sparc64: crash kernel may only use reserved memory

In order to preserve the memory state of the original kernel, the
crash kernel may only use the memory reserved for it.

kexec-tools passes the reserved memory through the HdrS structure.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>

diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index 1b5178ef949ef5e2ae4bb18828b88d076b54634b..834bbe981e0cb0c39b473da3ca6a25b8734e29b0 100644 (file)
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -1563,7 +1563,8 @@ static unsigned long __init bootmem_init(unsigned long phys_base)
        unsigned long end_pfn;
 
        end_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
-       max_pfn = max_low_pfn = end_pfn;
+       end_pfn = max(end_pfn, max_pfn);
+       max_low_pfn = end_pfn;
        min_low_pfn = (phys_base >> PAGE_SHIFT);
 
        if (bootmem_init_numa() < 0)
@@ -2232,7 +2233,7 @@ static void __init reduce_memory(phys_addr_t limit_ram)
 
 void __init paging_init(void)
 {
-       unsigned long end_pfn, shift, phys_base;
+       unsigned long end_pfn, shift, phys_base, phys_end;
        unsigned long real_end, i;
        int node;
 
@@ -2319,11 +2320,28 @@ void __init paging_init(void)
        read_obp_memory("available", &pavail[0], &pavail_ents);
        read_obp_memory("available", &pavail[0], &pavail_ents);
 
+#ifdef CONFIG_KEXEC
+       /* Sanity check */
+       if (sparc_crash_base && !sparc_crash_size) {
+               printk(KERN_WARNING
+                      "sparc_crash_base defined, but not sparc_crash_size\n");
+               sparc_crash_base = 0;
+       }
+#endif
+
        phys_base = 0xffffffffffffffffUL;
+       phys_end = 0;
        for (i = 0; i < pavail_ents; i++) {
                phys_base = min(phys_base, pavail[i].phys_addr);
-               memblock_add(pavail[i].phys_addr, pavail[i].reg_size);
+               phys_end = max(phys_end,
+                              pavail[i].phys_addr + pavail[i].reg_size);
+               if (!sparc_crash_base)
+                       memblock_add(pavail[i].phys_addr, pavail[i].reg_size);
        }
+       max_pfn = phys_end >> PAGE_SHIFT;
+
+       if (sparc_crash_base)
+               memblock_add(sparc_crash_base, sparc_crash_size);
 
        memblock_reserve(kern_base, kern_size);