file)
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -619,28 +619,6 @@ void __init reserve_standard_io_resources(void)
 
 }
 
-/*
- * Note: elfcorehdr_addr is not just limited to vmcore. It is also used by
- * is_kdump_kernel() to determine if we are booting after a panic. Hence
- * ifdef it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE.
- */
-
-#ifdef CONFIG_CRASH_DUMP
-/* elfcorehdr= specifies the location of elf core header
- * stored by the crashed kernel. This option will be passed
- * by kexec loader to the capture kernel.
- */
-static int __init setup_elfcorehdr(char *arg)
-{
-       char *end;
-       if (!arg)
-               return -EINVAL;
-       elfcorehdr_addr = memparse(arg, &end);
-       return end > arg ? 0 : -EINVAL;
-}
-early_param("elfcorehdr", setup_elfcorehdr);
-#endif
-
 static __init void reserve_ibft_region(void)
 {
        unsigned long addr, size = 0;

diff --git a/include/linux/bootmem.h b/include/linux/bootmem.h
index 499dfe982a0e8a21066e815daa400ac8b57ec5b4..b8613e806aa9c0b410b119519bc7044e44889570 100644 (file)
--- a/include/linux/bootmem.h
+++ b/include/linux/bootmem.h
@@ -19,10 +19,6 @@ extern unsigned long min_low_pfn;
  */
 extern unsigned long max_pfn;
 
-#ifdef CONFIG_CRASH_DUMP
-extern unsigned long saved_max_pfn;
-#endif
-
 #ifndef CONFIG_NO_BOOTMEM
 /*
  * node_bootmem_map is a map pointer - the bits represent all physical 

diff --git a/kernel/Makefile b/kernel/Makefile
index 353d3fe8ba339554655a0b61808a9d385dc55144..85cbfb31e73e97b2e2548cba6837a98c39cbaf2b 100644 (file)
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -107,6 +107,7 @@ obj-$(CONFIG_PERF_EVENTS) += perf_event.o
 obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
 obj-$(CONFIG_USER_RETURN_NOTIFIER) += user-return-notifier.o
 obj-$(CONFIG_PADATA) += padata.o
+obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
 
 ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y)
 # According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is

diff --git a/kernel/crash_dump.c b/kernel/crash_dump.c
new file mode 100644 (file)
index 0000000..5f85690
--- /dev/null
+++ b/kernel/crash_dump.c
@@ -0,0 +1,34 @@
+#include <linux/kernel.h>
+#include <linux/crash_dump.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/module.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
+ * is_kdump_kernel() to determine if we are booting after a panic. Hence put
+ * it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE.
+ */
+unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
+
+/*
+ * elfcorehdr= specifies the location of elf core header stored by the crashed
+ * kernel. This option will be passed by kexec loader to the capture kernel.
+ */
+static int __init setup_elfcorehdr(char *arg)
+{
+       char *end;
+       if (!arg)
+               return -EINVAL;
+       elfcorehdr_addr = memparse(arg, &end);
+       return end > arg ? 0 : -EINVAL;
+}
+early_param("elfcorehdr", setup_elfcorehdr);

diff --git a/mm/bootmem.c b/mm/bootmem.c
index 07aeb89e396ea140dbd7a28640aacb8fa2707b9a..01d5a4b3dd0c1dd857f05f474ce096a9a2938001 100644 (file)
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -34,14 +34,6 @@ unsigned long max_low_pfn;
 unsigned long min_low_pfn;
 unsigned long max_pfn;
 
-#ifdef CONFIG_CRASH_DUMP
-/*
- * 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;
-#endif
-
 bootmem_data_t bootmem_node_data[MAX_NUMNODES] __initdata;
 
 static struct list_head bdata_list __initdata = LIST_HEAD_INIT(bdata_list);

diff --git a/mm/nobootmem.c b/mm/nobootmem.c
index e2bdb07079cee8d67b7e1eb771fec6d509045145..e99f6cd1da1fccbb1756782c2218a75623b61b2f 100644 (file)
--- a/mm/nobootmem.c
+++ b/mm/nobootmem.c
@@ -32,14 +32,6 @@ unsigned long max_low_pfn;
 unsigned long min_low_pfn;
 unsigned long max_pfn;
 
-#ifdef CONFIG_CRASH_DUMP
-/*
- * 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;
-#endif
-
 static void * __init __alloc_memory_core_early(int nid, u64 size, u64 align,
                                        u64 goal, u64 limit)
 {