1 files changed, 32 insertions, 0 deletions

diff --git a/arch/i386/kernel/setup.c b/arch/i386/kernel/setup.c
index 6337157f5df3..d88ebdfa6ccd 100644
--- a/arch/i386/kernel/setup.c
+++ b/arch/i386/kernel/setup.c
@@ -43,7 +43,10 @@
 #include <linux/init.h>
 #include <linux/edd.h>
 #include <linux/nodemask.h>
+#include <linux/kexec.h>
+
 #include <video/edid.h>
+
 #include <asm/apic.h>
 #include <asm/e820.h>
 #include <asm/mpspec.h>
@@ -846,6 +849,27 @@ static void __init parse_cmdline_early (char ** cmdline_p)
                         lapic_disable();
 #endif /* CONFIG_X86_LOCAL_APIC */
 
+#ifdef CONFIG_KEXEC
+                /* crashkernel=size@addr specifies the location to reserve for
+                 * a crash kernel.  By reserving this memory we guarantee
+                 * that linux never set's it up as a DMA target.
+                 * Useful for holding code to do something appropriate
+                 * after a kernel panic.
+                 */
+                else if (!memcmp(from, "crashkernel=", 12)) {
+                        unsigned long size, base;
+                        size = memparse(from+12, &from);
+                        if (*from == '@') {
+                                base = memparse(from+1, &from);
+                                /* FIXME: Do I want a sanity check
+                                 * to validate the memory range?
+                                 */
+                                crashk_res.start = base;
+                                crashk_res.end   = base + size - 1;
+                        }
+                }
+#endif
+
                 /*
                  * highmem=size forces highmem to be exactly 'size' bytes.
                  * This works even on boxes that have no highmem otherwise.
@@ -1181,6 +1205,11 @@ void __init setup_bootmem_allocator(void)
                 }
         }
 #endif
+#ifdef CONFIG_KEXEC
+        if (crashk_res.start != crashk_res.end)
+                reserve_bootmem(crashk_res.start,
+                        crashk_res.end - crashk_res.start + 1);
+#endif
 }
 
 /*
@@ -1234,6 +1263,9 @@ legacy_init_iomem_resources(struct resource *code_resource, struct resource *dat
                          */
                         request_resource(res, code_resource);
                         request_resource(res, data_resource);
+#ifdef CONFIG_KEXEC
+                        request_resource(res, &crashk_res);
+#endif
                 }
         }
 }